Search Results: "p2"

30 December 2022

Chris Lamb: Favourite books of 2022: Non-fiction

In my three most recent posts, I went over the memoirs and biographies, classics and fiction books that I enjoyed the most in 2022. But in the last of my book-related posts for 2022, I'll be going over my favourite works of non-fiction. Books that just missed the cut here include Adam Hochschild's King Leopold's Ghost (1998) on the role of Leopold II of Belgium in the Congo Free State, Johann Hari's Stolen Focus (2022) (a personal memoir on relating to how technology is increasingly fragmenting our attention), Amia Srinivasan's The Right to Sex (2021) (a misleadingly named set of philosophic essays on feminism), Dana Heller et al.'s The Selling of 9/11: How a National Tragedy Became a Commodity (2005), John Berger's mindbending Ways of Seeing (1972) and Louise Richardson's What Terrorists Want (2006).

The Great War and Modern Memory (1975)
Wartime: Understanding and Behavior in the Second World War (1989) Paul Fussell Rather than describe the battles, weapons, geopolitics or big personalities of the two World Wars, Paul Fussell's The Great War and Modern Memory & Wartime are focused instead on how the two wars have been remembered by their everyday participants. Drawing on the memoirs and memories of soldiers and civilians along with a brief comparison with the actual events that shaped them, Fussell's two books are a compassionate, insightful and moving piece of analysis. Fussell primarily sets himself against the admixture of nostalgia and trauma that obscures the origins and unimaginable experience of participating in these wars; two wars that were, in his view, a "perceptual and rhetorical scandal from which total recovery is unlikely." He takes particular aim at the dishonesty of hindsight:
For the past fifty years, the Allied war has been sanitised and romanticised almost beyond recognition by the sentimental, the loony patriotic, the ignorant and the bloodthirsty. I have tried to balance the scales. [And] in unbombed America especially, the meaning of the war [seems] inaccessible.
The author does not engage in any of the customary rose-tinted view of war, yet he remains understanding and compassionate towards those who try to locate a reason within what was quite often senseless barbarism. If anything, his despondency and pessimism about the Second World War (the war that Fussell himself fought in) shines through quite acutely, and this is especially the case in what he chooses to quote from others:
"It was common [ ] throughout the [Okinawa] campaign for replacements to get hit before we even knew their names. They came up confused, frightened, and hopeful, got wounded or killed, and went right back to the rear on the route by which they had come, shocked, bleeding, or stiff. They were forlorn figures coming up to the meat grinder and going right back out of it like homeless waifs, unknown and faceless to us, like unread books on a shelf."
It would take a rather heartless reader to fail to be sobered by this final simile, and an even colder one to view Fussell's citation of such an emotive anecdote to be manipulative. Still, stories and cruel ironies like this one infuse this often-angry book, but it is not without astute and shrewd analysis as well, especially on the many qualitative differences between the two conflicts that simply cannot be captured by facts and figures alone. For example:
A measure of the psychological distance of the Second [World] War from the First is the rarity, in 1914 1918, of drinking and drunkenness poems.
Indeed so. In fact, what makes Fussell's project so compelling and perhaps even unique is that he uses these non-quantitive measures to try and take stock of what happened. After all, this was a war conducted by humans, not the abstract school of statistics. And what is the value of a list of armaments destroyed by such-and-such a regiment when compared with truly consequential insights into both how the war affected, say, the psychology of postwar literature ("Prolonged trench warfare, whether enacted or remembered, fosters paranoid melodrama, which I take to be a primary mode in modern writing."), the specific words adopted by combatants ("It is a truism of military propaganda that monosyllabic enemies are easier to despise than others") as well as the very grammar of interaction:
The Field Service Post Card [in WW1] has the honour of being the first widespread exemplary of that kind of document which uniquely characterises the modern world: the "Form". [And] as the first widely known example of dehumanised, automated communication, the post card popularised a mode of rhetoric indispensable to the conduct of later wars fought by great faceless conscripted armies.
And this wouldn't be a book review without argument-ending observations that:
Indicative of the German wartime conception [of victory] would be Hitler and Speer's elaborate plans for the ultimate reconstruction of Berlin, which made no provision for a library.
Our myths about the two world wars possess an undisputed power, in part because they contain an essential truth the atrocities committed by Germany and its allies were not merely extreme or revolting, but their full dimensions (embodied in the Holocaust and the Holodomor) remain essentially inaccessible within our current ideological framework. Yet the two wars are better understood as an abyss in which we were all dragged into the depths of moral depravity, rather than a battle pitched by the forces of light against the forces of darkness. Fussell is one of the few observers that can truly accept and understand this truth and is still able to speak to us cogently on the topic from the vantage point of experience. The Second World War which looms so large in our contemporary understanding of the modern world (see below) may have been necessary and unavoidable, but Fussell convinces his reader that it was morally complicated "beyond the power of any literary or philosophic analysis to suggest," and that the only way to maintain a na ve belief in the myth that these wars were a Manichaean fight between good and evil is to overlook reality. There are many texts on the two World Wars that can either stir the intellect or move the emotions, but Fussell's two books do both. A uniquely perceptive and intelligent commentary; outstanding.

Longitude (1995) Dava Sobel Since Man first decided to sail the oceans, knowing one's location has always been critical. Yet doing so reliably used to be a serious problem if you didn't know where you were, you are far more likely to die and/or lose your valuable cargo. But whilst finding one's latitude (ie. your north south position) had effectively been solved by the beginning of the 17th century, finding one's (east west) longitude was far from trustworthy in comparison. This book first published in 1995 is therefore something of an anachronism. As in, we readily use the GPS facilities of our phones today without hesitation, so we find it difficult to imagine a reality in which knowing something fundamental like your own location is essentially unthinkable. It became clear in the 18th century, though, that in order to accurately determine one's longitude, what you actually needed was an accurate clock. In Longitude, therefore, we read of the remarkable story of John Harrison and his quest to create a timepiece that would not only keep time during a long sea voyage but would survive the rough ocean conditions as well. Self-educated and a carpenter by trade, Harrison made a number of important breakthroughs in keeping accurate time at sea, and Longitude describes his novel breakthroughs in a way that is both engaging and without talking down to the reader. Still, this book covers much more than that, including the development of accurate longitude going hand-in-hand with advancements in cartography as well as in scientific experiments to determine the speed of light: experiments that led to the formulation of quantum mechanics. It also outlines the work being done by Harrison's competitors. 'Competitors' is indeed the correct word here, as Parliament offered a huge prize to whoever could create such a device, and the ramifications of this tremendous financial incentive are an essential part of this story. For the most part, though, Longitude sticks to the story of Harrison and his evolving obsession with his creating the perfect timepiece. Indeed, one reason that Longitude is so resonant with readers is that many of the tropes of the archetypical 'English inventor' are embedded within Harrison himself. That is to say, here is a self-made man pushing against the establishment of the time, with his groundbreaking ideas being underappreciated in his life, or dishonestly purloined by his intellectual inferiors. At the level of allegory, then, I am minded to interpret this portrait of Harrison as a symbolic distillation of postwar Britain a nation acutely embarrassed by the loss of the Empire that is now repositioning itself as a resourceful but plucky underdog; a country that, with a combination of the brains of boffins and a healthy dose of charisma and PR, can still keep up with the big boys. (It is this same search for postimperial meaning I find in the fiction of John le Carr , and, far more famously, in the James Bond franchise.) All of this is left to the reader, of course, as what makes Longitute singularly compelling is its gentle manner and tone. Indeed, at times it was as if the doyenne of sci-fi Ursula K. LeGuin had a sideline in popular non-fiction. I realise it's a mark of critical distinction to downgrade the importance of popular science in favour of erudite academic texts, but Latitude is ample evidence that so-called 'pop' science need not be patronising or reductive at all.

Closed Chambers: The Rise, Fall, and Future of the Modern Supreme Court (1998) Edward Lazarus After the landmark decision by the U.S. Supreme Court in *Dobbs v. Jackson Women's Health Organization that ended the Constitutional right to abortion conferred by Roe v Wade, I prioritised a few books in the queue about the judicial branch of the United States. One of these books was Closed Chambers, which attempts to assay, according to its subtitle, "The Rise, Fall and Future of the Modern Supreme Court". This book is not merely simply a learned guide to the history and functioning of the Court (although it is completely creditable in this respect); it's actually an 'insider' view of the workings of the institution as Lazurus was a clerk for Justice Harry Blackmun during the October term of 1988. Lazarus has therefore combined his experience as a clerk and his personal reflections (along with a substantial body of subsequent research) in order to communicate the collapse in comity between the Justices. Part of this book is therefore a pure history of the Court, detailing its important nineteenth-century judgements (such as Dred Scott which ruled that the Constitution did not consider Blacks to be citizens; and Plessy v. Ferguson which failed to find protection in the Constitution against racial segregation laws), as well as many twentieth-century cases that touch on the rather technical principle of substantive due process. Other layers of Lazurus' book are explicitly opinionated, however, and they capture the author's assessment of the Court's actions in the past and present [1998] day. Given the role in which he served at the Court, particular attention is given by Lazarus to the function of its clerks. These are revealed as being far more than the mere amanuenses they were hitherto believed to be. Indeed, the book is potentially unique in its the claim that the clerks have played a pivotal role in the deliberations, machinations and eventual rulings of the Court. By implication, then, the clerks have plaedy a crucial role in the internal controversies that surround many of the high-profile Supreme Court decisions decisions that, to the outsider at least, are presented as disinterested interpretations of Constitution of the United States. This is of especial importance given that, to Lazarus, "for all the attention we now pay to it, the Court remains shrouded in confusion and misunderstanding." Throughout his book, Lazarus complicates the commonplace view that the Court is divided into two simple right vs. left political factions, and instead documents an ever-evolving series of loosely held but strongly felt series of cabals, quid pro quo exchanges, outright equivocation and pure personal prejudices. (The age and concomitant illnesses of the Justices also appears to have a not insignificant effect on the Court's rulings as well.) In other words, Closed Chambers is not a book that will be read in a typical civics class in America, and the only time the book resorts to the customary breathless rhetoric about the US federal government is in its opening chapter:
The Court itself, a Greek-style temple commanding the crest of Capitol Hill, loomed above them in the dim light of the storm. Set atop a broad marble plaza and thirty-six steps, the Court stands in splendid isolation appropriate to its place at the pinnacle of the national judiciary, one of the three independent and "coequal" branches of American government. Once dubbed the Ivory Tower by architecture critics, the Court has a Corinthian colonnade and massive twenty-foot-high bronze doors that guard the single most powerful judicial institution in the Western world. Lights still shone in several offices to the right of the Court's entrance, and [ ]
Et cetera, et cetera. But, of course, this encomium to the inherent 'nobility' of the Supreme Court is quickly revealed to be a narrative foil, as Lazarus soon razes this dangerously na ve conception to the ground:
[The] institution is [now] broken into unyielding factions that have largely given up on a meaningful exchange of their respective views or, for that matter, a meaningful explication or defense of their own views. It is of Justices who in many important cases resort to transparently deceitful and hypocritical arguments and factual distortions as they discard judicial philosophy and consistent interpretation in favor of bottom-line results. This is a Court so badly splintered, yet so intent on lawmaking, that shifting 5-4 majorities, or even mere pluralities, rewrite whole swaths of constitutional law on the authority of a single, often idiosyncratic vote. It is also a Court where Justices yield great and excessive power to immature, ideologically driven clerks, who in turn use that power to manipulate their bosses and the institution they ostensibly serve.
Lazurus does not put forward a single, overarching thesis, but in the final chapters, he does suggest a potential future for the Court:
In the short run, the cure for what ails the Court lies solely with the Justices. It is their duty, under the shield of life tenure, to recognize the pathologies affecting their work and to restore the vitality of American constitutionalism. Ultimately, though, the long-term health of the Court depends on our own resolve on whom [we] select to join that institution.
Back in 1998, Lazurus might have had room for this qualified optimism. But from the vantage point of 2022, it appears that the "resolve" of the United States citizenry was not muscular enough to meet his challenge. After all, Lazurus was writing before Bush v. Gore in 2000, which arrogated to the judicial branch the ability to decide a presidential election; the disillusionment of Barack Obama's failure to nominate a replacement for Scalia; and many other missteps in the Court as well. All of which have now been compounded by the Trump administration's appointment of three Republican-friendly justices to the Court, including hypocritically appointing Justice Barrett a mere 38 days before the 2020 election. And, of course, the leaking and ruling in Dobbs v. Jackson, the true extent of which has not been yet. Not of a bit of this is Lazarus' fault, of course, but the Court's recent decisions (as well as the liberal hagiographies of 'RBG') most perforce affect one's reading of the concluding chapters. The other slight defect of Closed Chambers is that, whilst it often implies the importance of the federal and state courts within the judiciary, it only briefly positions the Supreme Court's decisions in relation to what was happening in the House, Senate and White House at the time. This seems to be increasingly relevant as time goes on: after all, it seems fairly clear even to this Brit that relying on an activist Supreme Court to enact progressive laws must be interpreted as a failure of the legislative branch to overcome the perennial problems of the filibuster, culture wars and partisan bickering. Nevertheless, Lazarus' book is in equal parts ambitious, opinionated, scholarly and dare I admit it? wonderfully gossipy. By juxtaposing history, memoir, and analysis, Closed Chambers combines an exacting evaluation of the Court's decisions with a lively portrait of the intellectual and emotional intensity that has grown within the Supreme Court's pseudo-monastic environment all while it struggles with the most impactful legal issues of the day. This book is an excellent and well-written achievement that will likely never be repeated, and a must-read for anyone interested in this ever-increasingly important branch of the US government.

Crashed: How a Decade of Financial Crises Changed the World (2018)
Shutdown: How Covid Shook the World's Economy (2021) Adam Tooze The economic historian Adam Tooze has often been labelled as an unlikely celebrity, but in the fourteen years since the global financial crisis of 2008, a growing audience has been looking for answers about the various failures of the modern economy. Tooze, a professor of history at New York's Columbia University, has written much that is penetrative and thought-provoking on this topic, and as a result, he has generated something of a cult following amongst economists, historians and the online left. I actually read two Tooze books this year. The first, Crashed (2018), catalogues the scale of government intervention required to prop up global finance after the 2008 financial crisis, and it characterises the different ways that countries around the world failed to live up to the situation, such as doing far too little, or taking action far too late. The connections between the high-risk subprime loans, credit default swaps and the resulting liquidity crisis in the US in late 2008 is fairly well known today in part thanks to films such as Adam McKay's 2015 The Big Short and much improved economic literacy in media reportage. But Crashed makes the implicit claim that, whilst the specific and structural origins of the 2008 crisis are worth scrutinising in exacting detail, it is the reaction of states in the months and years after the crash that has been overlooked as a result. After all, this is a reaction that has not only shaped a new economic order, it has created one that does not fit any conventional idea about the way the world 'ought' to be run. Tooze connects the original American banking crisis to the (multiple) European debt crises with a larger crisis of liberalism. Indeed, Tooze somehow manages to cover all these topics and more, weaving in Trump, Brexit and Russia's 2014 annexation of Crimea, as well as the evolving role of China in the post-2008 economic order. Where Crashed focused on the constellation of consequences that followed the events of 2008, Shutdown is a clear and comprehensive account of the way the world responded to the economic impact of Covid-19. The figures are often jaw-dropping: soon after the disease spread around the world, 95% of the world's economies contracted simultaneously, and at one point, the global economy shrunk by approximately 20%. Tooze's keen and sobering analysis of what happened is made all the more remarkable by the fact that it came out whilst the pandemic was still unfolding. In fact, this leads quickly to one of the book's few flaws: by being published so quickly, Shutdown prematurely over-praises China's 'zero Covid' policy, and these remarks will make a reader today squirm in their chair. Still, despite the regularity of these references (after all, mentioning China is very useful when one is directly comparing economic figures in early 2021, for examples), these are actually minor blemishes on the book's overall thesis. That is to say, Crashed is not merely a retelling of what happened in such-and-such a country during the pandemic; it offers in effect a prediction about what might be coming next. Whilst the economic responses to Covid averted what could easily have been another Great Depression (and thus showed it had learned some lessons from 2008), it had only done so by truly discarding the economic rule book. The by-product of inverting this set of written and unwritten conventions that have governed the world for the past 50 years, this 'Washington consensus' if you well, has yet to be fully felt. Of course, there are many parallels between these two books by Tooze. Both the liquidity crisis outlined in Crashed and the economic response to Covid in Shutdown exposed the fact that one of the central tenets of the modern economy ie. that financial markets can be trusted to regulate themselves was entirely untrue, and likely was false from the very beginning. And whilst Adam Tooze does not offer a singular piercing insight (conveying a sense of rigorous mastery instead), he may as well be asking whether we're simply going to lurch along from one crisis to the next, relying on the technocrats in power to fix problems when everything blows up again. The answer may very well be yes.

Looking for the Good War: American Amnesia and the Violent Pursuit of Happiness (2021) Elizabeth D. Samet Elizabeth D. Samet's Looking for the Good War answers the following question what would be the result if you asked a professor of English to disentangle the complex mythology we have about WW2 in the context of the recent US exit of Afghanistan? Samet's book acts as a twenty-first-century update of a kind to Paul Fussell's two books (reviewed above), as well as a deeper meditation on the idea that each new war is seen through the lens of the previous one. Indeed, like The Great War and Modern Memory (1975) and Wartime (1989), Samet's book is a perceptive work of demystification, but whilst Fussell seems to have been inspired by his own traumatic war experience, Samet is not only informed by her teaching West Point military cadets but by the physical and ontological wars that have occurred during her own life as well. A more scholarly and dispassionate text is the result of Samet's relative distance from armed combat, but it doesn't mean Looking for the Good War lacks energy or inspiration. Samet shares John Adams' belief that no political project can entirely shed the innate corruptions of power and ambition and so it is crucial to analyse and re-analyse the role of WW2 in contemporary American life. She is surely correct that the Second World War has been universally elevated as a special, 'good' war. Even those with exceptionally giddy minds seem to treat WW2 as hallowed:
It is nevertheless telling that one of the few occasions to which Trump responded with any kind of restraint while he was in office was the 75th anniversary of D-Day in 2019.
What is the source of this restraint, and what has nurtured its growth in the eight decades since WW2 began? Samet posits several reasons for this, including the fact that almost all of the media about the Second World War is not only suffused with symbolism and nostalgia but, less obviously, it has been made by people who have no experience of the events that they depict. Take Stephen Ambrose, author of Steven Spielberg's Band of Brothers miniseries: "I was 10 years old when the war ended," Samet quotes of Ambrose. "I thought the returning veterans were giants who had saved the world from barbarism. I still think so. I remain a hero worshiper." If Looking for the Good War has a primary thesis, then, it is that childhood hero worship is no basis for a system of government, let alone a crusading foreign policy. There is a straight line (to quote this book's subtitle) from the "American Amnesia" that obscures the reality of war to the "Violent Pursuit of Happiness." Samet's book doesn't merely just provide a modern appendix to Fussell's two works, however, as it adds further layers and dimensions he overlooked. For example, Samet provides some excellent insight on the role of Western, gangster and superhero movies, and she is especially good when looking at noir films as a kind of kaleidoscopic response to the Second World War:
Noir is a world ruled by bad decisions but also by bad timing. Chance, which plays such a pivotal role in war, bleeds into this world, too.
Samet rightfully weaves the role of women into the narrative as well. Women in film noir are often celebrated as 'independent' and sassy, correctly reflecting their newly-found independence gained during WW2. But these 'liberated' roles are not exactly a ringing endorsement of this independence: the 'femme fatale' and the 'tart', etc., reflect a kind of conditional freedom permitted to women by a post-War culture which is still wedded to an outmoded honour culture. In effect, far from being novel and subversive, these roles for women actually underwrote the ambient cultural disapproval of women's presence in the workforce. Samet later connects this highly-conditional independence with the liberation of Afghan women, which:
is inarguably one of the more palatable outcomes of our invasion, and the protection of women's rights has been invoked on the right and the left as an argument for staying the course in Afghanistan. How easily consequence is becoming justification. How flattering it will be one day to reimagine it as original objective.
Samet has ensured her book has a predominantly US angle as well, for she ends her book with a chapter on the pseudohistorical Lost Cause of the Civil War. The legacy of the Civil War is still visible in the physical phenomena of Confederate statues, but it also exists in deep-rooted racial injustice that has been shrouded in euphemism and other psychological devices for over 150 years. Samet believes that a key part of what drives the American mythology about the Second World War is the way in which it subconsciously cleanses the horrors of brother-on-brother murder that were seen in the Civil War. This is a book that is not only of interest to historians of the Second World War; it is a work for anyone who wishes to understand almost any American historical event, social issue, politician or movie that has appeared since the end of WW2. That is for better or worse everyone on earth.

29 December 2022

Chris Lamb: Favourite books of 2022: Memoir/biography

In my two most recent posts, I listed the fiction and classic fiction I enjoyed the most in 2022. I'll leave my roundup of general non-fiction until tomorrow, but today I'll be going over my favourite memoirs and biographies, in no particular order. Books that just missed the cut here include Roisin Kiberd's The Disconnect: A Personal Journey Through the Internet (2019), Steve Richards' The Prime Ministers (2019) which reflects on UK leadership from Harold Wilson to Boris Johnson, Robert Graves Great War memoir Goodbye to All That (1929) and David Mikics's portrait of Stanley Kubrick called American Filmmaker.

Afropean: Notes from Black Europe (2019) Johny Pitts Johny Pitts is a photographer and writer who lives in the north of England who set out to explore "black Europe from the street up" those districts within European cities that, although they were once 'white spaces' in the past, they are now occupied by Black people. Unhappy with the framing of the Black experience back home in post-industrial Sheffield, Pitts decided to become a nomad and goes abroad to seek out the sense of belonging he cannot find in post-Brexit Britain, and Afropean details his journey through Paris, Brussels, Lisbon, Berlin, Stockholm and Moscow. However, Pitts isn't just avoiding the polarisation and structural racism embedded in contemporary British life. Rather, he is seeking a kind of super-national community that transcends the reductive and limiting nationalisms of all European countries, most of which have based their national story on a self-serving mix of nostalgia and postcolonial fairy tales. Indeed, the term 'Afropean' is the key to understanding the goal of this captivating memoir. Pitts writes at the beginning of this book that the word wasn't driven only as a response to the crude nativisms of Nigel Farage and Marine Le Pen, but that it:
encouraged me to think of myself as whole and unhyphenated. [ ] Here was a space where blackness was taking part in shaping European identity at large. It suggested the possibility of living in and with more than one idea: Africa and Europe, or, by extension, the Global South and the West, without being mixed-this, half-that or black-other. That being black in Europe didn t necessarily mean being an immigrant.
In search of this whole new theory of home, Pitts travels to the infamous banlieue of Clichy-sous-Bois just to the East of Paris, thence to Matong in Brussels, as well as a quick and abortive trip into Moscow and other parallel communities throughout the continent. In these disparate environs, Pitts strikes up countless conversations with regular folk in order to hear their quotidian stories of living, and ultimately to move away from the idea that Black history is defined exclusively by slavery. Indeed, to Pitts, the idea of race is one that ultimately restricts one's humanity; the concept "is often forced to embody and speak for certain ideas, despite the fact it can't ever hold in both hands the full spectrum of a human life and the cultural nuances it creates." It's difficult to do justice to the effectiveness of the conversations Pitts has throughout his travels, but his shrewd attention to demeanour, language, raiment and expression vividly brings alive the people he talks to. Of related interest to fellow Brits as well are the many astute observations and comparisons with Black and working-class British life. The tone shifts quite often throughout this book. There might be an amusing aside one minute, such as the portrait of an African American tourist in Paris to whom "the whole city was a film set, with even its homeless people appearing to him as something oddly picturesque." But the register abruptly changes when he visits Clichy-sous-Bois on an anniversary of important to the area, and an element of genuine danger is introduced when Johny briefly visits Moscow and barely gets out alive. What's especially remarkable about this book is there is a freshness to Pitt s treatment of many well-worn subjects. This can be seen in his account of Belgium under the reign of Leopold II, the history of Portuguese colonialism (actually mostly unknown to me), as well in the way Pitts' own attitude to contemporary anti-fascist movements changes throughout an Antifa march. This chapter was an especial delight, and not only because it underlined just how much of Johny's trip was an inner journey of an author willing have his mind changed. Although Johny travels alone throughout his journey, in the second half of the book, Pitts becomes increasingly accompanied by a number of Black intellectuals by the selective citing of Frantz Fanon and James Baldwin and Caryl Phillips. (Nevertheless, Jonny has also brought his camera for the journey as well, adding a personal touch to this already highly-intimate book.) I suspect that his increasing exercise of Black intellectual writing in the latter half of the book may be because Pitts' hopes about 'Afropean' existence ever becoming a reality are continually dashed and undercut. The unity among potential Afropeans appears more-and-more unrealisable as the narrative unfolds, the various reasons of which Johny explores both prosaically and poetically. Indeed, by the end of the book, it's unclear whether Johny has managed to find what he left the shores of England to find. But his mix of history, sociology and observation of other cultures right on my doorstep was something of a revelation to me.

Orwell's Roses (2021) Rebecca Solnit Orwell s Roses is an alternative journey through the life and afterlife of George Orwell, reimaging his life primarily through the lens of his attentiveness to nature. Yet this framing of the book as an 'alternative' history is only revisionist if we compare it to the usual view of Orwell as a bastion of 'free speech' and English 'common sense' the roses of the title of this book were very much planted by Orwell in his Hertfordshire garden in 1936, and his yearning of nature one was one of the many constants throughout his life. Indeed, Orwell wrote about wildlife and outdoor life whenever he could get away with it, taking pleasure in a blackbird's song and waxing nostalgically about the English countryside in his 1939 novel Coming Up for Air (reviewed yesterday).
By sheer chance, I actually visited this exact garden immediately to the publication of this book
Solnit has a particular ability to evince unexpected connections between Orwell and the things he was writing about: Joseph Stalin's obsession with forcing lemons to grow in ludicrously cold climates; Orwell s slave-owning ancestors in Jamaica; Jamaica Kincaid's critique of colonialism in the flower garden; and the exploitative rose industry in Colombia that supplies the American market. Solnit introduces all of these new correspondences in a voice that feels like a breath of fresh air after decades of stodgy Orwellania, and without lapsing into a kind of verbal soft-focus. Indeed, the book displays a marked indifference towards the usual (male-centric) Orwell fandom. Her book draws to a close with a rereading of the 'dystopian' Nineteen Eighty-Four that completes her touching portrait of a more optimistic and hopeful Orwell, as well as a reflection on beauty and a manifesto for experiencing joy as an act of resistance.

The Disaster Artist (2013) Greg Sestero & Tom Bissell For those not already in the know, The Room was a 2003 film by director-producer-writer-actor Tommy Wiseau, an inscrutable Polish immigr with an impenetrable background, an idiosyncratic choice of wardrobe and a mysterious large source of income. The film, which centres on a melodramatic love triangle, has since been described by several commentators and publications as one of the worst films ever made. Tommy's production completely bombed at the so-called 'box office' (the release was actually funded entirely by Wiseau personally), but the film slowly became a favourite at cult cinema screenings. Given Tommy's prominent and central role in the film, there was always an inherent cruelty involved in indulging in the spectacle of The Room the audience was laughing because the film was astonishingly bad, of course, but Wiseau infused his film with sincere earnestness that in a heartless twist of irony may be precisely why it is so terrible to begin with. Indeed, it should be stressed that The Room is not simply a 'bad' film, and therefore not worth paying any attention to: it is uncannily bad in a way that makes it eerily compelling to watch. It unintentionally subverts all the rules of filmmaking in a way that captivates the attention. Take this representative example:
This thirty-six-second scene showcases almost every problem in The Room: the acting, the lighting, the sound design, the pacing, the dialogue and that this unnecessary scene (which does not advance the plot) even exists in the first place. One problem that the above clip doesn't capture, however, is Tommy's vulnerable ego. (He would later make the potentially conflicting claims that The Room was both an ironic cult success and that he is okay with people interpreting it sincerely). Indeed, the filmmaker's central role as Johnny (along with his Willy-Wonka meets Dracula persona) doesn't strike viewers as yet another vanity project, it actually asks more questions than it answers. Why did Tommy even make this film? What is driving him psychologically? And why and how? is he so spellbinding? On the surface, then, 2013's The Disaster Artist is a book about the making of one the strangest films ever made, written by The Room's co-star Greg Sestero and journalist Tom Bissell. Naturally, you learn some jaw-dropping facts about the production and inspiration of the film, the seed of which was planted when Greg and Tommy went to see an early screening of The Talented Mr Ripley (1999). It turns out that Greg's character in The Room is based on Tommy's idiosyncratic misinterpretation of its plot, extending even to the character's name Mark who, in textbook Tommy style, was taken directly (or at least Tommy believed) from one of Ripley's movie stars: "Mark Damon" [sic]. Almost as absorbing as The Room itself, The Disaster Artist is partly a memoir about Thomas P. Wiseau and his cinematic masterpiece. But it could also be described as a biography about a dysfunctional male relationship and, almost certainly entirely unconsciously, a text about the limitations of hetronormativity. It is this latter element that struck me the most whilst reading this book: if you take a step back for a moment, there is something uniquely sad about Tommy's inability to connect with others, and then, when Wiseau poured his soul into his film people just laughed. Despite the stories about his atrocious behaviour both on and off the film set, there's something deeply tragic about the whole affair. Jean-Luc Godard, who passed away earlier this year, once observed that every fictional film is a documentary of its actors. The Disaster Artist shows that this well-worn aphorism doesn't begin to cover it.

28 December 2022

Chris Lamb: Favourite books of 2022: Classics

As a follow-up to yesterday's post detailing my favourite works of fiction from 2022, today I'll be listing my favourite fictional works that are typically filed under classics. Books that just missed the cut here include: E. M. Forster's A Room with a View (1908) and his later A Passage to India (1913), both gently nudged out by Forster's superb Howard's End (see below). Giuseppe Tomasi di Lampedusa's The Leopard (1958) also just missed out on a write-up here, but I can definitely recommend it to anyone interested in reading a modern Italian classic.

War and Peace (1867) Leo Tolstoy It's strange to think that there is almost no point in reviewing this novel: who hasn't heard of War and Peace? What more could possibly be said about it now? Still, when I was growing up, War and Peace was always the stereotypical example of the 'impossible book', and even start it was, at best, a pointless task, and an act of hubris at worst. And so there surely exists a parallel universe in which I never have and will never will read the book... Nevertheless, let us try to set the scene. Book nine of the novel opens as follows:
On the twelfth of June, 1812, the forces of Western Europe crossed the Russian frontier and war began; that is, an event took place opposed to human reason and to human nature. Millions of men perpetrated against one another such innumerable crimes, frauds, treacheries, thefts, forgeries, issues of false money, burglaries, incendiarisms and murders as in whole centuries are not recorded in the annals of all the law courts of the world, but which those who committed them did not at the time regard as being crimes. What produced this extraordinary occurrence? What were its causes? [ ] The more we try to explain such events in history reasonably, the more unreasonable and incomprehensible they become to us.
Set against the backdrop of the Napoleonic Wars and Napoleon's invasion of Russia, War and Peace follows the lives and fates of three aristocratic families: The Rostovs, The Bolkonskys and the Bezukhov's. These characters find themselves situated athwart (or against) history, and all this time, Napoleon is marching ever closer to Moscow. Still, Napoleon himself is essentially just a kind of wallpaper for a diverse set of personal stories touching on love, jealousy, hatred, retribution, naivety, nationalism, stupidity and much much more. As Elif Batuman wrote earlier this year, "the whole premise of the book was that you couldn t explain war without recourse to domesticity and interpersonal relations." The result is that Tolstoy has woven an incredibly intricate web that connects the war, noble families and the everyday Russian people to a degree that is surprising for a book started in 1865. Tolstoy's characters are probably timeless (especially the picaresque adventures and constantly changing thoughts Pierre Bezukhov), and the reader who has any social experience will immediately recognise characters' thoughts and actions. Some of this is at a 'micro' interpersonal level: for instance, take this example from the elegant party that opens the novel:
Each visitor performed the ceremony of greeting this old aunt whom not one of them knew, not one of them wanted to know, and not one of them cared about. The aunt spoke to each of them in the same words, about their health and her own and the health of Her Majesty, who, thank God, was better today. And each visitor, though politeness prevented his showing impatience, left the old woman with a sense of relief at having performed a vexatious duty and did not return to her the whole evening.
But then, some of the focus of the observations are at the 'macro' level of the entire continent. This section about cities that feel themselves in danger might suffice as an example:
At the approach of danger, there are always two voices that speak with equal power in the human soul: one very reasonably tells a man to consider the nature of the danger and the means of escaping it; the other, still more reasonably, says that it is too depressing and painful to think of the danger, since it is not in man s power to foresee everything and avert the general course of events, and it is therefore better to disregard what is painful till it comes and to think about what is pleasant. In solitude, a man generally listens to the first voice, but in society to the second.
And finally, in his lengthy epilogues, Tolstoy offers us a dissertation on the behaviour of large organisations, much of it through engagingly witty analogies. These epilogues actually turn out to be an oblique and sarcastic commentary on the idiocy of governments and the madness of war in general. Indeed, the thorough dismantling of the 'great man' theory of history is a common theme throughout the book:
During the whole of that period [of 1812], Napoleon, who seems to us to have been the leader of all these movements as the figurehead of a ship may seem to a savage to guide the vessel acted like a child who, holding a couple of strings inside a carriage, thinks he is driving it. [ ] Why do [we] all speak of a military genius ? Is a man a genius who can order bread to be brought up at the right time and say who is to go to the right and who to the left? It is only because military men are invested with pomp and power and crowds of sychophants flatter power, attributing to it qualities of genius it does not possess.
Unlike some other readers, I especially enjoyed these diversions into the accounting and workings of history, as well as our narrow-minded way of trying to 'explain' things in a singular way:
When an apple has ripened and falls, why does it fall? Because of its attraction to the earth, because its stalk withers, because it is dried by the sun, because it grows heavier, because the wind shakes it, or because the boy standing below wants to eat it? Nothing is the cause. All this is only the coincidence of conditions in which all vital organic and elemental events occur. And the botanist who finds that the apple falls because the cellular tissue decays and so forth is equally right with the child who stands under the tree and says the apple fell because he wanted to eat it and prayed for it.
Given all of these serious asides, I was also not expecting this book to be quite so funny. At the risk of boring the reader with citations, take this sarcastic remark about the ineptness of medicine men:
After his liberation, [Pierre] fell ill and was laid up for three months. He had what the doctors termed 'bilious fever.' But despite the fact that the doctors treated him, bled him and gave him medicines to drink he recovered.
There is actually a multitude of remarks that are not entirely complimentary towards Russian medical practice, but they are usually deployed with an eye to the human element involved rather than simply to the detriment of a doctor's reputation "How would the count have borne his dearly loved daughter s illness had he not known that it was costing him a thousand rubles?" Other elements of note include some stunning set literary pieces, such as when Prince Andrei encounters a gnarly oak tree under two different circumstances in his life, and when Nat sha's 'Russian' soul is awakened by the strains of a folk song on the balalaika. Still, despite all of these micro- and macro-level happenings, for a long time I felt that something else was going on in War and Peace. It was difficult to put into words precisely what it was until I came across this passage by E. M. Forster:
After one has read War and Peace for a bit, great chords begin to sound, and we cannot say exactly what struck them. They do not arise from the story [and] they do not come from the episodes nor yet from the characters. They come from the immense area of Russia, over which episodes and characters have been scattered, from the sum-total of bridges and frozen rivers, forests, roads, gardens and fields, which accumulate grandeur and sonority after we have passed them. Many novelists have the feeling for place, [but] very few have the sense of space, and the possession of it ranks high in Tolstoy s divine equipment. Space is the lord of War and Peace, not time.
'Space' indeed. Yes, potential readers should note the novel's great length, but the 365 chapters are actually remarkably short, so the sensation of reading it is not in the least overwhelming. And more importantly, once you become familiar with its large cast of characters, it is really not a difficult book to follow, especially when compared to the other Russian classics. My only regret is that it has taken me so long to read this magnificent novel and that I might find it hard to find time to re-read it within the next few years.

Coming Up for Air (1939) George Orwell It wouldn't be a roundup of mine without at least one entry from George Orwell, and, this year, that place is occupied by a book I hadn't haven't read in almost two decades Still, the George Bowling of Coming Up for Air is a middle-aged insurance salesman who lives in a distinctly average English suburban row house with his nuclear family. One day, after winning some money on a bet, he goes back to the village where he grew up in order to fish in a pool he remembers from thirty years before. Less important than the plot, however, is both the well-observed remarks and scathing criticisms that Bowling has of the town he has returned to, combined with an ominous sense of foreboding before the Second World War breaks out. At several times throughout the book, George's placid thoughts about his beloved carp pool are replaced by racing, anxious thoughts that overwhelm his inner peace:
War is coming. In 1941, they say. And there'll be plenty of broken crockery, and little houses ripped open like packing-cases, and the guts of the chartered accountant's clerk plastered over the piano that he's buying on the never-never. But what does that kind of thing matter, anyway? I'll tell you what my stay in Lower Binfield had taught me, and it was this. IT'S ALL GOING TO HAPPEN. All the things you've got at the back of your mind, the things you're terrified of, the things that you tell yourself are just a nightmare or only happen in foreign countries. The bombs, the food-queues, the rubber truncheons, the barbed wire, the coloured shirts, the slogans, the enormous faces, the machine-guns squirting out of bedroom windows. It's all going to happen. I know it - at any rate, I knew it then. There's no escape. Fight against it if you like, or look the other way and pretend not to notice, or grab your spanner and rush out to do a bit of face-smashing along with the others. But there's no way out. It's just something that's got to happen.
Already we can hear psychological madness that underpinned the Second World War. Indeed, there is no great story in Coming Up For Air, no wonderfully empathetic characters and no revelations or catharsis, so it is impressive that I was held by the descriptions, observations and nostalgic remembrances about life in modern Lower Binfield, its residents, and how it has changed over the years. It turns out, of course, that George's beloved pool has been filled in with rubbish, and the village has been perverted by modernity beyond recognition. And to cap it off, the principal event of George's holiday in Lower Binfield is an accidental bombing by the British Royal Air Force. Orwell is always good at descriptions of awful food, and this book is no exception:
The frankfurter had a rubber skin, of course, and my temporary teeth weren't much of a fit. I had to do a kind of sawing movement before I could get my teeth through the skin. And then suddenly pop! The thing burst in my mouth like a rotten pear. A sort of horrible soft stuff was oozing all over my tongue. But the taste! For a moment I just couldn't believe it. Then I rolled my tongue around it again and had another try. It was fish! A sausage, a thing calling itself a frankfurter, filled with fish! I got up and walked straight out without touching my coffee. God knows what that might have tasted of.
Many other tell-tale elements of Orwell's fictional writing are in attendance in this book as well, albeit worked out somewhat less successfully than elsewhere in his oeuvre. For example, the idea of a physical ailment also serving as a metaphor is present in George's false teeth, embodying his constant preoccupation with his ageing. (Readers may recall Winston Smith's varicose ulcer representing his repressed humanity in Nineteen Eighty-Four). And, of course, we have a prematurely middle-aged protagonist who almost but not quite resembles Orwell himself. Given this and a few other niggles (such as almost all the women being of the typical Orwell 'nagging wife' type), it is not exactly Orwell's magnum opus. But it remains a fascinating historical snapshot of the feeling felt by a vast number of people just prior to the Second World War breaking out, as well as a captivating insight into how the process of nostalgia functions and operates.

Howards End (1910) E. M. Forster Howards End begins with the following sentence:
One may as well begin with Helen s letters to her sister.
In fact, "one may as well begin with" my own assumptions about this book instead. I was actually primed to consider Howards End a much more 'Victorian' book: I had just finished Virginia Woolf's Mrs Dalloway and had found her 1925 book at once rather 'modern' but also very much constrained by its time. I must have then unconsciously surmised that a book written 15 years before would be even more inscrutable, and, with its Victorian social mores added on as well, Howards End would probably not undress itself so readily in front of the reader. No doubt there were also the usual expectations about 'the classics' as well. So imagine my surprise when I realised just how inordinately affable and witty Howards End turned out to be. It doesn't have that Wildean shine of humour, of course, but it's a couple of fields over in the English countryside, perhaps abutting the more mordant social satires of the earlier George Orwell novels (see Coming Up for Air above). But now let us return to the story itself. Howards End explores class warfare, conflict and the English character through a tale of three quite different families at the beginning of the twentieth century: the rich Wilcoxes; the gentle & idealistic Schlegels; and the lower-middle class Basts. As the Bloomsbury Group Schlegel sisters desperately try to help the Basts and educate the rich but close-minded Wilcoxes, the three families are drawn ever closer and closer together. Although the whole story does, I suppose, revolve around the house in the title (which is based on the Forster's own childhood home), Howards End is perhaps best described as a comedy of manners or a novel that shows up the hypocrisy of people and society. In fact, it is surprising how little of the story actually takes place in the eponymous house, with the overwhelming majority of the first half of the book taking place in London. But it is perhaps more illuminating to remark that the Howards End of the book is a house that the Wilcoxes who own it at the start of the novel do not really need or want. What I particularly liked about Howards End is how the main character's ideals alter as they age, and subsequently how they find their lives changing in different ways. Some of them find themselves better off at the end, others worse. And whilst it is also surprisingly funny, it still manages to trade in heavier social topics as well. This is apparent in the fact that, although the characters themselves are primarily in charge of their own destinies, their choices are still constrained by the changing world and shifting sense of morality around them. This shouldn't be too surprising: after all, Forster's novel was published just four years before the Great War, a distinctly uncertain time. Not for nothing did Virginia Woolf herself later observe that "on or about December 1910, human character changed" and that "all human relations have shifted: those between masters and servants, husbands and wives, parents and children." This process can undoubtedly be seen rehearsed throughout Forster's Howards End, and it's a credit to the author to be able to capture it so early on, if not even before it was widespread throughout Western Europe. I was also particularly taken by Forster's fertile use of simile. An extremely apposite example can be found in the description Tibby Schlegel gives of his fellow Cambridge undergraduates. Here, Timmy doesn't want to besmirch his lofty idealisation of them with any banal specificities, and wishes that the idea of them remain as ideal Platonic forms instead. Or, as Forster puts it, to Timmy it is if they are "pictures that must not walk out of their frames." Wilde, at his most weakest, is 'just' style, but Forster often deploys his flair for a deeper effect. Indeed, when you get to the end of this section mentioning picture frames, you realise Forster has actually just smuggled into the story a failed attempt on Tibby's part to engineer an anonymous homosexual encounter with another undergraduate. It is a credit to Forster's sleight-of-hand that you don't quite notice what has just happened underneath you and that the books' reticence to honestly describe what has happened is thus structually analogus Tibby's reluctance to admit his desires to himself. Another layer to the character of Tibby (and the novel as a whole) is thereby introduced without the imposition of clumsy literary scaffolding. In a similar vein, I felt very clever noticing the arch reference to Debussy's Pr lude l'apr s-midi d'un faune until I realised I just fell into the trap Forster set for the reader in that I had become even more like Tibby in his pseudo-scholarly views on classical music. Finally, I enjoyed that each chapter commences with an ironic and self-conscious bon mot about society which is only slightly overblown for effect. Particularly amusing are the ironic asides on "women" that run through the book, ventriloquising the narrow-minded views of people like the Wilcoxes. The omniscient and amiable narrator of the book also recalls those ironically distant voiceovers from various French New Wave films at times, yet Forster's narrator seems to have bigger concerns in his mordant asides: Forster seems to encourage some sympathy for all of the characters even the more contemptible ones at their worst moments. Highly recommended, as are Forster's A Room with a View (1908) and his slightly later A Passage to India (1913).

The Good Soldier (1915) Ford Madox Ford The Good Soldier starts off fairly simply as the narrator's account of his and his wife's relationship with some old friends, including the eponymous 'Good Soldier' of the book's title. It's an experience to read the beginning of this novel, as, like any account of endless praise of someone you've never met or care about, the pages of approving remarks about them appear to be intended to wash over you. Yet as the chapters of The Good Soldier go by, the account of the other characters in the book gets darker and darker. Although the author himself is uncritical of others' actions, your own critical faculties are slowgrly brought into play, and you gradully begin to question the narrator's retelling of events. Our narrator is an unreliable narrator in the strict sense of the term, but with the caveat that he is at least is telling us everything we need to know to come to our own conclusions. As the book unfolds further, the narrator's compromised credibility seems to infuse every element of the novel even the 'Good' of the book's title starts to seem like a minor dishonesty, perhaps serving as the inspiration for the irony embedded in the title of The 'Great' Gatsby. Much more effectively, however, the narrator's fixations, distractions and manner of speaking feel very much part of his dissimulation. It sometimes feels like he is unconsciously skirting over the crucial elements in his tale, exactly like one does in real life when recounting a story containing incriminating ingredients. Indeed, just how much the narrator is conscious of his own concealment is just one part of what makes this such an interesting book: Ford Madox Ford has gifted us with enough ambiguity that it is also possible that even the narrator cannot find it within himself to understand the events of the story he is narrating. It was initially hard to believe that such a carefully crafted analysis of a small group of characters could have been written so long ago, and despite being fairly easy to read, The Good Soldier is an almost infinitely subtle book even the jokes are of the subtle kind and will likely get a re-read within the next few years.

Anna Karenina (1878) Leo Tolstoy There are many similar themes running through War and Peace (reviewed above) and Anna Karenina. Unrequited love; a young man struggling to find a purpose in life; a loving family; an overwhelming love of nature and countless fascinating observations about the minuti of Russian society. Indeed, rather than primarily being about the eponymous Anna, Anna Karenina provides a vast panorama of contemporary life in Russia and of humanity in general. Nevertheless, our Anna is a sophisticated woman who abandons her empty existence as the wife of government official Alexei Karenin, a colourless man who has little personality of his own, and she turns to a certain Count Vronsky in order to fulfil her passionate nature. Needless to say, this results in tragic consequences as their (admittedly somewhat qualified) desire to live together crashes against the rocks of reality and Russian society. Parallel to Anna's narrative, though, Konstantin Levin serves as the novel's alter-protagonist. In contrast to Anna, Levin is a socially awkward individual who straddles many schools of thought within Russia at the time: he is neither a free-thinker (nor heavy-drinker) like his brother Nikolai, and neither is he a bookish intellectual like his half-brother Serge. In short, Levin is his own man, and it is generally agreed by commentators that he is Tolstoy's surrogate within the novel. Levin tends to come to his own version of an idea, and he would rather find his own way than adopt any prefabricated view, even if confusion and muddle is the eventual result. In a roughly isomorphic fashion then, he resembles Anna in this particular sense, whose story is a counterpart to Levin's in their respective searches for happiness and self-actualisation. Whilst many of the passionate and exciting passages are told on Anna's side of the story (I'm thinking horse race in particular, as thrilling as anything in cinema ), many of the broader political thoughts about the nature of the working classes are expressed on Levin's side instead. These are stirring and engaging in their own way, though, such as when he joins his peasants to mow the field and seems to enter the nineteenth-century version of 'flow':
The longer Levin mowed, the more often he felt those moments of oblivion during which it was no longer his arms that swung the scythe, but the scythe itself that lent motion to his whole body, full of life and conscious of itself, and, as if by magic, without a thought of it, the work got rightly and neatly done on its own. These were the most blissful moments.
Overall, Tolstoy poses no didactic moral message towards any of the characters in Anna Karenina, and merely invites us to watch rather than judge. (Still, there is a hilarious section that is scathing of contemporary classical music, presaging many of the ideas found in Tolstoy's 1897 What is Art?). In addition, just like the earlier War and Peace, the novel is run through with a number of uncannily accurate observations about daily life:
Anna smiled, as one smiles at the weaknesses of people one loves, and, putting her arm under his, accompanied him to the door of the study.
... as well as the usual sprinkling of Tolstoy's sardonic humour ("No one is pleased with his fortune, but everyone is pleased with his wit."). Fyodor Dostoyevsky, the other titan of Russian literature, once described Anna Karenina as a "flawless work of art," and if you re only going to read one Tolstoy novel in your life, it should probably be this one.

10 November 2022

Alastair McKinstry: Government approves T&Cs for first offshore wind auction under the ...

Government approves T&Cs for first offshore wind auction under the Renewable Electricity Support Scheme ORESS 1 expected to secure 2.5GW of electricity generating capacity #GreensInGovernment The Government has today approved the Terms and Conditions of ORESS 1, the first auction for offshore wind under the Renewable Electricity Support Scheme. This is a seminal moment in the delivery of offshore wind in Ireland. The offshore auction, the first in Ireland's history, is expected to provide a route to market for up to 2.5GW of offshore renewable energy to the Irish grid, enough to power 2.5 million Irish homes with clean electricity. Coming during the weeks of COP27, publishing details of the auction sends a strong international signal that Ireland is serious about offshore energy and our national climate targets and obligations. Recognising the critical role of local hosting communities in the development of this critical infrastructure, all offshore wind projects developed via ORESS will be required to make Community Benefit Fund contributions, from construction phase and continuing for the duration of the support period, typically for a total period of 25 years. This will result in lasting, tangible benefits for these communities. Speaking about this development, Minister Ryan said: The publication of these ORESS 1 Terms and Conditions is another massive step forward for offshore wind, for Irish climate leadership and towards Ireland s future as an international green energy hub. The first stage of this transformative auction will start before Christmas and it sets us on a path to powering many more of our homes and businesses from our own green energy resources over the coming years. It follows the enactment of the Maritime Area Planning Act last year, and the announcement regarding the awarding of Maritime Area Consents to Phase One projects last month. A final ORESS 1 auction calendar will be published by EirGrid shortly. The pre-qualification stage will launch next month (December). The qualification stage and the auction process will take place in the first half of 2023. Final auction results will be published by June 2023. Eligible projects Any project that has been awarded a Maritime Area Consent is eligible to partake in the ORESS 1 auction. Seven projects known as Relevant Projects were deemed ready to apply for Maritime Area Consents in Spring 2022. Once Maritime Area Consents are granted, these projects can not only compete for State support via the ORESS, but can also apply for planning permission from An Bord Plean la. Delivering on our broader targets ORESS 1 is expected to procure approximately 2.5GW of electricity generating capacity. Further auctions will be required to meet our renewable energy and climate ambitions. At least three offshore energy auctions are currently planned for this decade. The aim is to progress enough viable offshore projects through the consenting system to have competitive auctions. This will ultimately drive down cost for electricity consumers.

3 November 2022

Arturo Borrero Gonz lez: New OpenPGP key and new email

Post logo I m trying to replace my old OpenPGP key with a new one. The old key wasn t compromised or lost or anything bad. Is still valid, but I plan to get rid of it soon. It was created in 2013. The new key id fingerprint is: AA66280D4EF0BFCC6BFC2104DA5ECB231C8F04C4 I plan to use the new key for things like encrypted emails, uploads to the Debian archive, and more. Also, the new key includes an identity with a newer personal email address I plan to use soon: arturo.bg@arturo.bg The new key has been uploaded to some public keyservers. If you would like to sign the new key, please follow the steps in the Debian wiki.
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-----END PGP PUBLIC KEY BLOCK-----
If you are curious about what that long code block contains, check this https://cirw.in/gpg-decoder/ For the record, the old key fingerprint is: DD9861AB23DC3333892E07A968E713981D1515F8 Cheers!

16 October 2022

Vincent Fourmond: Tutorial: analysis of multiwavelength fast kinetics data

The purpose of this post is to demonstrate a first approach to the analysis of multiwavelength kinetic data, like those obtained using stopped-flow data. To practice, we will use data that were acquired during the stopped flow practicals of the MetBio summer school from the FrenchBIC. During the practicals, the student monitored the reaction of myoglobin (in its Fe(III) state) with azide, which yields a fast and strong change in the absorbance spectrum of the protein, which was monitored using a diode array. The data is publicly available on zenodo. Aims of this tutorial The purpose of this tutorial is to teach you to use the free softwareQSoas to run a simple, multiwavelength exponential fit on the data, and to look at the results. This is not a kinetics lecture, so that it will not go in depth about the use of the exponential fit and its meaning. Getting started: loading the file First, make sure you have a working version of QSoas, you can download them (for free) there. Then download the data files from zenodo. We will work only on the data file Azide-1.25mm_001.dat, but of course, the purpose of this tutorial is to enable you to work on all of them. The data files contain the time evolution of the absorbance for all wavelengths, in a matrix format, in which each row correpond to a time point and each column to a wavelength. Start QSoas, and launch the command:
QSoas> load /comments='"'
Then, choose the Azide-1.25mm_001.dat data file. This should bring up a horizontal red line at the bottom of the data display, with X values between about 0 and 2.5. If you zoom on the red line with the mouse wheel, you'll realize it is data. The /comments='"' part is very important since it allows the extraction of the wavelength from the data. We will look at what it means another day. At this stage, you can look at the loaded data using the command:
QSoas> edit
You should have a window looking like this:
The rows each correspond to a data point displayed on the window below. The first column correspond to the X values, the second the Y values, and all the other ones to extra Y columns (they are not displayed by default). What is especially interesting is the first row, which contains a nan as the X value and what is obviously the wavelength for all the Y values. To tell that QSoas should take this line as the wavelength (which will be the perpendicular coordinate, the coordinate of the other direction of the matrix), first close the edit window and run:
QSoas> set-perp /from-row=0
Splitting and fitting Now, we have a single dataset containing a lot of Y columns. We want to fit all of them simultaneously with a (mono) exponential fit. For that, we first need to split the big matrix into a series of X,Y datasets (because fitting only works on the first Y). This is possible by running:
QSoas> expand /style=red-to-blue /flags=kinetics
Your screen should now look like this:
You're looking at the kinetics at all wavelengths at the same time (this may take some time to display on your computer, it is after all a rather large number of data points). The /style=red-to-blue is not strictly necessary, but it gives the red to blue color gradient which makes things easier to look at (and cooler !). The /flags=kinetics is there to attach a label (a flag) to the newly created datasets so we can easily manipulate all of them at the same time. Then it's time to fit, with the following command:
QSoas> mfit-exponential-decay flagged:kinetics
This should bring up a new window. After resizing it, you should have something that looks like this:
The bottom of the fit window is taken by the parameters, each with two checkboxes on the right to set them fixed (i.e. not determined by the fitting mechanism) and/or global (i.e. with a single value for all the datasets, here all the wavelengths). The top shows the current dataset along with the corresponding fit (in green), and, below, the residuals. You can change the dataset by clicking on the horizontal arrows or using Ctrl+PgUp or Ctrl+PgDown (keep holding it to scan fast). See the Z = 728.15 showing that QSoas has recognized that the currently displayed dataset corresponds to the wavelength 728.15. The equation fitted to the data is: $$y(x) = A_\infty + A_1 \times \exp -(x - x_0)/\tau_1$$ In this case, while the \(A_1\) and \(A_\infty\) parameters clearly depend on the wavelength, the time constant of evolution should be independent of wavelength (the process happens at a certain rate regardless of the wavelength we're analyzing), so that the \(\tau_1\) parameter should be common for all the datasets/wavelengths. Just click on the global checkbox at the right of the tau_1 parameter, make sure it is checked, and hit the Fit button... The fit should not take long (less than a minute), and then you end up with the results of the fits: all the parameters. The best way to look at the non global parameters like \(A_1\) and \(A_\infty\) is to use the Show Parameters item from the Parameters menu. Using it and clicking on A_inf too should give you a display like this one:
The A_inf parameter corresponds to the spectum at infinite time (of azide-bound heme), while the A_1 parameter corresponds to the difference spectrum between the initial (azide-free) and final (azide-bound) states. Now, the fit is finished, you can save the parameters if you want to reload them in a later fit by using the Parameters/Save menu item or export them in a form more suitable for plotting using Parameters/Export (although QSoas can also display and the parameters saved using Save). This concludes this first approach to fitting the data. What you can do is How to read the code above All the lines starting by QSoas> in the code areas above are meant to be typed into the QSoas command line (at the bottom of the window), and started by pressing enter at the end. You must remove the QSoas> bit. The other lines (when applicable) show you the response of QSoas, in the terminal just above the command-line. You may want to play with the QSoas tutorial to learn more about how to interact with QSoas. About QSoas QSoas is a powerful open source data analysis program that focuses on flexibility and powerful fitting capacities. It is released under the GNU General Public License. It is described in Fourmond, Anal. Chem., 2016, 88 (10), pp 5050 5052. Current version is 3.1. You can freely (and at no cost) download its source code or precompiled versions for MacOS and Windows there. Alternatively, you can clone from the GitHub repository.
Contact: find my email address there, or contact me on LinkedIn.

29 September 2022

Antoine Beaupr : Detecting manual (and optimizing large) package installs in Puppet

Well this is a mouthful. I recently worked on a neat hack called puppet-package-check. It is designed to warn about manually installed packages, to make sure "everything is in Puppet". But it turns out it can (probably?) dramatically decrease the bootstrap time of Puppet bootstrap when it needs to install a large number of packages.

Detecting manual packages On a cleanly filed workstation, it looks like this:
root@emma:/home/anarcat/bin# ./puppet-package-check -v
listing puppet packages...
listing apt packages...
loading apt cache...
0 unmanaged packages found
A messy workstation will look like this:
root@curie:/home/anarcat/bin# ./puppet-package-check -v
listing puppet packages...
listing apt packages...
loading apt cache...
288 unmanaged packages found
apparmor-utils beignet-opencl-icd bridge-utils clustershell cups-pk-helper davfs2 dconf-cli dconf-editor dconf-gsettings-backend ddccontrol ddrescueview debmake debootstrap decopy dict-devil dict-freedict-eng-fra dict-freedict-eng-spa dict-freedict-fra-eng dict-freedict-spa-eng diffoscope dnsdiag dropbear-initramfs ebtables efibootmgr elpa-lua-mode entr eog evince figlet file file-roller fio flac flex font-manager fonts-cantarell fonts-inconsolata fonts-ipafont-gothic fonts-ipafont-mincho fonts-liberation fonts-monoid fonts-monoid-tight fonts-noto fonts-powerline fonts-symbola freeipmi freetype2-demos ftp fwupd-amd64-signed gallery-dl gcc-arm-linux-gnueabihf gcolor3 gcp gdisk gdm3 gdu gedit gedit-plugins gettext-base git-debrebase gnome-boxes gnote gnupg2 golang-any golang-docker-credential-helpers golang-golang-x-tools grub-efi-amd64-signed gsettings-desktop-schemas gsfonts gstreamer1.0-libav gstreamer1.0-plugins-base gstreamer1.0-plugins-good gstreamer1.0-plugins-ugly gstreamer1.0-pulseaudio gtypist gvfs-backends hackrf hashcat html2text httpie httping hugo humanfriendly iamerican-huge ibus ibus-gtk3 ibus-libpinyin ibus-pinyin im-config imediff img2pdf imv initramfs-tools input-utils installation-birthday internetarchive ipmitool iptables iptraf-ng jackd2 jupyter jupyter-nbextension-jupyter-js-widgets jupyter-qtconsole k3b kbtin kdialog keditbookmarks keepassxc kexec-tools keyboard-configuration kfind konsole krb5-locales kwin-x11 leiningen lightdm lintian linux-image-amd64 linux-perf lmodern lsb-base lvm2 lynx lz4json magic-wormhole mailscripts mailutils manuskript mat2 mate-notification-daemon mate-themes mime-support mktorrent mp3splt mpdris2 msitools mtp-tools mtree-netbsd mupdf nautilus nautilus-sendto ncal nd ndisc6 neomutt net-tools nethogs nghttp2-client nocache npm2deb ntfs-3g ntpdate nvme-cli nwipe obs-studio okular-extra-backends openstack-clients openstack-pkg-tools paprefs pass-extension-audit pcmanfm pdf-presenter-console pdf2svg percol pipenv playerctl plymouth plymouth-themes popularity-contest progress prometheus-node-exporter psensor pubpaste pulseaudio python3-ldap qjackctl qpdfview qrencode r-cran-ggplot2 r-cran-reshape2 rake restic rhash rpl rpm2cpio rs ruby ruby-dev ruby-feedparser ruby-magic ruby-mocha ruby-ronn rygel-playbin rygel-tracker s-tui sanoid saytime scrcpy scrcpy-server screenfetch scrot sdate sddm seahorse shim-signed sigil smartmontools smem smplayer sng sound-juicer sound-theme-freedesktop spectre-meltdown-checker sq ssh-audit sshuttle stress-ng strongswan strongswan-swanctl syncthing system-config-printer system-config-printer-common system-config-printer-udev systemd-bootchart systemd-container tardiff task-desktop task-english task-ssh-server tasksel tellico texinfo texlive-fonts-extra texlive-lang-cyrillic texlive-lang-french texlive-lang-german texlive-lang-italian texlive-xetex tftp-hpa thunar-archive-plugin tidy tikzit tint2 tintin++ tipa tpm2-tools traceroute tree trocla ucf udisks2 unifont unrar-free upower usbguard uuid-runtime vagrant-cachier vagrant-libvirt virt-manager vmtouch vorbis-tools w3m wamerican wamerican-huge wfrench whipper whohas wireshark xapian-tools xclip xdg-user-dirs-gtk xlax xmlto xsensors xserver-xorg xsltproc xxd xz-utils yubioath-desktop zathura zathura-pdf-poppler zenity zfs-dkms zfs-initramfs zfsutils-linux zip zlib1g zlib1g-dev
157 old: apparmor-utils clustershell davfs2 dconf-cli dconf-editor ddccontrol ddrescueview decopy dnsdiag ebtables efibootmgr elpa-lua-mode entr figlet file-roller fio flac flex font-manager freetype2-demos ftp gallery-dl gcc-arm-linux-gnueabihf gcolor3 gcp gdu gedit git-debrebase gnote golang-docker-credential-helpers golang-golang-x-tools gtypist hackrf hashcat html2text httpie httping hugo humanfriendly iamerican-huge ibus ibus-pinyin imediff input-utils internetarchive ipmitool iptraf-ng jackd2 jupyter-qtconsole k3b kbtin kdialog keditbookmarks keepassxc kexec-tools kfind konsole leiningen lightdm lynx lz4json magic-wormhole manuskript mat2 mate-notification-daemon mktorrent mp3splt msitools mtp-tools mtree-netbsd nautilus nautilus-sendto nd ndisc6 neomutt net-tools nethogs nghttp2-client nocache ntpdate nwipe obs-studio openstack-pkg-tools paprefs pass-extension-audit pcmanfm pdf-presenter-console pdf2svg percol pipenv playerctl qjackctl qpdfview qrencode r-cran-ggplot2 r-cran-reshape2 rake restic rhash rpl rpm2cpio rs ruby-feedparser ruby-magic ruby-mocha ruby-ronn s-tui saytime scrcpy screenfetch scrot sdate seahorse shim-signed sigil smem smplayer sng sound-juicer spectre-meltdown-checker sq ssh-audit sshuttle stress-ng system-config-printer system-config-printer-common tardiff tasksel tellico texlive-lang-cyrillic texlive-lang-french tftp-hpa tikzit tint2 tintin++ tpm2-tools traceroute tree unrar-free vagrant-cachier vagrant-libvirt vmtouch vorbis-tools w3m wamerican wamerican-huge wfrench whipper whohas xdg-user-dirs-gtk xlax xmlto xsensors xxd yubioath-desktop zenity zip
131 new: beignet-opencl-icd bridge-utils cups-pk-helper dconf-gsettings-backend debmake debootstrap dict-devil dict-freedict-eng-fra dict-freedict-eng-spa dict-freedict-fra-eng dict-freedict-spa-eng diffoscope dropbear-initramfs eog evince file fonts-cantarell fonts-inconsolata fonts-ipafont-gothic fonts-ipafont-mincho fonts-liberation fonts-monoid fonts-monoid-tight fonts-noto fonts-powerline fonts-symbola freeipmi fwupd-amd64-signed gdisk gdm3 gedit-plugins gettext-base gnome-boxes gnupg2 golang-any grub-efi-amd64-signed gsettings-desktop-schemas gsfonts gstreamer1.0-libav gstreamer1.0-plugins-base gstreamer1.0-plugins-good gstreamer1.0-plugins-ugly gstreamer1.0-pulseaudio gvfs-backends ibus-gtk3 ibus-libpinyin im-config img2pdf imv initramfs-tools installation-birthday iptables jupyter jupyter-nbextension-jupyter-js-widgets keyboard-configuration krb5-locales kwin-x11 lintian linux-image-amd64 linux-perf lmodern lsb-base lvm2 mailscripts mailutils mate-themes mime-support mpdris2 mupdf ncal npm2deb ntfs-3g nvme-cli okular-extra-backends openstack-clients plymouth plymouth-themes popularity-contest progress prometheus-node-exporter psensor pubpaste pulseaudio python3-ldap ruby ruby-dev rygel-playbin rygel-tracker sanoid scrcpy-server sddm smartmontools sound-theme-freedesktop strongswan strongswan-swanctl syncthing system-config-printer-udev systemd-bootchart systemd-container task-desktop task-english task-ssh-server texinfo texlive-fonts-extra texlive-lang-german texlive-lang-italian texlive-xetex thunar-archive-plugin tidy tipa trocla ucf udisks2 unifont upower usbguard uuid-runtime virt-manager wireshark xapian-tools xclip xserver-xorg xsltproc xz-utils zathura zathura-pdf-poppler zfs-dkms zfs-initramfs zfsutils-linux zlib1g zlib1g-dev
Yuck! That's a lot of shit to go through. Notice how the packages get sorted between "old" and "new" packages. This is because popcon is used as a tool to mark which packages are "old". If you have unmanaged packages, the "old" ones are likely things that you can uninstall, for example. If you don't have popcon installed, you'll also get this warning:
popcon stats not available: [Errno 2] No such file or directory: '/var/log/popularity-contest'
The error can otherwise be safely ignored, but you won't get "help" prioritizing the packages to add to your manifests. Note that the tool ignores packages that were "marked" (see apt-mark(8)) as automatically installed. This implies that you might have to do a little bit of cleanup the first time you run this, as Debian doesn't necessarily mark all of those packages correctly on first install. For example, here's how it looks like on a clean install, after Puppet ran:
root@angela:/home/anarcat# ./bin/puppet-package-check -v
listing puppet packages...
listing apt packages...
loading apt cache...
127 unmanaged packages found
ca-certificates console-setup cryptsetup-initramfs dbus file gcc-12-base gettext-base grub-common grub-efi-amd64 i3lock initramfs-tools iw keyboard-configuration krb5-locales laptop-detect libacl1 libapparmor1 libapt-pkg6.0 libargon2-1 libattr1 libaudit-common libaudit1 libblkid1 libbpf0 libbsd0 libbz2-1.0 libc6 libcap-ng0 libcap2 libcap2-bin libcom-err2 libcrypt1 libcryptsetup12 libdb5.3 libdebconfclient0 libdevmapper1.02.1 libedit2 libelf1 libext2fs2 libfdisk1 libffi8 libgcc-s1 libgcrypt20 libgmp10 libgnutls30 libgpg-error0 libgssapi-krb5-2 libhogweed6 libidn2-0 libip4tc2 libiw30 libjansson4 libjson-c5 libk5crypto3 libkeyutils1 libkmod2 libkrb5-3 libkrb5support0 liblocale-gettext-perl liblockfile-bin liblz4-1 liblzma5 libmd0 libmnl0 libmount1 libncurses6 libncursesw6 libnettle8 libnewt0.52 libnftables1 libnftnl11 libnl-3-200 libnl-genl-3-200 libnl-route-3-200 libnss-systemd libp11-kit0 libpam-systemd libpam0g libpcre2-8-0 libpcre3 libpcsclite1 libpopt0 libprocps8 libreadline8 libselinux1 libsemanage-common libsemanage2 libsepol2 libslang2 libsmartcols1 libss2 libssl1.1 libssl3 libstdc++6 libsystemd-shared libsystemd0 libtasn1-6 libtext-charwidth-perl libtext-iconv-perl libtext-wrapi18n-perl libtinfo6 libtirpc-common libtirpc3 libudev1 libunistring2 libuuid1 libxtables12 libxxhash0 libzstd1 linux-image-amd64 logsave lsb-base lvm2 media-types mlocate ncurses-term pass-extension-otp puppet python3-reportbug shim-signed tasksel ucf usr-is-merged util-linux-extra wpasupplicant xorg zlib1g
popcon stats not available: [Errno 2] No such file or directory: '/var/log/popularity-contest'
Normally, there should be unmanaged packages here. But because of the way Debian is installed, a lot of libraries and some core packages are marked as manually installed, and are of course not managed through Puppet. There are two solutions to this problem:
  • really manage everything in Puppet (argh)
  • mark packages as automatically installed
I typically chose the second path and mark a ton of stuff as automatic. Then either they will be auto-removed, or will stop being listed. In the above scenario, one could mark all libraries as automatically installed with:
apt-mark auto $(./bin/puppet-package-check   grep -o 'lib[^ ]*')
... but if you trust that most of that stuff is actually garbage that you don't really want installed anyways, you could just mark it all as automatically installed:
apt-mark auto $(./bin/puppet-package-check)
In my case, that ended up keeping basically all libraries (because of course they're installed for some reason) and auto-removing this:
dh-dkms discover-data dkms libdiscover2 libjsoncpp25 libssl1.1 linux-headers-amd64 mlocate pass-extension-otp pass-otp plocate x11-apps x11-session-utils xinit xorg
You'll notice xorg in there: yep, that's bad. Not what I wanted. But for some reason, on other workstations, I did not actually have xorg installed. Turns out having xserver-xorg is enough, and that one has dependencies. So now I guess I just learned to stop worrying and live without X(org).

Optimizing large package installs But that, of course, is not all. Why make things simple when you can have an unreadable title that is trying to be both syntactically correct and click-baity enough to flatter my vain ego? Right. One of the challenges in bootstrapping Puppet with large package lists is that it's slow. Puppet lists packages as individual resources and will basically run apt install $PKG on every package in the manifest, one at a time. While the overhead of apt is generally small, when you add things like apt-listbugs, apt-listchanges, needrestart, triggers and so on, it can take forever setting up a new host. So for initial installs, it can actually makes sense to skip the queue and just install everything in one big batch. And because the above tool inspects the packages installed by Puppet, you can run it against a catalog and have a full lists of all the packages Puppet would install, even before I even had Puppet running. So when reinstalling my laptop, I basically did this:
apt install puppet-agent/experimental
puppet agent --test --noop
apt install $(./puppet-package-check --debug \
    2>&1   grep ^puppet\ packages 
      sed 's/puppet packages://;s/ /\n/g'
      grep -v -e onionshare -e golint -e git-sizer -e github-backup -e hledger -e xsane -e audacity -e chirp -e elpa-flycheck -e elpa-lsp-ui -e yubikey-manager -e git-annex -e hopenpgp-tools -e puppet
) puppet-agent/experimental
That massive grep was because there are currently a lot of packages missing from bookworm. Those are all packages that I have in my catalog but that still haven't made it to bookworm. Sad, I know. I eventually worked around that by adding bullseye sources so that the Puppet manifest actually ran. The point here is that this improves the Puppet run time a lot. All packages get installed at once, and you get a nice progress bar. Then you actually run Puppet to deploy configurations and all the other goodies:
puppet agent --test
I wish I could tell you how much faster that ran. I don't know, and I will not go through a full reinstall just to please your curiosity. The only hard number I have is that it installed 444 packages (which exploded in 10,191 packages with dependencies) in a mere 10 minutes. That might also be with the packages already downloaded. In any case, I have that gut feeling it's faster, so you'll have to just trust my gut. It is, after all, much more important than you might think.

Similar work The blueprint system is something similar to this:
It figures out what you ve done manually, stores it locally in a Git repository, generates code that s able to recreate your efforts, and helps you deploy those changes to production
That tool has unfortunately been abandoned for a decade at this point. Also note that the AutoRemove::RecommendsImportant and AutoRemove::SuggestsImportant are relevant here. If it is set to true (the default), a package will not be removed if it is (respectively) a Recommends or Suggests of another package (as opposed to the normal Depends). In other words, if you want to also auto-remove packages that are only Suggests, you would, for example, add this to apt.conf:
AutoRemove::SuggestsImportant false;
Paul Wise has tried to make the Debian installer and debootstrap properly mark packages as automatically installed in the past, but his bug reports were rejected. The other suggestions in this section are also from Paul, thanks!

28 September 2022

Vincent Fourmond: Version 3.1 of QSoas is out

The new version of QSoas has just been released ! It brings in a host of new features, as the releases before, but maybe the most important change is the following... Binary images now freely available ! Starting from now, all the binary images for the new versions of QSoas will freely available from the download page. You can download the precompiled versions of QSoas for MacOS or windows. So now, you have no reason anymore not to try !
My aim with making the binaries freely available is also to simplify the release process for me and therefore increase the rate at which new versions are released. Improvements to the fit interface Some work went into improving the fit interface, in particular for the handling of fit trajectories when doing parameter space exploration, for difficult fits with many parameters and many local minima. The fit window now features real menus, along with tab a way to display the terminal (see the menus and the tabs selection on the image).
Individual fits have also been improved, with, among others, the possibility to easily simulate voltammograms with the kinetic-system fits, and the handling of Marcus-Hush-Chidsey (or Marcus "distribution of states") kinetics for electron transfers. Column and row names This release greatly improves the handling of column and row names, including commands to easily modify them, the possibility to use Ruby formulas to change them, and a much better way read and write them to data files. Mastering the use of column names (and to a lesser extent, row names) can greatly simplify data handling, especially when dealing with files with a large number of columns. Complex numbers Version 3.1 brings in support for formulas handling complex numbers. Although it is not possible to store complex numbers directly into datasets, it is easy to separate them in real and imaginary parts to your liking. Scripting improvement Two important improvements for scripting are included in version 3.1. The first is the possibility to define virtual files inside a script file, which makes it easy to define subfunctions to run using commands like run-for-each. The second is the possibility to define variables to be reused later (like the script arguments) using the new command let. There are a lot of other new features, improvements and so on, look for the full list there. About QSoas
QSoas is a powerful open source data analysis program that focuses on flexibility and powerful fitting capacities. It is released under the GNU General Public License. It is described in Fourmond, Anal. Chem., 2016, 88 (10), pp 5050 5052. Current version is 3.1. You can download its source code or precompiled versions for MacOS and Windows there. Alternatively, you can clone from the GitHub repository.

22 September 2022

Jonathan Dowland: Nine Inch Nails, Cornwall, June

In June I travelled to see Nine Inch Nails perform two nights at the Eden Project in Cornwall. It'd been eight years since I last saw them live and when they announced the Eden shows, I thought it might be the only chance I'd get to see them for a long time. I committed, and sods law, a week or so later they announced a handful of single-night UK club shows. On the other hand, on previous tours where they'd typically book two club nights in each city, I've attended one night and always felt I should have done both, so this time I was making that happen. Newquay
approach by air approach by air
Towan Beach (I think) Towan Beach (I think)
For personal reasons it's been a difficult year so it was nice to treat myself to a mini holiday. I stayed in Newquay, a seaside town with many similarities to the North East coast, as well as many differences. It's much bigger, and although we have a thriving surfing community in Tynemouth, Newquay have it on another level. They also have a lot more tourism, which is a double-edged sword: in Newquay, besides surfing, there was not a lot to do. There's a lot of tourist tat shops, and bars and cafes (som very nice ones), but no book shops, no record shops, very few of the quaint, unique boutique places we enjoy up here and possibly take for granted. If you want tie-dyed t-shirts though, you're sorted. Nine Inch Nails have a long-established, independently fan-run forum called Echoing The Sound. There is now also an official Discord server. I asked on both whether anyone was around in Newquay and wanted to meet up: not many people were! But I did meet a new friend, James, for a quiet drink. He was due to share a taxi with Sarah, who was flying in but her flight was delayed and she had to figure out another route. Eden Project
the Eden Project the Eden Project
The Eden Project, the venue itself, is a fascinating place. I didn't realise until I'd planned most of my time there that the gig tickets granted you free entry into the Project on the day of the gig as well as the day after. It was quite tricky to get from Newquay to the Eden project, I would have been better off staying in St Austell itself perhaps, so I didn't take advantage of this, but I did have a couple of hours total to explore a little bit at the venue before the gig on each night. Friday 17th (sunny) Once I got to the venue I managed to meet up with several names from ETS and the Discord: James, Sarah (who managed to re-arrange flights), Pete and his wife (sorry I missed your name), Via Tenebrosa (she of crab hat fame), Dave (DaveDiablo), Elliot and his sister and finally James (sheapdean), someone who I've been talking to online for over a decade and finally met in person (and who taped both shows). I also tried to meet up with a friend from the Debian UK community (hi Lief) but I couldn't find him! Support for Friday was Nitzer Ebb, who I wasn't familiar with before. There were two men on stage, one operating instruments, the other singing. It was a tough time to warm up the crowd, the venue was still very empty and it was very bright and sunny, but I enjoyed what I was hearing. They're definitely on my list. I later learned that the band's regular singer (Doug McCarthy) was unable to make it, and so the guy I was watching (Bon Harris) was standing in for full vocal duties. This made the performance (and their subsequent one at Hellfest the week after) all the more impressive.
pic of the band
Via (with crab hat), Sarah, me (behind). pic by kraw Via (with crab hat), Sarah, me (behind). pic by kraw
(Day) and night one, Thursday, was very hot and sunny and the band seemed a little uncomfortable exposed on stage with little cover. Trent commented as such at least once. The setlist was eclectic: and I finally heard some of my white whale songs. Highlights for me were The Perfect Drug, which was unplayed from 1997-2018 and has now become a staple, and the second ever performance of Everything, the first being a few days earlier. Also notable was three cuts in a row from the last LP, Bad Witch, Heresy and Love Is Not Enough. Saturday 18th (rain)
with Elliot, before with Elliot, before
Day/night 2, Friday, was rainy all day. Support was Yves Tumor, who were an interesting clash of styles: a Prince/Bowie-esque inspired lead clashing with a rock-out lead guitarist styling himself similarly to Brian May. I managed to find Sarah, Elliot (new gig best-buddy), Via and James (sheapdean) again. Pete was at this gig too, but opted to take a more relaxed position than the rail this time. I also spent a lot of time talking to a Canadian guy on a press pass (both nights) that I'm ashamed to have forgotten his name. The dank weather had Nine Inch Nails in their element. I think night one had the more interesting setlist, but night two had the best performance, hands down. Highlights for me were mostly a string of heavier songs (in rough order of scarcity, from common to rarely played): wish, burn, letting you, reptile, every day is exactly the same, the line begins to blur, and finally, happiness in slavery, the first UK performance since 1994. This was a crushing set. A girl in front of me was really suffering with the cold and rain after waiting at the venue all day to get a position on the rail. I thought she was going to pass out. A roadie with NIN noticed, and came over and gave her his jacket. He said if she waited to the end of the show and returned his jacket he'd give her a setlist, and true to his word, he did. This was a really nice thing to happen and really gave the impression that the folks who work on these shows are caring people.
Yep I was this close Yep I was this close
A fuckin' rainbow! Photo by "Lazereth of Nazereth"
Afterwards Afterwards
Night two did have some gentler songs and moments to remember: a re-arranged Sanctified (which ended a nineteen-year hiatus in 2013) And All That Could Have Been (recorded 2002, first played 2018), La Mer, during which the rain broke and we were presented with a beautiful pink-hued rainbow. They then segued into Less Than, providing the comic moment of the night when Trent noticed the rainbow mid-song; now a meme that will go down in NIN fan history. Wrap-up This was a blow-out, once in a lifetime trip to go and see a band who are at the top of their career in terms of performance. One problem I've had with NIN gigs in the past is suffering gig flashback to them when I go to other (inferior) gigs afterwards, and I'm pretty sure I will have this problem again. Doing both nights was worth it, the two experiences were very different and each had its own unique moments. The venue was incredible, and Cornwall is (modulo tourist trap stuff) beautiful.

20 September 2022

Matthew Garrett: Handling WebAuthn over remote SSH connections

Being able to SSH into remote machines and do work there is great. Using hardware security tokens for 2FA is also great. But trying to use them both at the same time doesn't work super well, because if you hit a WebAuthn request on the remote machine it doesn't matter how much you mash your token - it's not going to work.

But could it?

The SSH agent protocol abstracts key management out of SSH itself and into a separate process. When you run "ssh-add .ssh/id_rsa", that key is being loaded into the SSH agent. When SSH wants to use that key to authenticate to a remote system, it asks the SSH agent to perform the cryptographic signatures on its behalf. SSH also supports forwarding the SSH agent protocol over SSH itself, so if you SSH into a remote system then remote clients can also access your keys - this allows you to bounce through one remote system into another without having to copy your keys to those remote systems.

More recently, SSH gained the ability to store SSH keys on hardware tokens such as Yubikeys. If configured appropriately, this means that even if you forward your agent to a remote site, that site can't do anything with your keys unless you physically touch the token. But out of the box, this is only useful for SSH keys - you can't do anything else with this support.

Well, that's what I thought, at least. And then I looked at the code and realised that SSH is communicating with the security tokens using the same library that a browser would, except it ensures that any signature request starts with the string "ssh:" (which a genuine WebAuthn request never will). This constraint can actually be disabled by passing -O no-restrict-websafe to ssh-agent, except that was broken until this weekend. But let's assume there's a glorious future where that patch gets backported everywhere, and see what we can do with it.

First we need to load the key into the security token. For this I ended up hacking up the Go SSH agent support. Annoyingly it doesn't seem to be possible to make calls to the agent without going via one of the exported methods here, so I don't think this logic can be implemented without modifying the agent module itself. But this is basically as simple as adding another key message type that looks something like:
type ecdsaSkKeyMsg struct  
       Type        string  sshtype:"17 25" 
       Curve       string
       PubKeyBytes []byte
       RpId        string
       Flags       uint8
       KeyHandle   []byte
       Reserved    []byte
       Comments    string
       Constraints []byte  ssh:"rest" 
 
Where Type is ssh.KeyAlgoSKECDSA256, Curve is "nistp256", RpId is the identity of the relying party (eg, "webauthn.io"), Flags is 0x1 if you want the user to have to touch the key, KeyHandle is the hardware token's representation of the key (basically an opaque blob that's sufficient for the token to regenerate the keypair - this is generally stored by the remote site and handed back to you when it wants you to authenticate). The other fields can be ignored, other than PubKeyBytes, which is supposed to be the public half of the keypair.

This causes an obvious problem. We have an opaque blob that represents a keypair. We don't have the public key. And OpenSSH verifies that PubKeyByes is a legitimate ecdsa public key before it'll load the key. Fortunately it only verifies that it's a legitimate ecdsa public key, and does nothing to verify that it's related to the private key in any way. So, just generate a new ECDSA key (ecdsa.GenerateKey(elliptic.P256(), rand.Reader)) and marshal it ( elliptic.Marshal(ecKey.Curve, ecKey.X, ecKey.Y)) and we're good. Pass that struct to ssh.Marshal() and then make an agent call.

Now you can use the standard agent interfaces to trigger a signature event. You want to pass the raw challenge (not the hash of the challenge!) - the SSH code will do the hashing itself. If you're using agent forwarding this will be forwarded from the remote system to your local one, and your security token should start blinking - touch it and you'll get back an ssh.Signature blob. ssh.Unmarshal() the Blob member to a struct like
type ecSig struct  
        R *big.Int
        S *big.Int
 
and then ssh.Unmarshal the Rest member to
type authData struct  
        Flags    uint8
        SigCount uint32
 
The signature needs to be converted back to a DER-encoded ASN.1 structure (eg,
var b cryptobyte.Builder
b.AddASN1(asn1.SEQUENCE, func(b *cryptobyte.Builder)  
        b.AddASN1BigInt(ecSig.R)
        b.AddASN1BigInt(ecSig.S)
 )
signatureDER, _ := b.Bytes()
, and then you need to construct the Authenticator Data structure. For this, take the RpId used earlier and generate the sha256. Append the one byte Flags variable, and then convert SigCount to big endian and append those 4 bytes. You should now have a 37 byte structure. This needs to be CBOR encoded (I used github.com/fxamacker/cbor and just called cbor.Marshal(data, cbor.EncOptions )).

Now base64 encode the sha256 of the challenge data, the DER-encoded signature and the CBOR-encoded authenticator data and you've got everything you need to provide to the remote site to satisfy the challenge.

There are alternative approaches - you can use USB/IP to forward the hardware token directly to the remote system. But that means you can't use it locally, so it's less than ideal. Or you could implement a proxy that communicates with the key locally and have that tunneled through to the remote host, but at that point you're just reinventing ssh-agent.

And you should bear in mind that the default behaviour of blocking this sort of request is for a good reason! If someone is able to compromise a remote system that you're SSHed into, they can potentially trick you into hitting the key to sign a request they've made on behalf of an arbitrary site. Obviously they could do the same without any of this if they've compromised your local system, but there is some additional risk to this. It would be nice to have sensible MAC policies that default-denied access to the SSH agent socket and only allowed trustworthy binaries to do so, or maybe have some sort of reasonable flatpak-style portal to gate access. For my threat model I think it's a worthwhile security tradeoff, but you should evaluate that carefully yourself.

Anyway. Now to figure out whether there's a reasonable way to get browsers to work with this.

comment count unavailable comments

15 September 2022

Joachim Breitner: rec-def: Dominators case study

More ICFP-inspired experiments using the rec-def library: In Norman Ramsey s very nice talk about his Functional Pearl Beyond Relooper: Recursive Translation of Unstructured Control Flow to Structured Control Flow , he had the following slide showing the equation for the dominators of a node in a graph:
Norman Ramsey shows a formula Norman Ramsey shows a formula
He said it s ICFP and I wanted to say the dominance relation has a beautiful set of equations you can read all these algorithms how to compute this, but the concept is simple . This made me wonder: If the concept is simple and this formula is beautiful shouldn t this be sufficient for the Haskell programmer to obtain the dominator relation, without reading all those algorithms? Before we start, we have to clarify the formula a bit: If a node is an entry node (no predecessors) then the big intersection is over the empty set, and that is not a well-defined concept. For these nodes, we need that big intersection to return the empty set, as entry nodes are not dominated by any other node. (Let s assume that the entry nodes are exactly those with no predecessors.) Let s try, first using plain Haskell data structures. We begin by implementing this big intersection operator on Data.Set, and also a function to find the predecessors of a node in a graph: Now we can write down the formula that Norman gave, quite elegantly: Does this work? It seems it does: But not surprising if you have read my previous blog posts it falls over once we have recursion: So let us reimplement it with Data.Recursive.Set. The hope is that we can simply replace the operations, and that now it can suddenly handle cyclic graphs as well. Let s see: It does! Well, it does return a result but it looks strange. Clearly node 3 and 4 are also dominated by 1, but the result does not reflect that. But the result is a solution to Norman s equation. Was the equation wrong? No, but we failed to notice that the desired solution is the largest, not the smallest. And Data.Recursive.Set calculates, as documented, the least fixed point. What now? Until the library has code for RDualSet a, we can work around this by using the dual formula to calculate the non-dominators. To do this, we
  • use union instead of intersection
  • delete instead of insert,
  • S.empty, use the set of all nodes (which requires some extra plumbing)
  • subtract the result from the set of all nodes to get the dominators
and thus the code turns into:
And with this, now we do get the correct result:
ghci> domintors3 [(1,2),(1,3),(2,4),(3,4),(4,3)]
fromList [(1,[1]),(2,[1,2]),(3,[1,3]),(4,[1,4])]
We worked a little bit on how to express the beautiful formula to Haskell, but at no point did we have to think about how to solve it. To me, this is the essence of declarative programming.

Matthew Garrett: git signatures with SSH certificates

Last night I complained that git's SSH signature format didn't support using SSH certificates rather than raw keys, and was swiftly corrected, once again highlighting that the best way to make something happen is to complain about it on the internet in order to trigger the universe to retcon it into existence to make you look like a fool. But anyway. Let's talk about making this work!

git's SSH signing support is actually just it shelling out to ssh-keygen with a specific set of options, so let's go through an example of this with ssh-keygen. First, here's my certificate:

$ ssh-keygen -L -f id_aurora-cert.pub
id_aurora-cert.pub:
Type: ecdsa-sha2-nistp256-cert-v01@openssh.com user certificate
Public key: ECDSA-CERT SHA256:(elided)
Signing CA: RSA SHA256:(elided)
Key ID: "mgarrett@aurora.tech"
Serial: 10505979558050566331
Valid: from 2022-09-13T17:23:53 to 2022-09-14T13:24:23
Principals:
mgarrett@aurora.tech
Critical Options: (none)
Extensions:
permit-agent-forwarding
permit-port-forwarding
permit-pty

Ok! Now let's sign something:

$ ssh-keygen -Y sign -f ~/.ssh/id_aurora-cert.pub -n git /tmp/testfile
Signing file /tmp/testfile
Write signature to /tmp/testfile.sig

To verify this we need an allowed signatures file, which should look something like:

*@aurora.tech cert-authority ssh-rsa AAA(elided)

Perfect. Let's verify it:

$ cat /tmp/testfile ssh-keygen -Y verify -f /tmp/allowed_signers -I mgarrett@aurora.tech -n git -s /tmp/testfile.sig
Good "git" signature for mgarrett@aurora.tech with ECDSA-CERT key SHA256:(elided)


Woo! So, how do we make use of this in git? Generating the signatures is as simple as

$ git config --global commit.gpgsign true
$ git config --global gpg.format ssh
$ git config --global user.signingkey /home/mjg59/.ssh/id_aurora-cert.pub


and then getting on with life. Any commits will now be signed with the provided certificate. Unfortunately, git itself won't handle verification of these - it calls ssh-keygen -Y find-principals which doesn't deal with wildcards in the allowed signers file correctly, and then falls back to verifying the signature without making any assertions about identity. Which means you're going to have to implement this in your own CI by extracting the commit and the signature, extracting the identity from the commit metadata and calling ssh-keygen on your own. But it can be made to work!

But why would you want to? The current approach of managing keys for git isn't ideal - you can kind of piggy-back off github/gitlab SSH key infrastructure, but if you're an enterprise using SSH certificates for access then your users don't necessarily have enrolled keys to start with. And using certificates gives you extra benefits, such as having your CA verify that keys are hardware-backed before issuing a cert. Want to ensure that whoever made a commit was actually on an authorised laptop? Now you can!

I'll probably spend a little while looking into whether it's plausible to make the git verification code work with certificates or whether the right thing is to fix up ssh-keygen -Y find-principals to work with wildcard identities, but either way it's probably not much effort to get this working out of the box.

Edit to add: thanks to this commenter for pointing out that current OpenSSH git actually makes this work already!

comment count unavailable comments

14 September 2022

Joachim Breitner: rec-def: Program analysis case study

At this week s International Conference on Functional Programming I showed my rec-def Haskell library to a few people. As this crowd appreciates writing compilers, and example from the realm of program analysis is quite compelling.

To Throw or not to throw Here is our little toy language to analyze: It has variables, lambdas and applications, non-recursive (lazy) let bindings and, so that we have something to analyze, a way to throw and to catch exceptions: Given such an expression, we would like to know whether it might throw an exception. Such an analysis is easy to write: We traverse the syntax tree, remembering in the env which of the variables may throw an exception: The most interesting case is the one for Let, where we extend the environment env with the information about the additional variable env_bind, which is calculated from analyzing the right-hand side e1. So far so good:
ghci> someVal = Lam "y" (Var "y")
ghci> canThrow1 $ Throw
True
ghci> canThrow1 $ Let "x" Throw someVal
False
ghci> canThrow1 $ Let "x" Throw (App (Var "x") someVal)
True

Let it rec To spice things up, let us add a recursive let to the language: How can we support this new constructor in canThrow1? Let use naively follow the pattern used for Let: Calculate the analysis information for the variables in env_bind, extend the environment with that, and pass it down: Note that, crucially, we use env', and not just env, when analyzing the right-hand sides. It has to be that way, as all the variables are in scope in all the right-hand sides. In a strict language, such a mutually recursive definition, where env_bind uses env' which uses env_bind is basically unthinkable. But in a lazy language like Haskell, it might just work. Unfortunately, it works only as long as the recursive bindings are not actually recursive, or if they are recursive, they are not used:
ghci> canThrow1 $ LetRec [("x", Throw)] (Var "x")
True
ghci> canThrow1 $ LetRec [("x", App (Var "y") someVal), ("y", Throw)] (Var "x")
True
ghci> canThrow1 $ LetRec [("x", App (Var "x") someVal), ("y", Throw)] (Var "y")
True
But with genuine recursion, it does not work, and simply goes into a recursive cycle:
ghci> canThrow1 $ LetRec [("x", App (Var "x") someVal), ("y", Throw)] (Var "x")
^CInterrupted.
That is disappointing! Do we really have to toss that code and somehow do an explicit fixed-point calculation here? Obscuring our nice declarative code? And possibly having to repeat work (such as traversing the syntax tree) many times that we should only have to do once?

rec-def to the rescue Not with rec-def! Using RBool from Data.Recursive.Bool instead of Bool, we can write the exact same code, as follows: And it works!
ghci> canThrow2 $ LetRec [("x", App (Var "x") someVal), ("y", Throw)] (Var "x")
False
ghci> canThrow2 $ LetRec [("x", App (Var "x") Throw), ("y", Throw)] (Var "x")
True
I find this much more pleasing than the explicit naive fix-pointing you might do otherwise, where you stabilize the result at each LetRec independently: Not only is all that extra work hidden from the programmer, but now also a single traversal of the syntax tree creates, thanks to the laziness, a graph of RBool values, which are then solved under the hood .

The issue with x=x There is one downside worth mentioning: canThrow2 fails to produce a result in case we hit x=x:
ghci> canThrow2 $ LetRec [("x", Var "x")] (Var "x")
^CInterrupted.
This is, after all the syntax tree has been processed and all the map lookups have been resolved, equivalent to
ghci> let x = x in RB.get (x :: RBool)
^CInterrupted.
which also does not work. The rec-def machinery can only kick in if at least one of its function is used on any such cycle, even if it is just a form of identity (which I ~ought to add to the library~ since have added to the library):
ghci> idR x = RB.false   x
ghci> let x = idR x in getR (x :: R Bool)
False
And indeed, if I insert a call to idR in the line then our analyzer will no longer stumble over these nasty recursive equations:
ghci> canThrow2 $ LetRec [("x", Var "x")] (Var "x")
False
It is a bit disappointing to have to do that, but I do not see a better way yet. I guess the def-rec library expects the programmer to have a similar level of sophistication as other tie-the-know tricks with laziness (where you also have to ensure that your definitions are productive and that the sharing is not accidentally lost).

29 June 2022

Aigars Mahinovs: Long travel in an electric car

Since the first week of April 2022 I have (finally!) changed my company car from a plug-in hybrid to a fully electic car. My new ride, for the next two years, is a BMW i4 M50 in Aventurine Red metallic. An ellegant car with very deep and memorable color, insanely powerful (544 hp/795 Nm), sub-4 second 0-100 km/h, large 84 kWh battery (80 kWh usable), charging up to 210 kW, top speed of 225 km/h and also very efficient (which came out best in this trip) with WLTP range of 510 km and EVDB real range of 435 km. The car also has performance tyres (Hankook Ventus S1 evo3 245/45R18 100Y XL in front and 255/45R18 103Y XL in rear all at recommended 2.5 bar) that have reduced efficiency. So I wanted to document and describe how was it for me to travel ~2000 km (one way) with this, electric, car from south of Germany to north of Latvia. I have done this trip many times before since I live in Germany now and travel back to my relatives in Latvia 1-2 times per year. This was the first time I made this trip in an electric car. And as this trip includes both travelling in Germany (where BEV infrastructure is best in the world) and across Eastern/Northen Europe, I believe that this can be interesting to a few people out there. Normally when I travelled this trip with a gasoline/diesel car I would normally drive for two days with an intermediate stop somewhere around Warsaw with about 12 hours of travel time in each day. This would normally include a couple bathroom stops in each day, at least one longer lunch stop and 3-4 refueling stops on top of that. Normally this would use at least 6 liters of fuel per 100 km on average with total usage of about 270 liters for the whole trip (or about 540 just in fuel costs, nowadays). My (personal) quirk is that both fuel and recharging of my (business) car inside Germany is actually paid by my employer, so it is useful for me to charge up (or fill up) at the last station in Gemany before driving on. The plan for this trip was made in a similar way as when travelling with a gasoline car: travelling as fast as possible on German Autobahn network to last chargin stop on the A4 near G rlitz, there charging up as much as reasonable and then travelling to a hotel in Warsaw, charging there overnight and travelling north towards Ionity chargers in Lithuania from where reaching the final target in north of Latvia should be possible. How did this plan meet the reality? Travelling inside Germany with an electric car was basically perfect. The most efficient way would involve driving fast and hard with top speed of even 180 km/h (where possible due to speed limits and traffic). BMW i4 is very efficient at high speeds with consumption maxing out at 28 kWh/100km when you actually drive at this speed all the time. In real situation in this trip we saw consumption of 20.8-22.2 kWh/100km in the first legs of the trip. The more traffic there is, the more speed limits and roadworks, the lower is the average speed and also the lower the consumption. With this kind of consumption we could comfortably drive 2 hours as fast as we could and then pick any fast charger along the route and in 26 minutes at a charger (50 kWh charged total) we'd be ready to drive for another 2 hours. This lines up very well with recommended rest stops for biological reasons (bathroom, water or coffee, a bit of movement to get blood circulating) and very close to what I had to do anyway with a gasoline car. With a gasoline car I had to refuel first, then park, then go to bathroom and so on. With an electric car I can do all of that while the car is charging and in the end the total time for a stop is very similar. Also not that there was a crazy heat wave going on and temperature outside was at about 34C minimum the whole day and hitting 40C at one point of the trip, so a lot of power was used for cooling. The car has a heat pump standard, but it still was working hard to keep us cool in the sun. The car was able to plan a charging route with all the charging stops required and had all the good options (like multiple intermediate stops) that many other cars (hi Tesla) and mobile apps (hi Google and Apple) do not have yet. There are a couple bugs with charging route and display of current route guidance, those are already fixed and will be delivered with over the air update with July 2022 update. Another good alterantive is the ABRP (A Better Route Planner) that was specifically designed for electric car routing along the best route for charging. Most phone apps (like Google Maps) have no idea about your specific electric car - it has no idea about the battery capacity, charging curve and is missing key live data as well - what is the current consumption and remaining energy in the battery. ABRP is different - it has data and profiles for almost all electric cars and can also be linked to live vehicle data, either via a OBD dongle or via a new Tronity cloud service. Tronity reads data from vehicle-specific cloud service, such as MyBMW service, saves it, tracks history and also re-transmits it to ABRP for live navigation planning. ABRP allows for options and settings that no car or app offers, for example, saying that you want to stop at a particular place for an hour or until battery is charged to 90%, or saying that you have specific charging cards and would only want to stop at chargers that support those. Both the car and the ABRP also support alternate routes even with multiple intermediate stops. In comparison, route planning by Google Maps or Apple Maps or Waze or even Tesla does not really come close. After charging up in the last German fast charger, a more interesting part of the trip started. In Poland the density of high performance chargers (HPC) is much lower than in Germany. There are many chargers (west of Warsaw), but vast majority of them are (relatively) slow 50kW chargers. And that is a difference between putting 50kWh into the car in 23-26 minutes or in 60 minutes. It does not seem too much, but the key bit here is that for 20 minutes there is easy to find stuff that should be done anyway, but after that you are done and you are just waiting for the car and if that takes 4 more minutes or 40 more minutes is a big, perceptual, difference. So using HPC is much, much preferable. So we put in the Ionity charger near Lodz as our intermediate target and the car suggested an intermediate stop at a Greenway charger by Katy Wroclawskie. The location is a bit weird - it has 4 charging stations with 150 kW each. The weird bits are that each station has two CCS connectors, but only one parking place (and the connectors share power, so if two cars were to connect, each would get half power). Also from the front of the location one can only see two stations, the otehr two are semi-hidden around a corner. We actually missed them on the way to Latvia and one person actually waited for the charger behind us for about 10 minutes. We only discovered the other two stations on the way back. With slower speeds in Poland the consumption goes down to 18 kWh/100km which translates to now up to 3 hours driving between stops. At the end of the first day we drove istarting from Ulm from 9:30 in the morning until about 23:00 in the evening with total distance of about 1100 km, 5 charging stops, starting with 92% battery, charging for 26 min (50 kWh), 33 min (57 kWh + lunch), 17 min (23 kWh), 12 min (17 kWh) and 13 min (37 kW). In the last two chargers you can see the difference between a good and fast 150 kW charger at high battery charge level and a really fast Ionity charger at low battery charge level, which makes charging faster still. Arriving to hotel with 23% of battery. Overnight the car charged from a Porsche Destination Charger to 87% (57 kWh). That was a bit less than I would expect from a full power 11kW charger, but good enough. Hotels should really install 11kW Type2 chargers for their guests, it is a really significant bonus that drives more clients to you. The road between Warsaw and Kaunas is the most difficult part of the trip for both driving itself and also for charging. For driving the problem is that there will be a new highway going from Warsaw to Lithuanian border, but it is actually not fully ready yet. So parts of the way one drives on the new, great and wide highway and parts of the way one drives on temporary roads or on old single lane undivided roads. And the most annoying part is navigating between parts as signs are not always clear and the maps are either too old or too new. Some maps do not have the new roads and others have on the roads that have not been actually build or opened to traffic yet. It's really easy to loose ones way and take a significant detour. As far as charging goes, basically there is only the slow 50 kW chargers between Warsaw and Kaunas (for now). We chose to charge on the last charger in Poland, by Suwalki Kaufland. That was not a good idea - there is only one 50 kW CCS and many people decide the same, so there can be a wait. We had to wait 17 minutes before we could charge for 30 more minutes just to get 18 kWh into the battery. Not the best use of time. On the way back we chose a different charger in Lomza where would have a relaxed dinner while the car was charging. That was far more relaxing and a better use of time. We also tried charging at an Orlen charger that was not recommended by our car and we found out why. Unlike all other chargers during our entire trip, this charger did not accept our universal BMW Charging RFID card. Instead it demanded that we download their own Orlen app and register there. The app is only available in some countries (and not in others) and on iPhone it is only available in Polish. That is a bad exception to the rule and a bad example. This is also how most charging works in USA. Here in Europe that is not normal. The normal is to use a charging card - either provided from the car maker or from another supplier (like PlugSufring or Maingau Energy). The providers then make roaming arrangements with all the charging networks, so the cards just work everywhere. In the end the user gets the prices and the bills from their card provider as a single monthly bill. This also saves all any credit card charges for the user. Having a clear, separate RFID card also means that one can easily choose how to pay for each charging session. For example, I have a corporate RFID card that my company pays for (for charging in Germany) and a private BMW Charging card that I am paying myself for (for charging abroad). Having the car itself authenticate direct with the charger (like Tesla does) removes the option to choose how to pay. Having each charge network have to use their own app or token bring too much chaos and takes too much setup. The optimum is having one card that works everywhere and having the option to have additional card or cards for specific purposes. Reaching Ionity chargers in Lithuania is again a breath of fresh air - 20-24 minutes to charge 50 kWh is as expected. One can charge on the first Ionity just enough to reach the next one and then on the second charger one can charge up enough to either reach the Ionity charger in Adazi or the final target in Latvia. There is a huge number of CSDD (Road Traffic and Safety Directorate) managed chargers all over Latvia, but they are 50 kW chargers. Good enough for local travel, but not great for long distance trips. BMW i4 charges at over 50 kW on a HPC even at over 90% battery state of charge (SoC). This means that it is always faster to charge up in a HPC than in a 50 kW charger, if that is at all possible. We also tested the CSDD chargers - they worked without any issues. One could pay with the BMW Charging RFID card, one could use the CSDD e-mobi app or token and one could also use Mobilly - an app that you can use in Latvia for everything from parking to public transport tickets or museums or car washes. We managed to reach our final destination near Aluksne with 17% range remaining after just 3 charging stops: 17+30 min (18 kWh), 24 min (48 kWh), 28 min (36 kWh). Last stop we charged to 90% which took a few extra minutes that would have been optimal. For travel around in Latvia we were charging at our target farmhouse from a normal 3 kW Schuko EU socket. That is very slow. We charged for 33 hours and went from 17% to 94%, so not really full. That was perfectly fine for our purposes. We easily reached Riga, drove to the sea and then back to Aluksne with 8% still in reserve and started charging again for the next trip. If it were required to drive around more and charge faster, we could have used the normal 3-phase 440V connection in the farmhouse to have a red CEE 16A plug installed (same as people use for welders). BMW i4 comes standard with a new BMW Flexible Fast Charger that has changable socket adapters. It comes by default with a Schucko connector in Europe, but for 90 one can buy an adapter for blue CEE plug (3.7 kW) or red CEE 16A or 32A plugs (11 kW). Some public charging stations in France actually use the blue CEE plugs instead of more common Type2 electric car charging stations. The CEE plugs are also common in camping parking places. On the way back the long distance BEV travel was already well understood and did not cause us any problem. From our destination we could easily reach the first Ionity in Lithuania, on the Panevezhis bypass road where in just 8 minutes we got 19 kWh and were ready to drive on to Kaunas, there a longer 32 minute stop before the charging desert of Suwalki Gap that gave us 52 kWh to 90%. That brought us to a shopping mall in Lomzha where we had some food and charged up 39 kWh in lazy 50 minutes. That was enough to bring us to our return hotel for the night - Hotel 500W in Strykow by Lodz that has a 50kW charger on site, while we were having late dinner and preparing for sleep, the car easily recharged to full (71 kWh in 95 minutes), so I just moved it from charger to a parking spot just before going to sleep. Really easy and well flowing day. Second day back went even better as we just needed an 18 minute stop at the same Katy Wroclawskie charger as before to get 22 kWh and that was enough to get back to Germany. After that we were again flying on the Autobahn and charging as needed, 15 min (31 kWh), 23 min (48 kWh) and 31 min (54 kWh + food). We started the day on about 9:40 and were home at 21:40 after driving just over 1000 km on that day. So less than 12 hours for 1000 km travelled, including all charging, bio stops, food and some traffic jams as well. Not bad. Now let's take a look at all the apps and data connections that a technically minded customer can have for their car. Architecturally the car is a network of computers by itself, but it is very secured and normally people do not have any direct access. However, once you log in into the car with your BMW account the car gets your profile info and preferences (seat settings, navigation favorites, ...) and the car then also can start sending information to the BMW backend about its status. This information is then available to the user over multiple different channels. There is no separate channel for each of those data flow. The data only goes once to the backend and then all other communication of apps happens with the backend. First of all the MyBMW app. This is the go-to for everything about the car - seeing its current status and location (when not driving), sending commands to the car (lock, unlock, flash lights, pre-condition, ...) and also monitor and control charging processes. You can also plan a route or destination in the app in advance and then just send it over to the car so it already knows where to drive to when you get to the car. This can also integrate with calendar entries, if you have locations for appointments, for example. This also shows full charging history and allows a very easy export of that data, here I exported all charging sessions from June and then trimmed it back to only sessions relevant to the trip and cut off some design elements to have the data more visible. So one can very easily see when and where we were charging, how much power we got at each spot and (if you set prices for locations) can even show costs. I've already mentioned the Tronity service and its ABRP integration, but it also saves the information that it gets from the car and gathers that data over time. It has nice aspects, like showing the driven routes on a map, having ways to do business trip accounting and having good calendar view. Sadly it does not correctly capture the data for charging sessions (the amounts are incorrect). Update: after talking to Tronity support, it looks like the bug was in the incorrect value for the usable battery capacity for my car. They will look into getting th eright values there by default, but as a workaround one can edit their car in their system (after at least one charging session) and directly set the expected battery capacity (usable) in the car properties on the Tronity web portal settings. One other fun way to see data from your BMW is using the BMW integration in Home Assistant. This brings the car as a device in your own smart home. You can read all the variables from the car current status (and Home Asisstant makes cute historical charts) and you can even see interesting trends, for example for remaining range shows much higher value in Latvia as its prediction is adapted to Latvian road speeds and during the trip it adapts to Polish and then to German road speeds and thus to higher consumption and thus lower maximum predicted remaining range. Having the car attached to the Home Assistant also allows you to attach the car to automations, both as data and event source (like detecting when car enters the "Home" zone) and also as target, so you could flash car lights or even unlock or lock it when certain conditions are met. So, what in the end was the most important thing - cost of the trip? In total we charged up 863 kWh, so that would normally cost one about 290 , which is close to half what this trip would have costed with a gasoline car. Out of that 279 kWh in Germany (paid by my employer) and 154 kWh in the farmhouse (paid by our wonderful relatives :D) so in the end the charging that I actually need to pay adds up to 430 kWh or about 150 . Typically, it took about 400 in fuel that I had to pay to get to Latvia and back. The difference is really nice! In the end I believe that there are three different ways of charging:
  • incidental charging - this is wast majority of charging in the normal day-to-day life. The car gets charged when and where it is convinient to do so along the way. If we go to a movie or a shop and there is a chance to leave the car at a charger, then it can charge up. Works really well, does not take extra time for charging from us.
  • fast charging - charging up at a HPC during optimal charging conditions - from relatively low level to no more than 70-80% while you are still doing all the normal things one would do in a quick stop in a long travel process: bio things, cleaning the windscreen, getting a coffee or a snack.
  • necessary charging - charging from a whatever charger is available just enough to be able to reach the next destination or the next fast charger.
The last category is the only one that is really annoying and should be avoided at all costs. Even by shifting your plans so that you find something else useful to do while necessary charging is happening and thus, at least partially, shifting it over to incidental charging category. Then you are no longer just waiting for the car, you are doing something else and the car magically is charged up again. And when one does that, then travelling with an electric car becomes no more annoying than travelling with a gasoline car. Having more breaks in a trip is a good thing and makes the trips actually easier and less stressfull - I was more relaxed during and after this trip than during previous trips. Having the car air conditioning always be on, even when stopped, was a godsend in the insane heat wave of 30C-38C that we were driving trough. Final stats: 4425 km driven in the trip. Average consumption: 18.7 kWh/100km. Time driving: 2 days and 3 hours. Car regened 152 kWh. Charging stations recharged 863 kWh. Questions? You can use this i4talk forum thread or this Twitter thread to ask them to me.

25 June 2022

Ryan Kavanagh: Routable network addresses with OpenIKED and systemd-networkd

I ve been using OpenIKED for some time now to configure my VPN. One of its features is that it can dynamically assign addresses on the internal network to clients, and clients can assign these addresses and routes to interfaces. However, these interfaces must exist before iked can start. Some months ago I switched my Debian laptop s configuration from the traditional ifupdown to systemd-networkd. It took me some time to figure out how to have systemd-networkd create dummy interfaces on which iked can install addresses, but also not interfere with iked by trying to manage these interfaces. Here is my working configuration. First, I have systemd create the interface dummy1 by creating a systemd.netdev(5) configuration file at /etc/systemd/network/20-dummy1.netdev:
[NetDev]
Name=dummy1
Kind=dummy 
Then I tell systemd not to manage this interface by creating a systemd.network(5) configuration file at /etc/systemd/network/20-dummy1.network:
[Match]
Name=dummy1
Unmanaged=yes
Restarting systemd-networkd causes these interfaces to get created, and we can then check their status using networkctl(8):
$ systemctl restart systemd-networkd.service
$ networkctl
IDX LINK     TYPE     OPERATIONAL SETUP
  1 lo       loopback carrier     unmanaged
  2 enp2s0f0 ether    off         unmanaged
  3 enp5s0   ether    off         unmanaged
  4 dummy1   ether    degraded    configuring
  5 dummy3   ether    degraded    configuring
  6 sit0     sit      off         unmanaged
  8 wlp3s0   wlan     routable    configured
  9 he-ipv6  sit      routable    configured

8 links listed.
Finally, I configure my flows in /etc/iked.conf, making sure to assign the received address to the interface dummy1.
ikev2 'hades' active esp \
        from dynamic to 10.0.1.0/24 \
        peer hades.rak.ac \
        srcid '/CN=asteria.rak.ac' \
        dstid '/CN=hades.rak.ac' \
        request address 10.0.1.103 \
        iface dummy1
Restarting openiked and checking the status of the interface reveals that it has been assigned an address on the internal network and that it is routable:
$ systemctl restart openiked.service
$ networkctl status dummy1
  4: dummy1
                     Link File: /usr/lib/systemd/network/99-default.link
                  Network File: /etc/systemd/network/20-dummy1.network
                          Type: ether
                          Kind: dummy
                         State: routable (configured)
                  Online state: online
                        Driver: dummy
              Hardware Address: 22:50:5f:98:a1:a9
                           MTU: 1500
                         QDisc: noqueue
  IPv6 Address Generation Mode: eui64
          Queue Length (Tx/Rx): 1/1
                       Address: 10.0.1.103
                                fe80::2050:5fff:fe98:a1a9
                           DNS: 10.0.1.1
                 Route Domains: .
             Activation Policy: up
           Required For Online: yes
             DHCP6 Client DUID: DUID-EN/Vendor:0000ab11aafa4f02d6ac68d40000
I d be happy to hear if there are simpler or more idiomatic ways to configure this under systemd.

19 June 2022

John Goerzen: Pipes, deadlocks, and strace annoyingly fixing them

This is a complex tale I will attempt to make simple(ish). I ve (re)learned more than I cared to about the details of pipes, signals, and certain system calls and the solution is still elusive. For some time now, I have been using NNCP to back up my files. These backups are sent to my backup system, which effectively does this to process them (each ZFS send is piped to a shell script that winds up running this):
gpg -q -d   zstdcat -T0   zfs receive -u -o readonly=on "$STORE/$DEST"
This processes tens of thousands of zfs sends per week. Recently, having written Filespooler, I switched to sending the backups using Filespooler over NNCP. Now fspl (the Filespooler executable) opens the file for each stream and then connects it to what amounts to this pipeline:
bash -c 'gpg -q -d 2>/dev/null   zstdcat -T0'   zfs receive -u -o readonly=on "$STORE/$DEST"
Actually, to be more precise, it spins up the bash part of it, reads a few bytes from it, and then connects it to the zfs receive. And this works well almost always. In something like 1/1000 of the cases, it deadlocks, and I still don t know why. But I can talk about the journey of trying to figure it out (and maybe some of you will have some ideas). Filespooler is written in Rust, and uses Rust s Command system. Effectively what happens is this:
  1. The fspl process has a File handle, which after forking but before invoking bash, it dup2 s to stdin.
  2. The connection between bash and zfs receive is a standard Unix pipe.
I cannot get the problem to duplicate when I run the entire thing under strace -f. So I am left trying to peek at it from the outside. What happens if I try to attach to each component with strace -p? So the plot thickens! Why would connecting to zstdcat and zfs receive cause them to actually change behavior? strace works by using the ptrace system call, and ptrace in a number of cases requires sending SIGSTOP to a process. In a complicated set of circumstances, a system call may return EINTR when a SIGSTOP is received, with the idea that the system call should be retried. I can t see, from either zstdcat or zfs, if this is happening, though. So I thought, how about having Filespooler manually copy data from bash to zfs receive in a read/write loop instead of having them connected directly via a pipe? That is, there would be two pipes going there: one where Filespooler reads from the bash command, and one where it writes to zfs. If nothing else, I could instrument it with debugging. And so I did, and I found that when it deadlocked, it was deadlocking on write but with no discernible pattern as to where or when. So I went back to directly connected. In analyzing straces, I found a Rust bug which I reported in which it is failing to close the read end of a pipe in the parent post-fork. However, having implemented a workaround for this, it doesn t prevent the deadlock so this is orthogonal to the issue at hand. Among the two strange things here are things returning to normal when I attach strace to zstdcat, and things crashing when I attach strace to zfs. I decided to investigate the latter. It turns out that the ZFS code that is reading from stdin during zfs receive is in the kernel module, not userland. Here is the part that is triggering the imcomplete stream error:
                int err = zfs_file_read(fp, (char *)buf + done,
                    len - done, &resid);
                if (resid == len - done)  
                        /*
                         * Note: ECKSUM or ZFS_ERR_STREAM_TRUNCATED indicates
                         * that the receive was interrupted and can
                         * potentially be resumed.
                         */
                        err = SET_ERROR(ZFS_ERR_STREAM_TRUNCATED);
                 
resid is an output parameter with the number of bytes remaining from a short read, so in this case, if the read produced zero bytes, then it sets that error. What s zfs_file_read then? It boils down to a thin wrapper around kernel_read(). This winds up calling __kernel_read(), which calls read_iter on the pipe, which is pipe_read(). That s where I don t have the knowledge to get into the weeds right now. So it seems likely to me that the problem has something to do with zfs receive. But, what, and why does it only not work in this one very specific situation, and only so rarely? And why does attaching strace to zstdcat make it all work again? I m indeed puzzled! Update 2022-06-20: See the followup post which identifies this as likely a kernel bug and explains why this particular use of Filespooler made it easier to trigger.

17 June 2022

Antoine Beaupr : Matrix notes

I have some concerns about Matrix (the protocol, not the movie that came out recently, although I do have concerns about that as well). I've been watching the project for a long time, and it seems more a promising alternative to many protocols like IRC, XMPP, and Signal. This review may sound a bit negative, because it focuses on those concerns. I am the operator of an IRC network and people keep asking me to bridge it with Matrix. I have myself considered just giving up on IRC and converting to Matrix. This space is a living document exploring my research of that problem space. The TL;DR: is that no, I'm not setting up a bridge just yet, and I'm still on IRC. This article was written over the course of the last three months, but I have been watching the Matrix project for years (my logs seem to say 2016 at least). The article is rather long. It will likely take you half an hour to read, so copy this over to your ebook reader, your tablet, or dead trees, and lean back and relax as I show you around the Matrix. Or, alternatively, just jump to a section that interest you, most likely the conclusion.

Introduction to Matrix Matrix is an "open standard for interoperable, decentralised, real-time communication over IP. It can be used to power Instant Messaging, VoIP/WebRTC signalling, Internet of Things communication - or anywhere you need a standard HTTP API for publishing and subscribing to data whilst tracking the conversation history". It's also (when compared with XMPP) "an eventually consistent global JSON database with an HTTP API and pubsub semantics - whilst XMPP can be thought of as a message passing protocol." According to their FAQ, the project started in 2014, has about 20,000 servers, and millions of users. Matrix works over HTTPS but over a special port: 8448.

Security and privacy I have some concerns about the security promises of Matrix. It's advertised as a "secure" with "E2E [end-to-end] encryption", but how does it actually work?

Data retention defaults One of my main concerns with Matrix is data retention, which is a key part of security in a threat model where (for example) an hostile state actor wants to surveil your communications and can seize your devices. On IRC, servers don't actually keep messages all that long: they pass them along to other servers and clients as fast as they can, only keep them in memory, and move on to the next message. There are no concerns about data retention on messages (and their metadata) other than the network layer. (I'm ignoring the issues with user registration, which is a separate, if valid, concern.) Obviously, an hostile server could log everything passing through it, but IRC federations are normally tightly controlled. So, if you trust your IRC operators, you should be fairly safe. Obviously, clients can (and often do, even if OTR is configured!) log all messages, but this is generally not the default. Irssi, for example, does not log by default. IRC bouncers are more likely to log to disk, of course, to be able to do what they do. Compare this to Matrix: when you send a message to a Matrix homeserver, that server first stores it in its internal SQL database. Then it will transmit that message to all clients connected to that server and room, and to all other servers that have clients connected to that room. Those remote servers, in turn, will keep a copy of that message and all its metadata in their own database, by default forever. On encrypted rooms those messages are encrypted, but not their metadata. There is a mechanism to expire entries in Synapse, but it is not enabled by default. So one should generally assume that a message sent on Matrix is never expired.

GDPR in the federation But even if that setting was enabled by default, how do you control it? This is a fundamental problem of the federation: if any user is allowed to join a room (which is the default), those user's servers will log all content and metadata from that room. That includes private, one-on-one conversations, since those are essentially rooms as well. In the context of the GDPR, this is really tricky: who is the responsible party (known as the "data controller") here? It's basically any yahoo who fires up a home server and joins a room. In a federated network, one has to wonder whether GDPR enforcement is even possible at all. But in Matrix in particular, if you want to enforce your right to be forgotten in a given room, you would have to:
  1. enumerate all the users that ever joined the room while you were there
  2. discover all their home servers
  3. start a GDPR procedure against all those servers
I recognize this is a hard problem to solve while still keeping an open ecosystem. But I believe that Matrix should have much stricter defaults towards data retention than right now. Message expiry should be enforced by default, for example. (Note that there are also redaction policies that could be used to implement part of the GDPR automatically, see the privacy policy discussion below on that.) Also keep in mind that, in the brave new peer-to-peer world that Matrix is heading towards, the boundary between server and client is likely to be fuzzier, which would make applying the GDPR even more difficult. Update: this comment links to this post (in german) which apparently studied the question and concluded that Matrix is not GDPR-compliant. In fact, maybe Synapse should be designed so that there's no configurable flag to turn off data retention. A bit like how most system loggers in UNIX (e.g. syslog) come with a log retention system that typically rotate logs after a few weeks or month. Historically, this was designed to keep hard drives from filling up, but it also has the added benefit of limiting the amount of personal information kept on disk in this modern day. (Arguably, syslog doesn't rotate logs on its own, but, say, Debian GNU/Linux, as an installed system, does have log retention policies well defined for installed packages, and those can be discussed. And "no expiry" is definitely a bug.

Matrix.org privacy policy When I first looked at Matrix, five years ago, Element.io was called Riot.im and had a rather dubious privacy policy:
We currently use cookies to support our use of Google Analytics on the Website and Service. Google Analytics collects information about how you use the Website and Service. [...] This helps us to provide you with a good experience when you browse our Website and use our Service and also allows us to improve our Website and our Service.
When I asked Matrix people about why they were using Google Analytics, they explained this was for development purposes and they were aiming for velocity at the time, not privacy (paraphrasing here). They also included a "free to snitch" clause:
If we are or believe that we are under a duty to disclose or share your personal data, we will do so in order to comply with any legal obligation, the instructions or requests of a governmental authority or regulator, including those outside of the UK.
Those are really broad terms, above and beyond what is typically expected legally. Like the current retention policies, such user tracking and ... "liberal" collaboration practices with the state set a bad precedent for other home servers. Thankfully, since the above policy was published (2017), the GDPR was "implemented" (2018) and it seems like both the Element.io privacy policy and the Matrix.org privacy policy have been somewhat improved since. Notable points of the new privacy policies:
  • 2.3.1.1: the "federation" section actually outlines that "Federated homeservers and Matrix clients which respect the Matrix protocol are expected to honour these controls and redaction/erasure requests, but other federated homeservers are outside of the span of control of Element, and we cannot guarantee how this data will be processed"
  • 2.6: users under the age of 16 should not use the matrix.org service
  • 2.10: Upcloud, Mythic Beast, Amazon, and CloudFlare possibly have access to your data (it's nice to at least mention this in the privacy policy: many providers don't even bother admitting to this kind of delegation)
  • Element 2.2.1: mentions many more third parties (Twilio, Stripe, Quaderno, LinkedIn, Twitter, Google, Outplay, PipeDrive, HubSpot, Posthog, Sentry, and Matomo (phew!) used when you are paying Matrix.org for hosting
I'm not super happy with all the trackers they have on the Element platform, but then again you don't have to use that service. Your favorite homeserver (assuming you are not on Matrix.org) probably has their own Element deployment, hopefully without all that garbage. Overall, this is all a huge improvement over the previous privacy policy, so hats off to the Matrix people for figuring out a reasonable policy in such a tricky context. I particularly like this bit:
We will forget your copy of your data upon your request. We will also forward your request to be forgotten onto federated homeservers. However - these homeservers are outside our span of control, so we cannot guarantee they will forget your data.
It's great they implemented those mechanisms and, after all, if there's an hostile party in there, nothing can prevent them from using screenshots to just exfiltrate your data away from the client side anyways, even with services typically seen as more secure, like Signal. As an aside, I also appreciate that Matrix.org has a fairly decent code of conduct, based on the TODO CoC which checks all the boxes in the geekfeminism wiki.

Metadata handling Overall, privacy protections in Matrix mostly concern message contents, not metadata. In other words, who's talking with who, when and from where is not well protected. Compared to a tool like Signal, which goes through great lengths to anonymize that data with features like private contact discovery, disappearing messages, sealed senders, and private groups, Matrix is definitely behind. (Note: there is an issue open about message lifetimes in Element since 2020, but it's not at even at the MSC stage yet.) This is a known issue (opened in 2019) in Synapse, but this is not just an implementation issue, it's a flaw in the protocol itself. Home servers keep join/leave of all rooms, which gives clear text information about who is talking to. Synapse logs may also contain privately identifiable information that home server admins might not be aware of in the first place. Those log rotation policies are separate from the server-level retention policy, which may be confusing for a novice sysadmin. Combine this with the federation: even if you trust your home server to do the right thing, the second you join a public room with third-party home servers, those ideas kind of get thrown out because those servers can do whatever they want with that information. Again, a problem that is hard to solve in any federation. To be fair, IRC doesn't have a great story here either: any client knows not only who's talking to who in a room, but also typically their client IP address. Servers can (and often do) obfuscate this, but often that obfuscation is trivial to reverse. Some servers do provide "cloaks" (sometimes automatically), but that's kind of a "slap-on" solution that actually moves the problem elsewhere: now the server knows a little more about the user. Overall, I would worry much more about a Matrix home server seizure than a IRC or Signal server seizure. Signal does get subpoenas, and they can only give out a tiny bit of information about their users: their phone number, and their registration, and last connection date. Matrix carries a lot more information in its database.

Amplification attacks on URL previews I (still!) run an Icecast server and sometimes share links to it on IRC which, obviously, also ends up on (more than one!) Matrix home servers because some people connect to IRC using Matrix. This, in turn, means that Matrix will connect to that URL to generate a link preview. I feel this outlines a security issue, especially because those sockets would be kept open seemingly forever. I tried to warn the Matrix security team but somehow, I don't think this issue was taken very seriously. Here's the disclosure timeline:
  • January 18: contacted Matrix security
  • January 19: response: already reported as a bug
  • January 20: response: can't reproduce
  • January 31: timeout added, considered solved
  • January 31: I respond that I believe the security issue is underestimated, ask for clearance to disclose
  • February 1: response: asking for two weeks delay after the next release (1.53.0) including another patch, presumably in two weeks' time
  • February 22: Matrix 1.53.0 released
  • April 14: I notice the release, ask for clearance again
  • April 14: response: referred to the public disclosure
There are a couple of problems here:
  1. the bug was publicly disclosed in September 2020, and not considered a security issue until I notified them, and even then, I had to insist
  2. no clear disclosure policy timeline was proposed or seems established in the project (there is a security disclosure policy but it doesn't include any predefined timeline)
  3. I wasn't informed of the disclosure
  4. the actual solution is a size limit (10MB, already implemented), a time limit (30 seconds, implemented in PR 11784), and a content type allow list (HTML, "media" or JSON, implemented in PR 11936), and I'm not sure it's adequate
  5. (pure vanity:) I did not make it to their Hall of fame
I'm not sure those solutions are adequate because they all seem to assume a single home server will pull that one URL for a little while then stop. But in a federated network, many (possibly thousands) home servers may be connected in a single room at once. If an attacker drops a link into such a room, all those servers would connect to that link all at once. This is an amplification attack: a small amount of traffic will generate a lot more traffic to a single target. It doesn't matter there are size or time limits: the amplification is what matters here. It should also be noted that clients that generate link previews have more amplification because they are more numerous than servers. And of course, the default Matrix client (Element) does generate link previews as well. That said, this is possibly not a problem specific to Matrix: any federated service that generates link previews may suffer from this. I'm honestly not sure what the solution is here. Maybe moderation? Maybe link previews are just evil? All I know is there was this weird bug in my Icecast server and I tried to ring the bell about it, and it feels it was swept under the rug. Somehow I feel this is bound to blow up again in the future, even with the current mitigation.

Moderation In Matrix like elsewhere, Moderation is a hard problem. There is a detailed moderation guide and much of this problem space is actively worked on in Matrix right now. A fundamental problem with moderating a federated space is that a user banned from a room can rejoin the room from another server. This is why spam is such a problem in Email, and why IRC networks have stopped federating ages ago (see the IRC history for that fascinating story).

The mjolnir bot The mjolnir moderation bot is designed to help with some of those things. It can kick and ban users, redact all of a user's message (as opposed to one by one), all of this across multiple rooms. It can also subscribe to a federated block list published by matrix.org to block known abusers (users or servers). Bans are pretty flexible and can operate at the user, room, or server level. Matrix people suggest making the bot admin of your channels, because you can't take back admin from a user once given.

The command-line tool There's also a new command line tool designed to do things like:
  • System notify users (all users/users from a list, specific user)
  • delete sessions/devices not seen for X days
  • purge the remote media cache
  • select rooms with various criteria (external/local/empty/created by/encrypted/cleartext)
  • purge history of theses rooms
  • shutdown rooms
This tool and Mjolnir are based on the admin API built into Synapse.

Rate limiting Synapse has pretty good built-in rate-limiting which blocks repeated login, registration, joining, or messaging attempts. It may also end up throttling servers on the federation based on those settings.

Fundamental federation problems Because users joining a room may come from another server, room moderators are at the mercy of the registration and moderation policies of those servers. Matrix is like IRC's +R mode ("only registered users can join") by default, except that anyone can register their own homeserver, which makes this limited. Server admins can block IP addresses and home servers, but those tools are not easily available to room admins. There is an API (m.room.server_acl in /devtools) but it is not reliable (thanks Austin Huang for the clarification). Matrix has the concept of guest accounts, but it is not used very much, and virtually no client or homeserver supports it. This contrasts with the way IRC works: by default, anyone can join an IRC network even without authentication. Some channels require registration, but in general you are free to join and look around (until you get blocked, of course). I have seen anecdotal evidence (CW: Twitter, nitter link) that "moderating bridges is hell", and I can imagine why. Moderation is already hard enough on one federation, when you bridge a room with another network, you inherit all the problems from that network but without the entire abuse control tools from the original network's API...

Room admins Matrix, in particular, has the problem that room administrators (which have the power to redact messages, ban users, and promote other users) are bound to their Matrix ID which is, in turn, bound to their home servers. This implies that a home server administrators could (1) impersonate a given user and (2) use that to hijack the room. So in practice, the home server is the trust anchor for rooms, not the user themselves. That said, if server B administrator hijack user joe on server B, they will hijack that room on that specific server. This will not (necessarily) affect users on the other servers, as servers could refuse parts of the updates or ban the compromised account (or server). It does seem like a major flaw that room credentials are bound to Matrix identifiers, as opposed to the E2E encryption credentials. In an encrypted room even with fully verified members, a compromised or hostile home server can still take over the room by impersonating an admin. That admin (or even a newly minted user) can then send events or listen on the conversations. This is even more frustrating when you consider that Matrix events are actually signed and therefore have some authentication attached to them, acting like some sort of Merkle tree (as it contains a link to previous events). That signature, however, is made from the homeserver PKI keys, not the client's E2E keys, which makes E2E feel like it has been "bolted on" later.

Availability While Matrix has a strong advantage over Signal in that it's decentralized (so anyone can run their own homeserver,), I couldn't find an easy way to run a "multi-primary" setup, or even a "redundant" setup (even if with a single primary backend), short of going full-on "replicate PostgreSQL and Redis data", which is not typically for the faint of heart.

How this works in IRC On IRC, it's quite easy to setup redundant nodes. All you need is:
  1. a new machine (with it's own public address with an open port)
  2. a shared secret (or certificate) between that machine and an existing one on the network
  3. a connect block on both servers
That's it: the node will join the network and people can connect to it as usual and share the same user/namespace as the rest of the network. The servers take care of synchronizing state: you do not need to worry about replicating a database server. (Now, experienced IRC people will know there's a catch here: IRC doesn't have authentication built in, and relies on "services" which are basically bots that authenticate users (I'm simplifying, don't nitpick). If that service goes down, the network still works, but then people can't authenticate, and they can start doing nasty things like steal people's identity if they get knocked offline. But still: basic functionality still works: you can talk in rooms and with users that are on the reachable network.)

User identities Matrix is more complicated. Each "home server" has its own identity namespace: a specific user (say @anarcat:matrix.org) is bound to that specific home server. If that server goes down, that user is completely disconnected. They could register a new account elsewhere and reconnect, but then they basically lose all their configuration: contacts, joined channels are all lost. (Also notice how the Matrix IDs don't look like a typical user address like an email in XMPP. They at least did their homework and got the allocation for the scheme.)

Rooms Users talk to each other in "rooms", even in one-to-one communications. (Rooms are also used for other things like "spaces", they're basically used for everything, think "everything is a file" kind of tool.) For rooms, home servers act more like IRC nodes in that they keep a local state of the chat room and synchronize it with other servers. Users can keep talking inside a room if the server that originally hosts the room goes down. Rooms can have a local, server-specific "alias" so that, say, #room:matrix.org is also visible as #room:example.com on the example.com home server. Both addresses refer to the same room underlying room. (Finding this in the Element settings is not obvious though, because that "alias" are actually called a "local address" there. So to create such an alias (in Element), you need to go in the room settings' "General" section, "Show more" in "Local address", then add the alias name (e.g. foo), and then that room will be available on your example.com homeserver as #foo:example.com.) So a room doesn't belong to a server, it belongs to the federation, and anyone can join the room from any serer (if the room is public, or if invited otherwise). You can create a room on server A and when a user from server B joins, the room will be replicated on server B as well. If server A fails, server B will keep relaying traffic to connected users and servers. A room is therefore not fundamentally addressed with the above alias, instead ,it has a internal Matrix ID, which basically a random string. It has a server name attached to it, but that was made just to avoid collisions. That can get a little confusing. For example, the #fractal:gnome.org room is an alias on the gnome.org server, but the room ID is !hwiGbsdSTZIwSRfybq:matrix.org. That's because the room was created on matrix.org, but the preferred branding is gnome.org now. As an aside, rooms, by default, live forever, even after the last user quits. There's an admin API to delete rooms and a tombstone event to redirect to another one, but neither have a GUI yet. The latter is part of MSC1501 ("Room version upgrades") which allows a room admin to close a room, with a message and a pointer to another room.

Spaces Discovering rooms can be tricky: there is a per-server room directory, but Matrix.org people are trying to deprecate it in favor of "Spaces". Room directories were ripe for abuse: anyone can create a room, so anyone can show up in there. It's possible to restrict who can add aliases, but anyways directories were seen as too limited. In contrast, a "Space" is basically a room that's an index of other rooms (including other spaces), so existing moderation and administration mechanism that work in rooms can (somewhat) work in spaces as well. This enables a room directory that works across federation, regardless on which server they were originally created. New users can be added to a space or room automatically in Synapse. (Existing users can be told about the space with a server notice.) This gives admins a way to pre-populate a list of rooms on a server, which is useful to build clusters of related home servers, providing some sort of redundancy, at the room -- not user -- level.

Home servers So while you can workaround a home server going down at the room level, there's no such thing at the home server level, for user identities. So if you want those identities to be stable in the long term, you need to think about high availability. One limitation is that the domain name (e.g. matrix.example.com) must never change in the future, as renaming home servers is not supported. The documentation used to say you could "run a hot spare" but that has been removed. Last I heard, it was not possible to run a high-availability setup where multiple, separate locations could replace each other automatically. You can have high performance setups where the load gets distributed among workers, but those are based on a shared database (Redis and PostgreSQL) backend. So my guess is it would be possible to create a "warm" spare server of a matrix home server with regular PostgreSQL replication, but that is not documented in the Synapse manual. This sort of setup would also not be useful to deal with networking issues or denial of service attacks, as you will not be able to spread the load over multiple network locations easily. Redis and PostgreSQL heroes are welcome to provide their multi-primary solution in the comments. In the meantime, I'll just point out this is a solution that's handled somewhat more gracefully in IRC, by having the possibility of delegating the authentication layer.

Delegations If you do not want to run a Matrix server yourself, it's possible to delegate the entire thing to another server. There's a server discovery API which uses the .well-known pattern (or SRV records, but that's "not recommended" and a bit confusing) to delegate that service to another server. Be warned that the server still needs to be explicitly configured for your domain. You can't just put:
  "m.server": "matrix.org:443"  
... on https://example.com/.well-known/matrix/server and start using @you:example.com as a Matrix ID. That's because Matrix doesn't support "virtual hosting" and you'd still be connecting to rooms and people with your matrix.org identity, not example.com as you would normally expect. This is also why you cannot rename your home server. The server discovery API is what allows servers to find each other. Clients, on the other hand, use the client-server discovery API: this is what allows a given client to find your home server when you type your Matrix ID on login.

Performance The high availability discussion brushed over the performance of Matrix itself, but let's now dig into that.

Horizontal scalability There were serious scalability issues of the main Matrix server, Synapse, in the past. So the Matrix team has been working hard to improve its design. Since Synapse 1.22 the home server can horizontally scale to multiple workers (see this blog post for details) which can make it easier to scale large servers.

Other implementations There are other promising home servers implementations from a performance standpoint (dendrite, Golang, entered beta in late 2020; conduit, Rust, beta; others), but none of those are feature-complete so there's a trade-off to be made there. Synapse is also adding a lot of feature fast, so it's an open question whether the others will ever catch up. (I have heard that Dendrite might actually surpass Synapse in features within a few years, which would put Synapse in a more "LTS" situation.)

Latency Matrix can feel slow sometimes. For example, joining the "Matrix HQ" room in Element (from matrix.debian.social) takes a few minutes and then fails. That is because the home server has to sync the entire room state when you join the room. There was promising work on this announced in the lengthy 2021 retrospective, and some of that work landed (partial sync) in the 1.53 release already. Other improvements coming include sliding sync, lazy loading over federation, and fast room joins. So that's actually something that could be fixed in the fairly short term. But in general, communication in Matrix doesn't feel as "snappy" as on IRC or even Signal. It's hard to quantify this without instrumenting a full latency test bed (for example the tools I used in the terminal emulators latency tests), but even just typing in a web browser feels slower than typing in a xterm or Emacs for me. Even in conversations, I "feel" people don't immediately respond as fast. In fact, this could be an interesting double-blind experiment to make: have people guess whether they are talking to a person on Matrix, XMPP, or IRC, for example. My theory would be that people could notice that Matrix users are slower, if only because of the TCP round-trip time each message has to take.

Transport Some courageous person actually made some tests of various messaging platforms on a congested network. His evaluation was basically:
  • Briar: uses Tor, so unusable except locally
  • Matrix: "struggled to send and receive messages", joining a room takes forever as it has to sync all history, "took 20-30 seconds for my messages to be sent and another 20 seconds for further responses"
  • XMPP: "worked in real-time, full encryption, with nearly zero lag"
So that was interesting. I suspect IRC would have also fared better, but that's just a feeling. Other improvements to the transport layer include support for websocket and the CoAP proxy work from 2019 (targeting 100bps links), but both seem stalled at the time of writing. The Matrix people have also announced the pinecone p2p overlay network which aims at solving large, internet-scale routing problems. See also this talk at FOSDEM 2022.

Usability

Onboarding and workflow The workflow for joining a room, when you use Element web, is not great:
  1. click on a link in a web browser
  2. land on (say) https://matrix.to/#/#matrix-dev:matrix.org
  3. offers "Element", yeah that's sounds great, let's click "Continue"
  4. land on https://app.element.io/#/room%2F%23matrix-dev%3Amatrix.org and then you need to register, aaargh
As you might have guessed by now, there is a specification to solve this, but web browsers need to adopt it as well, so that's far from actually being solved. At least browsers generally know about the matrix: scheme, it's just not exactly clear what they should do with it, especially when the handler is just another web page (e.g. Element web). In general, when compared with tools like Signal or WhatsApp, Matrix doesn't fare so well in terms of user discovery. I probably have some of my normal contacts that have a Matrix account as well, but there's really no way to know. It's kind of creepy when Signal tells you "this person is on Signal!" but it's also pretty cool that it works, and they actually implemented it pretty well. Registration is also less obvious: in Signal, the app confirms your phone number automatically. It's friction-less and quick. In Matrix, you need to learn about home servers, pick one, register (with a password! aargh!), and then setup encryption keys (not default), etc. It's a lot more friction. And look, I understand: giving away your phone number is a huge trade-off. I don't like it either. But it solves a real problem and makes encryption accessible to a ton more people. Matrix does have "identity servers" that can serve that purpose, but I don't feel confident sharing my phone number there. It doesn't help that the identity servers don't have private contact discovery: giving them your phone number is a more serious security compromise than with Signal. There's a catch-22 here too: because no one feels like giving away their phone numbers, no one does, and everyone assumes that stuff doesn't work anyways. Like it or not, Signal forcing people to divulge their phone number actually gives them critical mass that means actually a lot of my relatives are on Signal and I don't have to install crap like WhatsApp to talk with them.

5 minute clients evaluation Throughout all my tests I evaluated a handful of Matrix clients, mostly from Flathub because almost none of them are packaged in Debian. Right now I'm using Element, the flagship client from Matrix.org, in a web browser window, with the PopUp Window extension. This makes it look almost like a native app, and opens links in my main browser window (instead of a new tab in that separate window), which is nice. But I'm tired of buying memory to feed my web browser, so this indirection has to stop. Furthermore, I'm often getting completely logged off from Element, which means re-logging in, recovering my security keys, and reconfiguring my settings. That is extremely annoying. Coming from Irssi, Element is really "GUI-y" (pronounced "gooey"). Lots of clickety happening. To mark conversations as read, in particular, I need to click-click-click on all the tabs that have some activity. There's no "jump to latest message" or "mark all as read" functionality as far as I could tell. In Irssi the former is built-in (alt-a) and I made a custom /READ command for the latter:
/ALIAS READ script exec \$_->activity(0) for Irssi::windows
And yes, that's a Perl script in my IRC client. I am not aware of any Matrix client that does stuff like that, except maybe Weechat, if we can call it a Matrix client, or Irssi itself, now that it has a Matrix plugin (!). As for other clients, I have looked through the Matrix Client Matrix (confusing right?) to try to figure out which one to try, and, even after selecting Linux as a filter, the chart is just too wide to figure out anything. So I tried those, kind of randomly:
  • Fractal
  • Mirage
  • Nheko
  • Quaternion
Unfortunately, I lost my notes on those, I don't actually remember which one did what. I still have a session open with Mirage, so I guess that means it's the one I preferred, but I remember they were also all very GUI-y. Maybe I need to look at weechat-matrix or gomuks. At least Weechat is scriptable so I could continue playing the power-user. Right now my strategy with messaging (and that includes microblogging like Twitter or Mastodon) is that everything goes through my IRC client, so Weechat could actually fit well in there. Going with gomuks, on the other hand, would mean running it in parallel with Irssi or ... ditching IRC, which is a leap I'm not quite ready to take just yet. Oh, and basically none of those clients (except Nheko and Element) support VoIP, which is still kind of a second-class citizen in Matrix. It does not support large multimedia rooms, for example: Jitsi was used for FOSDEM instead of the native videoconferencing system.

Bots This falls a little aside the "usability" section, but I didn't know where to put this... There's a few Matrix bots out there, and you are likely going to be able to replace your existing bots with Matrix bots. It's true that IRC has a long and impressive history with lots of various bots doing various things, but given how young Matrix is, there's still a good variety:
  • maubot: generic bot with tons of usual plugins like sed, dice, karma, xkcd, echo, rss, reminder, translate, react, exec, gitlab/github webhook receivers, weather, etc
  • opsdroid: framework to implement "chat ops" in Matrix, connects with Matrix, GitHub, GitLab, Shell commands, Slack, etc
  • matrix-nio: another framework, used to build lots more bots like:
    • hemppa: generic bot with various functionality like weather, RSS feeds, calendars, cron jobs, OpenStreetmaps lookups, URL title snarfing, wolfram alpha, astronomy pic of the day, Mastodon bridge, room bridging, oh dear
    • devops: ping, curl, etc
    • podbot: play podcast episodes from AntennaPod
    • cody: Python, Ruby, Javascript REPL
    • eno: generic bot, "personal assistant"
  • mjolnir: moderation bot
  • hookshot: bridge with GitLab/GitHub
  • matrix-monitor-bot: latency monitor
One thing I haven't found an equivalent for is Debian's MeetBot. There's an archive bot but it doesn't have topics or a meeting chair, or HTML logs.

Working on Matrix As a developer, I find Matrix kind of intimidating. The specification is huge. The official specification itself looks somewhat digestable: it's only 6 APIs so that looks, at first, kind of reasonable. But whenever you start asking complicated questions about Matrix, you quickly fall into the Matrix Spec Change specification (which, yes, is a separate specification). And there are literally hundreds of MSCs flying around. It's hard to tell what's been adopted and what hasn't, and even harder to figure out if your specific client has implemented it. (One trendy answer to this problem is to "rewrite it in rust": Matrix are working on implementing a lot of those specifications in a matrix-rust-sdk that's designed to take the implementation details away from users.) Just taking the latest weekly Matrix report, you find that three new MSCs proposed, just last week! There's even a graph that shows the number of MSCs is progressing steadily, at 600+ proposals total, with the majority (300+) "new". I would guess the "merged" ones are at about 150. That's a lot of text which includes stuff like 3D worlds which, frankly, I don't think you should be working on when you have such important security and usability problems. (The internet as a whole, arguably, doesn't fare much better. RFC600 is a really obscure discussion about "INTERFACING AN ILLINOIS PLASMA TERMINAL TO THE ARPANET". Maybe that's how many MSCs will end up as well, left forgotten in the pits of history.) And that's the thing: maybe the Matrix people have a different objective than I have. They want to connect everything to everything, and make Matrix a generic transport for all sorts of applications, including virtual reality, collaborative editors, and so on. I just want secure, simple messaging. Possibly with good file transfers, and video calls. That it works with existing stuff is good, and it should be federated to remove the "Signal point of failure". So I'm a bit worried with the direction all those MSCs are taking, especially when you consider that clients other than Element are still struggling to keep up with basic features like end-to-end encryption or room discovery, never mind voice or spaces...

Conclusion Overall, Matrix is somehow in the space XMPP was a few years ago. It has a ton of features, pretty good clients, and a large community. It seems to have gained some of the momentum that XMPP has lost. It may have the most potential to replace Signal if something bad would happen to it (like, I don't know, getting banned or going nuts with cryptocurrency)... But it's really not there yet, and I don't see Matrix trying to get there either, which is a bit worrisome.

Looking back at history I'm also worried that we are repeating the errors of the past. The history of federated services is really fascinating:. IRC, FTP, HTTP, and SMTP were all created in the early days of the internet, and are all still around (except, arguably, FTP, which was removed from major browsers recently). All of them had to face serious challenges in growing their federation. IRC had numerous conflicts and forks, both at the technical level but also at the political level. The history of IRC is really something that anyone working on a federated system should study in detail, because they are bound to make the same mistakes if they are not familiar with it. The "short" version is:
  • 1988: Finnish researcher publishes first IRC source code
  • 1989: 40 servers worldwide, mostly universities
  • 1990: EFnet ("eris-free network") fork which blocks the "open relay", named Eris - followers of Eris form the A-net, which promptly dissolves itself, with only EFnet remaining
  • 1992: Undernet fork, which offered authentication ("services"), routing improvements and timestamp-based channel synchronisation
  • 1994: DALnet fork, from Undernet, again on a technical disagreement
  • 1995: Freenode founded
  • 1996: IRCnet forks from EFnet, following a flame war of historical proportion, splitting the network between Europe and the Americas
  • 1997: Quakenet founded
  • 1999: (XMPP founded)
  • 2001: 6 million users, OFTC founded
  • 2002: DALnet peaks at 136,000 users
  • 2003: IRC as a whole peaks at 10 million users, EFnet peaks at 141,000 users
  • 2004: (Facebook founded), Undernet peaks at 159,000 users
  • 2005: Quakenet peaks at 242,000 users, IRCnet peaks at 136,000 (Youtube founded)
  • 2006: (Twitter founded)
  • 2009: (WhatsApp, Pinterest founded)
  • 2010: (TextSecure AKA Signal, Instagram founded)
  • 2011: (Snapchat founded)
  • ~2013: Freenode peaks at ~100,000 users
  • 2016: IRCv3 standardisation effort started (TikTok founded)
  • 2021: Freenode self-destructs, Libera chat founded
  • 2022: Libera peaks at 50,000 users, OFTC peaks at 30,000 users
(The numbers were taken from the Wikipedia page and Netsplit.de. Note that I also include other networks launch in parenthesis for context.) Pretty dramatic, don't you think? Eventually, somehow, IRC became irrelevant for most people: few people are even aware of it now. With less than a million users active, it's smaller than Mastodon, XMPP, or Matrix at this point.1 If I were to venture a guess, I'd say that infighting, lack of a standardization body, and a somewhat annoying protocol meant the network could not grow. It's also possible that the decentralised yet centralised structure of IRC networks limited their reliability and growth. But large social media companies have also taken over the space: observe how IRC numbers peak around the time the wave of large social media companies emerge, especially Facebook (2.9B users!!) and Twitter (400M users).

Where the federated services are in history Right now, Matrix, and Mastodon (and email!) are at the "pre-EFnet" stage: anyone can join the federation. Mastodon has started working on a global block list of fascist servers which is interesting, but it's still an open federation. Right now, Matrix is totally open, but matrix.org publishes a (federated) block list of hostile servers (#matrix-org-coc-bl:matrix.org, yes, of course it's a room). Interestingly, Email is also in that stage, where there are block lists of spammers, and it's a race between those blockers and spammers. Large email providers, obviously, are getting closer to the EFnet stage: you could consider they only accept email from themselves or between themselves. It's getting increasingly hard to deliver mail to Outlook and Gmail for example, partly because of bias against small providers, but also because they are including more and more machine-learning tools to sort through email and those systems are, fundamentally, unknowable. It's not quite the same as splitting the federation the way EFnet did, but the effect is similar. HTTP has somehow managed to live in a parallel universe, as it's technically still completely federated: anyone can start a web server if they have a public IP address and anyone can connect to it. The catch, of course, is how you find the darn thing. Which is how Google became one of the most powerful corporations on earth, and how they became the gatekeepers of human knowledge online. I have only briefly mentioned XMPP here, and my XMPP fans will undoubtedly comment on that, but I think it's somewhere in the middle of all of this. It was co-opted by Facebook and Google, and both corporations have abandoned it to its fate. I remember fondly the days where I could do instant messaging with my contacts who had a Gmail account. Those days are gone, and I don't talk to anyone over Jabber anymore, unfortunately. And this is a threat that Matrix still has to face. It's also the threat Email is currently facing. On the one hand corporations like Facebook want to completely destroy it and have mostly succeeded: many people just have an email account to register on things and talk to their friends over Instagram or (lately) TikTok (which, I know, is not Facebook, but they started that fire). On the other hand, you have corporations like Microsoft and Google who are still using and providing email services because, frankly, you still do need email for stuff, just like fax is still around but they are more and more isolated in their own silo. At this point, it's only a matter of time they reach critical mass and just decide that the risk of allowing external mail coming in is not worth the cost. They'll simply flip the switch and work on an allow-list principle. Then we'll have closed the loop and email will be dead, just like IRC is "dead" now. I wonder which path Matrix will take. Could it liberate us from these vicious cycles? Update: this generated some discussions on lobste.rs.

  1. According to Wikipedia, there are currently about 500 distinct IRC networks operating, on about 1,000 servers, serving over 250,000 users. In contrast, Mastodon seems to be around 5 million users, Matrix.org claimed at FOSDEM 2021 to have about 28 million globally visible accounts, and Signal lays claim to over 40 million souls. XMPP claims to have "millions" of users on the xmpp.org homepage but the FAQ says they don't actually know. On the proprietary silo side of the fence, this page says
    • Facebook: 2.9 billion users
    • WhatsApp: 2B
    • Instagram: 1.4B
    • TikTok: 1B
    • Snapchat: 500M
    • Pinterest: 480M
    • Twitter: 397M
    Notable omission from that list: Youtube, with its mind-boggling 2.6 billion users... Those are not the kind of numbers you just "need to convince a brother or sister" to grow the network...

26 May 2022

Sergio Talens-Oliag: New Blog Config

As promised, on this post I m going to explain how I ve configured this blog using hugo, asciidoctor and the papermod theme, how I publish it using nginx, how I ve integrated the remark42 comment system and how I ve automated its publication using gitea and json2file-go. It is a long post, but I hope that at least parts of it can be interesting for some, feel free to ignore it if that is not your case

Hugo Configuration

Theme settingsThe site is using the PaperMod theme and as I m using asciidoctor to publish my content I ve adjusted the settings to improve how things are shown with it. The current config.yml file is the one shown below (probably some of the settings are not required nor being used right now, but I m including the current file, so this post will have always the latest version of it):
config.yml
baseURL: https://blogops.mixinet.net/
title: Mixinet BlogOps
paginate: 5
theme: PaperMod
destination: public/
enableInlineShortcodes: true
enableRobotsTXT: true
buildDrafts: false
buildFuture: false
buildExpired: false
enableEmoji: true
pygmentsUseClasses: true
minify:
  disableXML: true
  minifyOutput: true
languages:
  en:
    languageName: "English"
    description: "Mixinet BlogOps - https://blogops.mixinet.net/"
    author: "Sergio Talens-Oliag"
    weight: 1
    title: Mixinet BlogOps
    homeInfoParams:
      Title: "Sergio Talens-Oliag Technical Blog"
      Content: >
        ![Mixinet BlogOps](/images/mixinet-blogops.png)
    taxonomies:
      category: categories
      tag: tags
      series: series
    menu:
      main:
        - name: Archive
          url: archives
          weight: 5
        - name: Categories
          url: categories/
          weight: 10
        - name: Tags
          url: tags/
          weight: 10
        - name: Search
          url: search/
          weight: 15
outputs:
  home:
    - HTML
    - RSS
    - JSON
params:
  env: production
  defaultTheme: light
  disableThemeToggle: false
  ShowShareButtons: true
  ShowReadingTime: true
  disableSpecial1stPost: true
  disableHLJS: true
  displayFullLangName: true
  ShowPostNavLinks: true
  ShowBreadCrumbs: true
  ShowCodeCopyButtons: true
  ShowRssButtonInSectionTermList: true
  ShowFullTextinRSS: true
  ShowToc: true
  TocOpen: false
  comments: true
  remark42SiteID: "blogops"
  remark42Url: "/remark42"
  profileMode:
    enabled: false
    title: Sergio Talens-Oliag Technical Blog
    imageUrl: "/images/mixinet-blogops.png"
    imageTitle: Mixinet BlogOps
    buttons:
      - name: Archives
        url: archives
      - name: Categories
        url: categories
      - name: Tags
        url: tags
  socialIcons:
    - name: CV
      url: "https://www.uv.es/~sto/cv/"
    - name: Debian
      url: "https://people.debian.org/~sto/"
    - name: GitHub
      url: "https://github.com/sto/"
    - name: GitLab
      url: "https://gitlab.com/stalens/"
    - name: Linkedin
      url: "https://www.linkedin.com/in/sergio-talens-oliag/"
    - name: RSS
      url: "index.xml"
  assets:
    disableHLJS: true
    favicon: "/favicon.ico"
    favicon16x16:  "/favicon-16x16.png"
    favicon32x32:  "/favicon-32x32.png"
    apple_touch_icon:  "/apple-touch-icon.png"
    safari_pinned_tab:  "/safari-pinned-tab.svg"
  fuseOpts:
    isCaseSensitive: false
    shouldSort: true
    location: 0
    distance: 1000
    threshold: 0.4
    minMatchCharLength: 0
    keys: ["title", "permalink", "summary", "content"]
markup:
  asciidocExt:
    attributes:  
    backend: html5s
    extensions: ['asciidoctor-html5s','asciidoctor-diagram']
    failureLevel: fatal
    noHeaderOrFooter: true
    preserveTOC: false
    safeMode: unsafe
    sectionNumbers: false
    trace: false
    verbose: false
    workingFolderCurrent: true
privacy:
  vimeo:
    disabled: false
    simple: true
  twitter:
    disabled: false
    enableDNT: true
    simple: true
  instagram:
    disabled: false
    simple: true
  youtube:
    disabled: false
    privacyEnhanced: true
services:
  instagram:
    disableInlineCSS: true
  twitter:
    disableInlineCSS: true
security:
  exec:
    allow:
      - '^asciidoctor$'
      - '^dart-sass-embedded$'
      - '^go$'
      - '^npx$'
      - '^postcss$'
Some notes about the settings:
  • disableHLJS and assets.disableHLJS are set to true; we plan to use rouge on adoc and the inclusion of the hljs assets adds styles that collide with the ones used by rouge.
  • ShowToc is set to true and the TocOpen setting is set to false to make the ToC appear collapsed initially. My plan was to use the asciidoctor ToC, but after trying I believe that the theme one looks nice and I don t need to adjust styles, although it has some issues with the html5s processor (the admonition titles use <h6> and they are shown on the ToC, which is weird), to fix it I ve copied the layouts/partial/toc.html to my site repository and replaced the range of headings to end at 5 instead of 6 (in fact 5 still seems a lot, but as I don t think I ll use that heading level on the posts it doesn t really matter).
  • params.profileMode values are adjusted, but for now I ve left it disabled setting params.profileMode.enabled to false and I ve set the homeInfoParams to show more or less the same content with the latest posts under it (I ve added some styles to my custom.css style sheet to center the text and image of the first post to match the look and feel of the profile).
  • On the asciidocExt section I ve adjusted the backend to use html5s, I ve added the asciidoctor-html5s and asciidoctor-diagram extensions to asciidoctor and adjusted the workingFolderCurrent to true to make asciidoctor-diagram work right (haven t tested it yet).

Theme customisationsTo write in asciidoctor using the html5s processor I ve added some files to the assets/css/extended directory:
  1. As said before, I ve added the file assets/css/extended/custom.css to make the homeInfoParams look like the profile page and I ve also changed a little bit some theme styles to make things look better with the html5s output:
    custom.css
    /* Fix first entry alignment to make it look like the profile */
    .first-entry   text-align: center;  
    .first-entry img   display: inline;  
    /**
     * Remove margin for .post-content code and reduce padding to make it look
     * better with the asciidoctor html5s output.
     **/
    .post-content code   margin: auto 0; padding: 4px;  
  2. I ve also added the file assets/css/extended/adoc.css with some styles taken from the asciidoctor-default.css, see this blog post about the original file; mine is the same after formatting it with css-beautify and editing it to use variables for the colors to support light and dark themes:
    adoc.css
    /* AsciiDoctor*/
    table  
        border-collapse: collapse;
        border-spacing: 0
     
    .admonitionblock>table  
        border-collapse: separate;
        border: 0;
        background: none;
        width: 100%
     
    .admonitionblock>table td.icon  
        text-align: center;
        width: 80px
     
    .admonitionblock>table td.icon img  
        max-width: none
     
    .admonitionblock>table td.icon .title  
        font-weight: bold;
        font-family: "Open Sans", "DejaVu Sans", sans-serif;
        text-transform: uppercase
     
    .admonitionblock>table td.content  
        padding-left: 1.125em;
        padding-right: 1.25em;
        border-left: 1px solid #ddddd8;
        color: var(--primary)
     
    .admonitionblock>table td.content>:last-child>:last-child  
        margin-bottom: 0
     
    .admonitionblock td.icon [class^="fa icon-"]  
        font-size: 2.5em;
        text-shadow: 1px 1px 2px var(--secondary);
        cursor: default
     
    .admonitionblock td.icon .icon-note::before  
        content: "\f05a";
        color: var(--icon-note-color)
     
    .admonitionblock td.icon .icon-tip::before  
        content: "\f0eb";
        color: var(--icon-tip-color)
     
    .admonitionblock td.icon .icon-warning::before  
        content: "\f071";
        color: var(--icon-warning-color)
     
    .admonitionblock td.icon .icon-caution::before  
        content: "\f06d";
        color: var(--icon-caution-color)
     
    .admonitionblock td.icon .icon-important::before  
        content: "\f06a";
        color: var(--icon-important-color)
     
    .conum[data-value]  
        display: inline-block;
        color: #fff !important;
        background-color: rgba(100, 100, 0, .8);
        -webkit-border-radius: 100px;
        border-radius: 100px;
        text-align: center;
        font-size: .75em;
        width: 1.67em;
        height: 1.67em;
        line-height: 1.67em;
        font-family: "Open Sans", "DejaVu Sans", sans-serif;
        font-style: normal;
        font-weight: bold
     
    .conum[data-value] *  
        color: #fff !important
     
    .conum[data-value]+b  
        display: none
     
    .conum[data-value]::after  
        content: attr(data-value)
     
    pre .conum[data-value]  
        position: relative;
        top: -.125em
     
    b.conum *  
        color: inherit !important
     
    .conum:not([data-value]):empty  
        display: none
     
  3. The previous file uses variables from a partial copy of the theme-vars.css file that changes the highlighted code background color and adds the color definitions used by the admonitions:
    theme-vars.css
    :root  
        /* Solarized base2 */
        /* --hljs-bg: rgb(238, 232, 213); */
        /* Solarized base3 */
        /* --hljs-bg: rgb(253, 246, 227); */
        /* Solarized base02 */
        --hljs-bg: rgb(7, 54, 66);
        /* Solarized base03 */
        /* --hljs-bg: rgb(0, 43, 54); */
        /* Default asciidoctor theme colors */
        --icon-note-color: #19407c;
        --icon-tip-color: var(--primary);
        --icon-warning-color: #bf6900;
        --icon-caution-color: #bf3400;
        --icon-important-color: #bf0000
     
    .dark  
        --hljs-bg: rgb(7, 54, 66);
        /* Asciidoctor theme colors with tint for dark background */
        --icon-note-color: #3e7bd7;
        --icon-tip-color: var(--primary);
        --icon-warning-color: #ff8d03;
        --icon-caution-color: #ff7847;
        --icon-important-color: #ff3030
     
  4. The previous styles use font-awesome, so I ve downloaded its resources for version 4.7.0 (the one used by asciidoctor) storing the font-awesome.css into on the assets/css/extended dir (that way it is merged with the rest of .css files) and copying the fonts to the static/assets/fonts/ dir (will be served directly):
    FA_BASE_URL="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/4.7.0"
    curl "$FA_BASE_URL/css/font-awesome.css" \
      > assets/css/extended/font-awesome.css
    for f in FontAwesome.otf fontawesome-webfont.eot \
      fontawesome-webfont.svg fontawesome-webfont.ttf \
      fontawesome-webfont.woff fontawesome-webfont.woff2; do
        curl "$FA_BASE_URL/fonts/$f" > "static/assets/fonts/$f"
    done
  5. As already said the default highlighter is disabled (it provided a css compatible with rouge) so we need a css to do the highlight styling; as rouge provides a way to export them, I ve created the assets/css/extended/rouge.css file with the thankful_eyes theme:
    rougify style thankful_eyes > assets/css/extended/rouge.css
  6. To support the use of the html5s backend with admonitions I ve added a variation of the example found on this blog post to assets/js/adoc-admonitions.js:
    adoc-admonitions.js
    // replace the default admonitions block with a table that uses a format
    // similar to the standard asciidoctor ... as we are using fa-icons here there
    // is no need to add the icons: font entry on the document.
    window.addEventListener('load', function ()  
      const admonitions = document.getElementsByClassName('admonition-block')
      for (let i = admonitions.length - 1; i >= 0; i--)  
        const elm = admonitions[i]
        const type = elm.classList[1]
        const title = elm.getElementsByClassName('block-title')[0];
    	const label = title.getElementsByClassName('title-label')[0]
    		.innerHTML.slice(0, -1);
        elm.removeChild(elm.getElementsByClassName('block-title')[0]);
        const text = elm.innerHTML
        const parent = elm.parentNode
        const tempDiv = document.createElement('div')
        tempDiv.innerHTML =  <div class="admonitionblock $ type ">
        <table>
          <tbody>
            <tr>
              <td class="icon">
                <i class="fa icon-$ type " title="$ label "></i>
              </td>
              <td class="content">
                $ text 
              </td>
            </tr>
          </tbody>
        </table>
      </div> 
        const input = tempDiv.childNodes[0]
        parent.replaceChild(input, elm)
       
     )
    and enabled its minified use on the layouts/partials/extend_footer.html file adding the following lines to it:
     - $admonitions := slice (resources.Get "js/adoc-admonitions.js")
        resources.Concat "assets/js/adoc-admonitions.js"   minify   fingerprint  
    <script defer crossorigin="anonymous" src="  $admonitions.RelPermalink  "
      integrity="  $admonitions.Data.Integrity  "></script>

Remark42 configurationTo integrate Remark42 with the PaperMod theme I ve created the file layouts/partials/comments.html with the following content based on the remark42 documentation, including extra code to sync the dark/light setting with the one set on the site:
comments.html
<div id="remark42"></div>
<script>
  var remark_config =  
    host:   .Site.Params.remark42Url  ,
    site_id:   .Site.Params.remark42SiteID  ,
    url:   .Permalink  ,
    locale:   .Site.Language.Lang  
   ;
  (function(c)  
    /* Adjust the theme using the local-storage pref-theme if set */
    if (localStorage.getItem("pref-theme") === "dark")  
      remark_config.theme = "dark";
      else if (localStorage.getItem("pref-theme") === "light")  
      remark_config.theme = "light";
     
    /* Add remark42 widget */
    for(var i = 0; i < c.length; i++) 
      var d = document, s = d.createElement('script');
      s.src = remark_config.host + '/web/' + c[i] +'.js';
      s.defer = true;
      (d.head   d.body).appendChild(s);
     
   )(remark_config.components   ['embed']);
</script>
In development I use it with anonymous comments enabled, but to avoid SPAM the production site uses social logins (for now I ve only enabled Github & Google, if someone requests additional services I ll check them, but those were the easy ones for me initially). To support theme switching with remark42 I ve also added the following inside the layouts/partials/extend_footer.html file:
 - if (not site.Params.disableThemeToggle)  
<script>
/* Function to change theme when the toggle button is pressed */
document.getElementById("theme-toggle").addEventListener("click", () =>  
  if (typeof window.REMARK42 != "undefined")  
    if (document.body.className.includes('dark'))  
      window.REMARK42.changeTheme('light');
      else  
      window.REMARK42.changeTheme('dark');
     
   
 );
</script>
 - end  
With this code if the theme-toggle button is pressed we change the remark42 theme before the PaperMod one (that s needed here only, on page loads the remark42 theme is synced with the main one using the code from the layouts/partials/comments.html shown earlier).

Development setupTo preview the site on my laptop I m using docker-compose with the following configuration:
docker-compose.yaml
version: "2"
services:
  hugo:
    build:
      context: ./docker/hugo-adoc
      dockerfile: ./Dockerfile
    image: sto/hugo-adoc
    container_name: hugo-adoc-blogops
    restart: always
    volumes:
      - .:/documents
    command: server --bind 0.0.0.0 -D -F
    user: $ APP_UID :$ APP_GID 
  nginx:
    image: nginx:latest
    container_name: nginx-blogops
    restart: always
    volumes:
      - ./nginx/default.conf:/etc/nginx/conf.d/default.conf
    ports:
      -  1313:1313
  remark42:
    build:
      context: ./docker/remark42
      dockerfile: ./Dockerfile
    image: sto/remark42
    container_name: remark42-blogops
    restart: always
    env_file:
      - ./.env
      - ./remark42/env.dev
    volumes:
      - ./remark42/var.dev:/srv/var
To run it properly we have to create the .env file with the current user ID and GID on the variables APP_UID and APP_GID (if we don t do it the files can end up being owned by a user that is not the same as the one running the services):
$ echo "APP_UID=$(id -u)\nAPP_GID=$(id -g)" > .env
The Dockerfile used to generate the sto/hugo-adoc is:
Dockerfile
FROM asciidoctor/docker-asciidoctor:latest
RUN gem install --no-document asciidoctor-html5s &&\
 apk update && apk add --no-cache curl libc6-compat &&\
 repo_path="gohugoio/hugo" &&\
 api_url="https://api.github.com/repos/$repo_path/releases/latest" &&\
 download_url="$(\
  curl -sL "$api_url"  \
  sed -n "s/^.*download_url\": \"\\(.*.extended.*Linux-64bit.tar.gz\)\"/\1/p"\
 )" &&\
 curl -sL "$download_url" -o /tmp/hugo.tgz &&\
 tar xf /tmp/hugo.tgz hugo &&\
 install hugo /usr/bin/ &&\
 rm -f hugo /tmp/hugo.tgz &&\
 /usr/bin/hugo version &&\
 apk del curl && rm -rf /var/cache/apk/*
# Expose port for live server
EXPOSE 1313
ENTRYPOINT ["/usr/bin/hugo"]
CMD [""]
If you review it you will see that I m using the docker-asciidoctor image as the base; the idea is that this image has all I need to work with asciidoctor and to use hugo I only need to download the binary from their latest release at github (as we are using an image based on alpine we also need to install the libc6-compat package, but once that is done things are working fine for me so far). The image does not launch the server by default because I don t want it to; in fact I use the same docker-compose.yml file to publish the site in production simply calling the container without the arguments passed on the docker-compose.yml file (see later). When running the containers with docker-compose up (or docker compose up if you have the docker-compose-plugin package installed) we also launch a nginx container and the remark42 service so we can test everything together. The Dockerfile for the remark42 image is the original one with an updated version of the init.sh script:
Dockerfile
FROM umputun/remark42:latest
COPY init.sh /init.sh
The updated init.sh is similar to the original, but allows us to use an APP_GID variable and updates the /etc/group file of the container so the files get the right user and group (with the original script the group is always 1001):
init.sh
#!/sbin/dinit /bin/sh
uid="$(id -u)"
if [ "$ uid " -eq "0" ]; then
  echo "init container"
  # set container's time zone
  cp "/usr/share/zoneinfo/$ TIME_ZONE " /etc/localtime
  echo "$ TIME_ZONE " >/etc/timezone
  echo "set timezone $ TIME_ZONE  ($(date))"
  # set UID & GID for the app
  if [ "$ APP_UID " ]   [ "$ APP_GID " ]; then
    [ "$ APP_UID " ]   APP_UID="1001"
    [ "$ APP_GID " ]   APP_GID="$ APP_UID "
    echo "set custom APP_UID=$ APP_UID  & APP_GID=$ APP_GID "
    sed -i "s/^app:x:1001:1001:/app:x:$ APP_UID :$ APP_GID :/" /etc/passwd
    sed -i "s/^app:x:1001:/app:x:$ APP_GID :/" /etc/group
  else
    echo "custom APP_UID and/or APP_GID not defined, using 1001:1001"
  fi
  chown -R app:app /srv /home/app
fi
echo "prepare environment"
# replace  % REMARK_URL %  by content of REMARK_URL variable
find /srv -regex '.*\.\(html\ js\ mjs\)$' -print \
  -exec sed -i "s % REMARK_URL % $ REMARK_URL  g"   \;
if [ -n "$ SITE_ID " ]; then
  #replace "site_id: 'remark'" by SITE_ID
  sed -i "s 'remark' '$ SITE_ID ' g" /srv/web/*.html
fi
echo "execute \"$*\""
if [ "$ uid " -eq "0" ]; then
  exec su-exec app "$@"
else
  exec "$@"
fi
The environment file used with remark42 for development is quite minimal:
env.dev
TIME_ZONE=Europe/Madrid
REMARK_URL=http://localhost:1313/remark42
SITE=blogops
SECRET=123456
ADMIN_SHARED_ID=sto
AUTH_ANON=true
EMOJI=true
And the nginx/default.conf file used to publish the service locally is simple too:
default.conf
server   
 listen 1313;
 server_name localhost;
 location /  
    proxy_pass http://hugo:1313;
    proxy_set_header Host $http_host;
    proxy_set_header X-Real-IP $remote_addr;
    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
    proxy_set_header X-Forwarded-Proto $scheme;
    proxy_set_header Upgrade $http_upgrade;
    proxy_set_header Connection "upgrade";
  
 location /remark42/  
    rewrite /remark42/(.*) /$1 break;
    proxy_pass http://remark42:8080/;
    proxy_set_header Host $http_host;
    proxy_set_header X-Real-IP $remote_addr;
    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
    proxy_set_header X-Forwarded-Proto $scheme;
   
 

Production setupThe VM where I m publishing the blog runs Debian GNU/Linux and uses binaries from local packages and applications packaged inside containers. To run the containers I m using docker-ce (I could have used podman instead, but I already had it installed on the machine, so I stayed with it). The binaries used on this project are included on the following packages from the main Debian repository:
  • git to clone & pull the repository,
  • jq to parse json files from shell scripts,
  • json2file-go to save the webhook messages to files,
  • inotify-tools to detect when new files are stored by json2file-go and launch scripts to process them,
  • nginx to publish the site using HTTPS and work as proxy for json2file-go and remark42 (I run it using a container),
  • task-spool to queue the scripts that update the deployment.
And I m using docker and docker compose from the debian packages on the docker repository:
  • docker-ce to run the containers,
  • docker-compose-plugin to run docker compose (it is a plugin, so no - in the name).

Repository checkoutTo manage the git repository I ve created a deploy key, added it to gitea and cloned the project on the /srv/blogops PATH (that route is owned by a regular user that has permissions to run docker, as I said before).

Compiling the site with hugoTo compile the site we are using the docker-compose.yml file seen before, to be able to run it first we build the container images and once we have them we launch hugo using docker compose run:
$ cd /srv/blogops
$ git pull
$ docker compose build
$ if [ -d "./public" ]; then rm -rf ./public; fi
$ docker compose run hugo --
The compilation leaves the static HTML on /srv/blogops/public (we remove the directory first because hugo does not clean the destination folder as jekyll does). The deploy script re-generates the site as described and moves the public directory to its final place for publishing.

Running remark42 with dockerOn the /srv/blogops/remark42 folder I have the following docker-compose.yml:
docker-compose.yml
version: "2"
services:
  remark42:
    build:
      context: ../docker/remark42
      dockerfile: ./Dockerfile
    image: sto/remark42
    env_file:
      - ../.env
      - ./env.prod
    container_name: remark42
    restart: always
    volumes:
      - ./var.prod:/srv/var
    ports:
      - 127.0.0.1:8042:8080
The ../.env file is loaded to get the APP_UID and APP_GID variables that are used by my version of the init.sh script to adjust file permissions and the env.prod file contains the rest of the settings for remark42, including the social network tokens (see the remark42 documentation for the available parameters, I don t include my configuration here because some of them are secrets).

Nginx configurationThe nginx configuration for the blogops.mixinet.net site is as simple as:
server  
  listen 443 ssl http2;
  server_name blogops.mixinet.net;
  ssl_certificate /etc/letsencrypt/live/blogops.mixinet.net/fullchain.pem;
  ssl_certificate_key /etc/letsencrypt/live/blogops.mixinet.net/privkey.pem;
  include /etc/letsencrypt/options-ssl-nginx.conf;
  ssl_dhparam /etc/letsencrypt/ssl-dhparams.pem;
  access_log /var/log/nginx/blogops.mixinet.net-443.access.log;
  error_log  /var/log/nginx/blogops.mixinet.net-443.error.log;
  root /srv/blogops/nginx/public_html;
  location /  
    try_files $uri $uri/ =404;
   
  include /srv/blogops/nginx/remark42.conf;
 
server  
  listen 80 ;
  listen [::]:80 ;
  server_name blogops.mixinet.net;
  access_log /var/log/nginx/blogops.mixinet.net-80.access.log;
  error_log  /var/log/nginx/blogops.mixinet.net-80.error.log;
  if ($host = blogops.mixinet.net)  
    return 301 https://$host$request_uri;
   
  return 404;
 
On this configuration the certificates are managed by certbot and the server root directory is on /srv/blogops/nginx/public_html and not on /srv/blogops/public; the reason for that is that I want to be able to compile without affecting the running site, the deployment script generates the site on /srv/blogops/public and if all works well we rename folders to do the switch, making the change feel almost atomic.

json2file-go configurationAs I have a working WireGuard VPN between the machine running gitea at my home and the VM where the blog is served, I m going to configure the json2file-go to listen for connections on a high port using a self signed certificate and listening on IP addresses only reachable through the VPN. To do it we create a systemd socket to run json2file-go and adjust its configuration to listen on a private IP (we use the FreeBind option on its definition to be able to launch the service even when the IP is not available, that is, when the VPN is down). The following script can be used to set up the json2file-go configuration:
setup-json2file.sh
#!/bin/sh
set -e
# ---------
# VARIABLES
# ---------
BASE_DIR="/srv/blogops/webhook"
J2F_DIR="$BASE_DIR/json2file"
TLS_DIR="$BASE_DIR/tls"
J2F_SERVICE_NAME="json2file-go"
J2F_SERVICE_DIR="/etc/systemd/system/json2file-go.service.d"
J2F_SERVICE_OVERRIDE="$J2F_SERVICE_DIR/override.conf"
J2F_SOCKET_DIR="/etc/systemd/system/json2file-go.socket.d"
J2F_SOCKET_OVERRIDE="$J2F_SOCKET_DIR/override.conf"
J2F_BASEDIR_FILE="/etc/json2file-go/basedir"
J2F_DIRLIST_FILE="/etc/json2file-go/dirlist"
J2F_CRT_FILE="/etc/json2file-go/certfile"
J2F_KEY_FILE="/etc/json2file-go/keyfile"
J2F_CRT_PATH="$TLS_DIR/crt.pem"
J2F_KEY_PATH="$TLS_DIR/key.pem"
# ----
# MAIN
# ----
# Install packages used with json2file for the blogops site
sudo apt update
sudo apt install -y json2file-go uuid
if [ -z "$(type mkcert)" ]; then
  sudo apt install -y mkcert
fi
sudo apt clean
# Configuration file values
J2F_USER="$(id -u)"
J2F_GROUP="$(id -g)"
J2F_DIRLIST="blogops:$(uuid)"
J2F_LISTEN_STREAM="172.31.31.1:4443"
# Configure json2file
[ -d "$J2F_DIR" ]   mkdir "$J2F_DIR"
sudo sh -c "echo '$J2F_DIR' >'$J2F_BASEDIR_FILE'"
[ -d "$TLS_DIR" ]   mkdir "$TLS_DIR"
if [ ! -f "$J2F_CRT_PATH" ]   [ ! -f "$J2F_KEY_PATH" ]; then
  mkcert -cert-file "$J2F_CRT_PATH" -key-file "$J2F_KEY_PATH" "$(hostname -f)"
fi
sudo sh -c "echo '$J2F_CRT_PATH' >'$J2F_CRT_FILE'"
sudo sh -c "echo '$J2F_KEY_PATH' >'$J2F_KEY_FILE'"
sudo sh -c "cat >'$J2F_DIRLIST_FILE'" <<EOF
$(echo "$J2F_DIRLIST"   tr ';' '\n')
EOF
# Service override
[ -d "$J2F_SERVICE_DIR" ]   sudo mkdir "$J2F_SERVICE_DIR"
sudo sh -c "cat >'$J2F_SERVICE_OVERRIDE'" <<EOF
[Service]
User=$J2F_USER
Group=$J2F_GROUP
EOF
# Socket override
[ -d "$J2F_SOCKET_DIR" ]   sudo mkdir "$J2F_SOCKET_DIR"
sudo sh -c "cat >'$J2F_SOCKET_OVERRIDE'" <<EOF
[Socket]
# Set FreeBind to listen on missing addresses (the VPN can be down sometimes)
FreeBind=true
# Set ListenStream to nothing to clear its value and add the new value later
ListenStream=
ListenStream=$J2F_LISTEN_STREAM
EOF
# Restart and enable service
sudo systemctl daemon-reload
sudo systemctl stop "$J2F_SERVICE_NAME"
sudo systemctl start "$J2F_SERVICE_NAME"
sudo systemctl enable "$J2F_SERVICE_NAME"
# ----
# vim: ts=2:sw=2:et:ai:sts=2
Warning: The script uses mkcert to create the temporary certificates, to install the package on bullseye the backports repository must be available.

Gitea configurationTo make gitea use our json2file-go server we go to the project and enter into the hooks/gitea/new page, once there we create a new webhook of type gitea and set the target URL to https://172.31.31.1:4443/blogops and on the secret field we put the token generated with uuid by the setup script:
sed -n -e 's/blogops://p' /etc/json2file-go/dirlist
The rest of the settings can be left as they are:
  • Trigger on: Push events
  • Branch filter: *
Warning: We are using an internal IP and a self signed certificate, that means that we have to review that the webhook section of the app.ini of our gitea server allows us to call the IP and skips the TLS verification (you can see the available options on the gitea documentation). The [webhook] section of my server looks like this:
[webhook]
ALLOWED_HOST_LIST=private
SKIP_TLS_VERIFY=true
Once we have the webhook configured we can try it and if it works our json2file server will store the file on the /srv/blogops/webhook/json2file/blogops/ folder.

The json2file spooler scriptWith the previous configuration our system is ready to receive webhook calls from gitea and store the messages on files, but we have to do something to process those files once they are saved in our machine. An option could be to use a cronjob to look for new files, but we can do better on Linux using inotify we will use the inotifywait command from inotify-tools to watch the json2file output directory and execute a script each time a new file is moved inside it or closed after writing (IN_CLOSE_WRITE and IN_MOVED_TO events). To avoid concurrency problems we are going to use task-spooler to launch the scripts that process the webhooks using a queue of length 1, so they are executed one by one in a FIFO queue. The spooler script is this:
blogops-spooler.sh
#!/bin/sh
set -e
# ---------
# VARIABLES
# ---------
BASE_DIR="/srv/blogops/webhook"
BIN_DIR="$BASE_DIR/bin"
TSP_DIR="$BASE_DIR/tsp"
WEBHOOK_COMMAND="$BIN_DIR/blogops-webhook.sh"
# ---------
# FUNCTIONS
# ---------
queue_job()  
  echo "Queuing job to process file '$1'"
  TMPDIR="$TSP_DIR" TS_SLOTS="1" TS_MAXFINISHED="10" \
    tsp -n "$WEBHOOK_COMMAND" "$1"
 
# ----
# MAIN
# ----
INPUT_DIR="$1"
if [ ! -d "$INPUT_DIR" ]; then
  echo "Input directory '$INPUT_DIR' does not exist, aborting!"
  exit 1
fi
[ -d "$TSP_DIR" ]   mkdir "$TSP_DIR"
echo "Processing existing files under '$INPUT_DIR'"
find "$INPUT_DIR" -type f   sort   while read -r _filename; do
  queue_job "$_filename"
done
# Use inotifywatch to process new files
echo "Watching for new files under '$INPUT_DIR'"
inotifywait -q -m -e close_write,moved_to --format "%w%f" -r "$INPUT_DIR"  
  while read -r _filename; do
    queue_job "$_filename"
  done
# ----
# vim: ts=2:sw=2:et:ai:sts=2
To run it as a daemon we install it as a systemd service using the following script:
setup-spooler.sh
#!/bin/sh
set -e
# ---------
# VARIABLES
# ---------
BASE_DIR="/srv/blogops/webhook"
BIN_DIR="$BASE_DIR/bin"
J2F_DIR="$BASE_DIR/json2file"
SPOOLER_COMMAND="$BIN_DIR/blogops-spooler.sh '$J2F_DIR'"
SPOOLER_SERVICE_NAME="blogops-j2f-spooler"
SPOOLER_SERVICE_FILE="/etc/systemd/system/$SPOOLER_SERVICE_NAME.service"
# Configuration file values
J2F_USER="$(id -u)"
J2F_GROUP="$(id -g)"
# ----
# MAIN
# ----
# Install packages used with the webhook processor
sudo apt update
sudo apt install -y inotify-tools jq task-spooler
sudo apt clean
# Configure process service
sudo sh -c "cat > $SPOOLER_SERVICE_FILE" <<EOF
[Install]
WantedBy=multi-user.target
[Unit]
Description=json2file processor for $J2F_USER
After=docker.service
[Service]
Type=simple
User=$J2F_USER
Group=$J2F_GROUP
ExecStart=$SPOOLER_COMMAND
EOF
# Restart and enable service
sudo systemctl daemon-reload
sudo systemctl stop "$SPOOLER_SERVICE_NAME"   true
sudo systemctl start "$SPOOLER_SERVICE_NAME"
sudo systemctl enable "$SPOOLER_SERVICE_NAME"
# ----
# vim: ts=2:sw=2:et:ai:sts=2

The gitea webhook processorFinally, the script that processes the JSON files does the following:
  1. First, it checks if the repository and branch are right,
  2. Then, it fetches and checks out the commit referenced on the JSON file,
  3. Once the files are updated, compiles the site using hugo with docker compose,
  4. If the compilation succeeds the script renames directories to swap the old version of the site by the new one.
If there is a failure the script aborts but before doing it or if the swap succeeded the system sends an email to the configured address and/or the user that pushed updates to the repository with a log of what happened. The current script is this one:
blogops-webhook.sh
#!/bin/sh
set -e
# ---------
# VARIABLES
# ---------
# Values
REPO_REF="refs/heads/main"
REPO_CLONE_URL="https://gitea.mixinet.net/mixinet/blogops.git"
MAIL_PREFIX="[BLOGOPS-WEBHOOK] "
# Address that gets all messages, leave it empty if not wanted
MAIL_TO_ADDR="blogops@mixinet.net"
# If the following variable is set to 'true' the pusher gets mail on failures
MAIL_ERRFILE="false"
# If the following variable is set to 'true' the pusher gets mail on success
MAIL_LOGFILE="false"
# gitea's conf/app.ini value of NO_REPLY_ADDRESS, it is used for email domains
# when the KeepEmailPrivate option is enabled for a user
NO_REPLY_ADDRESS="noreply.example.org"
# Directories
BASE_DIR="/srv/blogops"
PUBLIC_DIR="$BASE_DIR/public"
NGINX_BASE_DIR="$BASE_DIR/nginx"
PUBLIC_HTML_DIR="$NGINX_BASE_DIR/public_html"
WEBHOOK_BASE_DIR="$BASE_DIR/webhook"
WEBHOOK_SPOOL_DIR="$WEBHOOK_BASE_DIR/spool"
WEBHOOK_ACCEPTED="$WEBHOOK_SPOOL_DIR/accepted"
WEBHOOK_DEPLOYED="$WEBHOOK_SPOOL_DIR/deployed"
WEBHOOK_REJECTED="$WEBHOOK_SPOOL_DIR/rejected"
WEBHOOK_TROUBLED="$WEBHOOK_SPOOL_DIR/troubled"
WEBHOOK_LOG_DIR="$WEBHOOK_SPOOL_DIR/log"
# Files
TODAY="$(date +%Y%m%d)"
OUTPUT_BASENAME="$(date +%Y%m%d-%H%M%S.%N)"
WEBHOOK_LOGFILE_PATH="$WEBHOOK_LOG_DIR/$OUTPUT_BASENAME.log"
WEBHOOK_ACCEPTED_JSON="$WEBHOOK_ACCEPTED/$OUTPUT_BASENAME.json"
WEBHOOK_ACCEPTED_LOGF="$WEBHOOK_ACCEPTED/$OUTPUT_BASENAME.log"
WEBHOOK_REJECTED_TODAY="$WEBHOOK_REJECTED/$TODAY"
WEBHOOK_REJECTED_JSON="$WEBHOOK_REJECTED_TODAY/$OUTPUT_BASENAME.json"
WEBHOOK_REJECTED_LOGF="$WEBHOOK_REJECTED_TODAY/$OUTPUT_BASENAME.log"
WEBHOOK_DEPLOYED_TODAY="$WEBHOOK_DEPLOYED/$TODAY"
WEBHOOK_DEPLOYED_JSON="$WEBHOOK_DEPLOYED_TODAY/$OUTPUT_BASENAME.json"
WEBHOOK_DEPLOYED_LOGF="$WEBHOOK_DEPLOYED_TODAY/$OUTPUT_BASENAME.log"
WEBHOOK_TROUBLED_TODAY="$WEBHOOK_TROUBLED/$TODAY"
WEBHOOK_TROUBLED_JSON="$WEBHOOK_TROUBLED_TODAY/$OUTPUT_BASENAME.json"
WEBHOOK_TROUBLED_LOGF="$WEBHOOK_TROUBLED_TODAY/$OUTPUT_BASENAME.log"
# Query to get variables from a gitea webhook json
ENV_VARS_QUERY="$(
  printf "%s" \
    '(.             @sh "gt_ref=\(.ref);"),' \
    '(.             @sh "gt_after=\(.after);"),' \
    '(.repository   @sh "gt_repo_clone_url=\(.clone_url);"),' \
    '(.repository   @sh "gt_repo_name=\(.name);"),' \
    '(.pusher       @sh "gt_pusher_full_name=\(.full_name);"),' \
    '(.pusher       @sh "gt_pusher_email=\(.email);")'
)"
# ---------
# Functions
# ---------
webhook_log()  
  echo "$(date -R) $*" >>"$WEBHOOK_LOGFILE_PATH"
 
webhook_check_directories()  
  for _d in "$WEBHOOK_SPOOL_DIR" "$WEBHOOK_ACCEPTED" "$WEBHOOK_DEPLOYED" \
    "$WEBHOOK_REJECTED" "$WEBHOOK_TROUBLED" "$WEBHOOK_LOG_DIR"; do
    [ -d "$_d" ]   mkdir "$_d"
  done
 
webhook_clean_directories()  
  # Try to remove empty dirs
  for _d in "$WEBHOOK_ACCEPTED" "$WEBHOOK_DEPLOYED" "$WEBHOOK_REJECTED" \
    "$WEBHOOK_TROUBLED" "$WEBHOOK_LOG_DIR" "$WEBHOOK_SPOOL_DIR"; do
    if [ -d "$_d" ]; then
      rmdir "$_d" 2>/dev/null   true
    fi
  done
 
webhook_accept()  
  webhook_log "Accepted: $*"
  mv "$WEBHOOK_JSON_INPUT_FILE" "$WEBHOOK_ACCEPTED_JSON"
  mv "$WEBHOOK_LOGFILE_PATH" "$WEBHOOK_ACCEPTED_LOGF"
  WEBHOOK_LOGFILE_PATH="$WEBHOOK_ACCEPTED_LOGF"
 
webhook_reject()  
  [ -d "$WEBHOOK_REJECTED_TODAY" ]   mkdir "$WEBHOOK_REJECTED_TODAY"
  webhook_log "Rejected: $*"
  if [ -f "$WEBHOOK_JSON_INPUT_FILE" ]; then
    mv "$WEBHOOK_JSON_INPUT_FILE" "$WEBHOOK_REJECTED_JSON"
  fi
  mv "$WEBHOOK_LOGFILE_PATH" "$WEBHOOK_REJECTED_LOGF"
  exit 0
 
webhook_deployed()  
  [ -d "$WEBHOOK_DEPLOYED_TODAY" ]   mkdir "$WEBHOOK_DEPLOYED_TODAY"
  webhook_log "Deployed: $*"
  mv "$WEBHOOK_ACCEPTED_JSON" "$WEBHOOK_DEPLOYED_JSON"
  mv "$WEBHOOK_ACCEPTED_LOGF" "$WEBHOOK_DEPLOYED_LOGF"
  WEBHOOK_LOGFILE_PATH="$WEBHOOK_DEPLOYED_LOGF"
 
webhook_troubled()  
  [ -d "$WEBHOOK_TROUBLED_TODAY" ]   mkdir "$WEBHOOK_TROUBLED_TODAY"
  webhook_log "Troubled: $*"
  mv "$WEBHOOK_ACCEPTED_JSON" "$WEBHOOK_TROUBLED_JSON"
  mv "$WEBHOOK_ACCEPTED_LOGF" "$WEBHOOK_TROUBLED_LOGF"
  WEBHOOK_LOGFILE_PATH="$WEBHOOK_TROUBLED_LOGF"
 
print_mailto()  
  _addr="$1"
  _user_email=""
  # Add the pusher email address unless it is from the domain NO_REPLY_ADDRESS,
  # which should match the value of that variable on the gitea 'app.ini' (it
  # is the domain used for emails when the user hides it).
  # shellcheck disable=SC2154
  if [ -n "$ gt_pusher_email##*@"$ NO_REPLY_ADDRESS " " ] &&
    [ -z "$ gt_pusher_email##*@* " ]; then
    _user_email="\"$gt_pusher_full_name <$gt_pusher_email>\""
  fi
  if [ "$_addr" ] && [ "$_user_email" ]; then
    echo "$_addr,$_user_email"
  elif [ "$_user_email" ]; then
    echo "$_user_email"
  elif [ "$_addr" ]; then
    echo "$_addr"
  fi
 
mail_success()  
  to_addr="$MAIL_TO_ADDR"
  if [ "$MAIL_LOGFILE" = "true" ]; then
    to_addr="$(print_mailto "$to_addr")"
  fi
  if [ "$to_addr" ]; then
    # shellcheck disable=SC2154
    subject="OK - $gt_repo_name updated to commit '$gt_after'"
    mail -s "$ MAIL_PREFIX $ subject " "$to_addr" \
      <"$WEBHOOK_LOGFILE_PATH"
  fi
 
mail_failure()  
  to_addr="$MAIL_TO_ADDR"
  if [ "$MAIL_ERRFILE" = true ]; then
    to_addr="$(print_mailto "$to_addr")"
  fi
  if [ "$to_addr" ]; then
    # shellcheck disable=SC2154
    subject="KO - $gt_repo_name update FAILED for commit '$gt_after'"
    mail -s "$ MAIL_PREFIX $ subject " "$to_addr" \
      <"$WEBHOOK_LOGFILE_PATH"
  fi
 
# ----
# MAIN
# ----
# Check directories
webhook_check_directories
# Go to the base directory
cd "$BASE_DIR"
# Check if the file exists
WEBHOOK_JSON_INPUT_FILE="$1"
if [ ! -f "$WEBHOOK_JSON_INPUT_FILE" ]; then
  webhook_reject "Input arg '$1' is not a file, aborting"
fi
# Parse the file
webhook_log "Processing file '$WEBHOOK_JSON_INPUT_FILE'"
eval "$(jq -r "$ENV_VARS_QUERY" "$WEBHOOK_JSON_INPUT_FILE")"
# Check that the repository clone url is right
# shellcheck disable=SC2154
if [ "$gt_repo_clone_url" != "$REPO_CLONE_URL" ]; then
  webhook_reject "Wrong repository: '$gt_clone_url'"
fi
# Check that the branch is the right one
# shellcheck disable=SC2154
if [ "$gt_ref" != "$REPO_REF" ]; then
  webhook_reject "Wrong repository ref: '$gt_ref'"
fi
# Accept the file
# shellcheck disable=SC2154
webhook_accept "Processing '$gt_repo_name'"
# Update the checkout
ret="0"
git fetch >>"$WEBHOOK_LOGFILE_PATH" 2>&1   ret="$?"
if [ "$ret" -ne "0" ]; then
  webhook_troubled "Repository fetch failed"
  mail_failure
fi
# shellcheck disable=SC2154
git checkout "$gt_after" >>"$WEBHOOK_LOGFILE_PATH" 2>&1   ret="$?"
if [ "$ret" -ne "0" ]; then
  webhook_troubled "Repository checkout failed"
  mail_failure
fi
# Remove the build dir if present
if [ -d "$PUBLIC_DIR" ]; then
  rm -rf "$PUBLIC_DIR"
fi
# Build site
docker compose run hugo -- >>"$WEBHOOK_LOGFILE_PATH" 2>&1   ret="$?"
# go back to the main branch
git switch main && git pull
# Fail if public dir was missing
if [ "$ret" -ne "0" ]   [ ! -d "$PUBLIC_DIR" ]; then
  webhook_troubled "Site build failed"
  mail_failure
fi
# Remove old public_html copies
webhook_log 'Removing old site versions, if present'
find $NGINX_BASE_DIR -mindepth 1 -maxdepth 1 -name 'public_html-*' -type d \
  -exec rm -rf   \; >>"$WEBHOOK_LOGFILE_PATH" 2>&1   ret="$?"
if [ "$ret" -ne "0" ]; then
  webhook_troubled "Removal of old site versions failed"
  mail_failure
fi
# Switch site directory
TS="$(date +%Y%m%d-%H%M%S)"
if [ -d "$PUBLIC_HTML_DIR" ]; then
  webhook_log "Moving '$PUBLIC_HTML_DIR' to '$PUBLIC_HTML_DIR-$TS'"
  mv "$PUBLIC_HTML_DIR" "$PUBLIC_HTML_DIR-$TS" >>"$WEBHOOK_LOGFILE_PATH" 2>&1  
    ret="$?"
fi
if [ "$ret" -eq "0" ]; then
  webhook_log "Moving '$PUBLIC_DIR' to '$PUBLIC_HTML_DIR'"
  mv "$PUBLIC_DIR" "$PUBLIC_HTML_DIR" >>"$WEBHOOK_LOGFILE_PATH" 2>&1  
    ret="$?"
fi
if [ "$ret" -ne "0" ]; then
  webhook_troubled "Site switch failed"
  mail_failure
else
  webhook_deployed "Site deployed successfully"
  mail_success
fi
# ----
# vim: ts=2:sw=2:et:ai:sts=2

19 May 2022

Agathe Porte: Status update, May 2022

Boing, time for another status update.
Debian work I have finally found how to make my fonts-creep2 package work on my Debian machines. The solution was to not use the TTF file that contains the Bitmap glyphs, but instead generate an OTB file, which is an OpenType format for Bitmap fonts. Creep2 font used in htop command This means that I can close the fonts-creep ITP bug altogether and rely on this fonts-creep2 package instead. Hopefully it will be reviewed and uploaded soon by a certified Debian Developer. This font is too small for daily usage, but imagine the quantity of data you could display on an auxiliary screen with poor resolution (and poor pixel density eventually). Here is a meme I created for the occasion: Hide the pain Harold meme. First: Package software and its gazillion dependencies. Second: Popcon says I'm the only user. Checks out.
Rust work I have obsoleted my most popular Rust crate, gladis. Screenshot of the Gladis Github README Indeed, the GTK folks have managed to develop a similar solution named CompositeTemplate, that is available in both gtk3-macros and gtk4-macros crates. I did not investigate from how long this has been available before I created this crate. Hopefully it did not exist before I developed it. I have learnt a lot about Rust crates development with this crate, and managed to put in place a semi-automated release flow that I will surely use in other future crates. See ya.

13 May 2022

Antoine Beaupr : BTRFS notes

I'm not a fan of BTRFS. This page serves as a reminder of why, but also a cheat sheet to figure out basic tasks in a BTRFS environment because those are not obvious to me, even after repeatedly having to deal with them. Content warning: there might be mentions of ZFS.

Stability concerns I'm worried about BTRFS stability, which has been historically ... changing. RAID-5 and RAID-6 are still marked unstable, for example. It's kind of a lucky guess whether your current kernel will behave properly with your planned workload. For example, in Linux 4.9, RAID-1 and RAID-10 were marked as "mostly OK" with a note that says:
Needs to be able to create two copies always. Can get stuck in irreversible read-only mode if only one copy can be made.
Even as of now, RAID-1 and RAID-10 has this note:
The simple redundancy RAID levels utilize different mirrors in a way that does not achieve the maximum performance. The logic can be improved so the reads will spread over the mirrors evenly or based on device congestion.
Granted, that's not a stability concern anymore, just performance. A reviewer of a draft of this article actually claimed that BTRFS only reads from one of the drives, which hopefully is inaccurate, but goes to show how confusing all this is. There are other warnings in the Debian wiki that are quite scary. Even the legendary Arch wiki has a warning on top of their BTRFS page, still. Even if those issues are now fixed, it can be hard to tell when they were fixed. There is a changelog by feature but it explicitly warns that it doesn't know "which kernel version it is considered mature enough for production use", so it's also useless for this. It would have been much better if BTRFS was released into the world only when those bugs were being completely fixed. Or that, at least, features were announced when they were stable, not just "we merged to mainline, good luck". Even now, we get mixed messages even in the official BTRFS documentation which says "The Btrfs code base is stable" (main page) while at the same time clearly stating unstable parts in the status page (currently RAID56). There are much harsher BTRFS critics than me out there so I will stop here, but let's just say that I feel a little uncomfortable trusting server data with full RAID arrays to BTRFS. But surely, for a workstation, things should just work smoothly... Right? Well, let's see the snags I hit.

My BTRFS test setup Before I go any further, I should probably clarify how I am testing BTRFS in the first place. The reason I tried BTRFS is that I was ... let's just say "strongly encouraged" by the LWN editors to install Fedora for the terminal emulators series. That, in turn, meant the setup was done with BTRFS, because that was somewhat the default in Fedora 27 (or did I want to experiment? I don't remember, it's been too long already). So Fedora was setup on my 1TB HDD and, with encryption, the partition table looks like this:
NAME                   MAJ:MIN RM   SIZE RO TYPE  MOUNTPOINT
sda                      8:0    0 931,5G  0 disk  
 sda1                   8:1    0   200M  0 part  /boot/efi
 sda2                   8:2    0     1G  0 part  /boot
 sda3                   8:3    0   7,8G  0 part  
   fedora_swap        253:5    0   7.8G  0 crypt [SWAP]
 sda4                   8:4    0 922,5G  0 part  
   fedora_crypt       253:4    0 922,5G  0 crypt /
(This might not entirely be accurate: I rebuilt this from the Debian side of things.) This is pretty straightforward, except for the swap partition: normally, I just treat swap like any other logical volume and create it in a logical volume. This is now just speculation, but I bet it was setup this way because "swap" support was only added in BTRFS 5.0. I fully expect BTRFS experts to yell at me now because this is an old setup and BTRFS is so much better now, but that's exactly the point here. That setup is not that old (2018? old? really?), and migrating to a new partition scheme isn't exactly practical right now. But let's move on to more practical considerations.

No builtin encryption BTRFS aims at replacing the entire mdadm, LVM, and ext4 stack with a single entity, and adding new features like deduplication, checksums and so on. Yet there is one feature it is critically missing: encryption. See, my typical stack is actually mdadm, LUKS, and then LVM and ext4. This is convenient because I have only a single volume to decrypt. If I were to use BTRFS on servers, I'd need to have one LUKS volume per-disk. For a simple RAID-1 array, that's not too bad: one extra key. But for large RAID-10 arrays, this gets really unwieldy. The obvious BTRFS alternative, ZFS, supports encryption out of the box and mixes it above the disks so you only have one passphrase to enter. The main downside of ZFS encryption is that it happens above the "pool" level so you can typically see filesystem names (and possibly snapshots, depending on how it is built), which is not the case with a more traditional stack.

Subvolumes, filesystems, and devices I find BTRFS's architecture to be utterly confusing. In the traditional LVM stack (which is itself kind of confusing if you're new to that stuff), you have those layers:
  • disks: let's say /dev/nvme0n1 and nvme1n1
  • RAID arrays with mdadm: let's say the above disks are joined in a RAID-1 array in /dev/md1
  • volume groups or VG with LVM: the above RAID device (technically a "physical volume" or PV) is assigned into a VG, let's call it vg_tbbuild05 (multiple PVs can be added to a single VG which is why there is that abstraction)
  • LVM logical volumes: out of that volume group actually "virtual partitions" or "logical volumes" are created, that is where your filesystem lives
  • filesystem, typically with ext4: that's your normal filesystem, which treats the logical volume as just another block device
A typical server setup would look like this:
NAME                      MAJ:MIN RM   SIZE RO TYPE  MOUNTPOINT
nvme0n1                   259:0    0   1.7T  0 disk  
 nvme0n1p1               259:1    0     8M  0 part  
 nvme0n1p2               259:2    0   512M  0 part  
   md0                     9:0    0   511M  0 raid1 /boot
 nvme0n1p3               259:3    0   1.7T  0 part  
   md1                     9:1    0   1.7T  0 raid1 
     crypt_dev_md1       253:0    0   1.7T  0 crypt 
       vg_tbbuild05-root 253:1    0    30G  0 lvm   /
       vg_tbbuild05-swap 253:2    0 125.7G  0 lvm   [SWAP]
       vg_tbbuild05-srv  253:3    0   1.5T  0 lvm   /srv
 nvme0n1p4               259:4    0     1M  0 part
I stripped the other nvme1n1 disk because it's basically the same. Now, if we look at my BTRFS-enabled workstation, which doesn't even have RAID, we have the following:
  • disk: /dev/sda with, again, /dev/sda4 being where BTRFS lives
  • filesystem: fedora_crypt, which is, confusingly, kind of like a volume group. it's where everything lives. i think.
  • subvolumes: home, root, /, etc. those are actually the things that get mounted. you'd think you'd mount a filesystem, but no, you mount a subvolume. that is backwards.
It looks something like this to lsblk:
NAME                   MAJ:MIN RM   SIZE RO TYPE  MOUNTPOINT
sda                      8:0    0 931,5G  0 disk  
 sda1                   8:1    0   200M  0 part  /boot/efi
 sda2                   8:2    0     1G  0 part  /boot
 sda3                   8:3    0   7,8G  0 part  [SWAP]
 sda4                   8:4    0 922,5G  0 part  
   fedora_crypt       253:4    0 922,5G  0 crypt /srv
Notice how we don't see all the BTRFS volumes here? Maybe it's because I'm mounting this from the Debian side, but lsblk definitely gets confused here. I frankly don't quite understand what's going on, even after repeatedly looking around the rather dismal documentation. But that's what I gather from the following commands:
root@curie:/home/anarcat# btrfs filesystem show
Label: 'fedora'  uuid: 5abb9def-c725-44ef-a45e-d72657803f37
    Total devices 1 FS bytes used 883.29GiB
    devid    1 size 922.47GiB used 916.47GiB path /dev/mapper/fedora_crypt
root@curie:/home/anarcat# btrfs subvolume list /srv
ID 257 gen 108092 top level 5 path home
ID 258 gen 108094 top level 5 path root
ID 263 gen 108020 top level 258 path root/var/lib/machines
I only got to that point through trial and error. Notice how I use an existing mountpoint to list the related subvolumes. If I try to use the filesystem path, the one that's listed in filesystem show, I fail:
root@curie:/home/anarcat# btrfs subvolume list /dev/mapper/fedora_crypt 
ERROR: not a btrfs filesystem: /dev/mapper/fedora_crypt
ERROR: can't access '/dev/mapper/fedora_crypt'
Maybe I just need to use the label? Nope:
root@curie:/home/anarcat# btrfs subvolume list fedora
ERROR: cannot access 'fedora': No such file or directory
ERROR: can't access 'fedora'
This is really confusing. I don't even know if I understand this right, and I've been staring at this all afternoon. Hopefully, the lazyweb will correct me eventually. (As an aside, why are they called "subvolumes"? If something is a "sub" of "something else", that "something else" must exist right? But no, BTRFS doesn't have "volumes", it only has "subvolumes". Go figure. Presumably the filesystem still holds "files" though, at least empirically it doesn't seem like it lost anything so far. In any case, at least I can refer to this section in the future, the next time I fumble around the btrfs commandline, as I surely will. I will possibly even update this section as I get better at it, or based on my reader's judicious feedback.

Mounting BTRFS subvolumes So how did I even get to that point? I have this in my /etc/fstab, on the Debian side of things:
UUID=5abb9def-c725-44ef-a45e-d72657803f37   /srv    btrfs  defaults 0   2
This thankfully ignores all the subvolume nonsense because it relies on the UUID. mount tells me that's actually the "root" (? /?) subvolume:
root@curie:/home/anarcat# mount   grep /srv
/dev/mapper/fedora_crypt on /srv type btrfs (rw,relatime,space_cache,subvolid=5,subvol=/)
Let's see if I can mount the other volumes I have on there. Remember that subvolume list showed I had home, root, and var/lib/machines. Let's try root:
mount -o subvol=root /dev/mapper/fedora_crypt /mnt
Interestingly, root is not the same as /, it's a different subvolume! It seems to be the Fedora root (/, really) filesystem. No idea what is happening here. I also have a home subvolume, let's mount it too, for good measure:
mount -o subvol=home /dev/mapper/fedora_crypt /mnt/home
Note that lsblk doesn't notice those two new mountpoints, and that's normal: it only lists block devices and subvolumes (rather inconveniently, I'd say) do not show up as devices:
root@curie:/home/anarcat# lsblk 
NAME                   MAJ:MIN RM   SIZE RO TYPE  MOUNTPOINT
sda                      8:0    0 931,5G  0 disk  
 sda1                   8:1    0   200M  0 part  
 sda2                   8:2    0     1G  0 part  
 sda3                   8:3    0   7,8G  0 part  
 sda4                   8:4    0 922,5G  0 part  
   fedora_crypt       253:4    0 922,5G  0 crypt /srv
This is really, really confusing. Maybe I did something wrong in the setup. Maybe it's because I'm mounting it from outside Fedora. Either way, it just doesn't feel right.

No disk usage per volume If you want to see what's taking up space in one of those subvolumes, tough luck:
root@curie:/home/anarcat# df -h  /srv /mnt /mnt/home
Filesystem                Size  Used Avail Use% Mounted on
/dev/mapper/fedora_crypt  923G  886G   31G  97% /srv
/dev/mapper/fedora_crypt  923G  886G   31G  97% /mnt
/dev/mapper/fedora_crypt  923G  886G   31G  97% /mnt/home
(Notice, in passing, that it looks like the same filesystem is mounted in different places. In that sense, you'd expect /srv and /mnt (and /mnt/home?!) to be exactly the same, but no: they are entirely different directory structures, which I will not call "filesystems" here because everyone's head will explode in sparks of confusion.) Yes, disk space is shared (that's the Size and Avail columns, makes sense). But nope, no cookie for you: they all have the same Used columns, so you need to actually walk the entire filesystem to figure out what each disk takes. (For future reference, that's basically:
root@curie:/home/anarcat# time du -schx /mnt/home /mnt /srv
124M    /mnt/home
7.5G    /mnt
875G    /srv
883G    total
real    2m49.080s
user    0m3.664s
sys 0m19.013s
And yes, that was painfully slow.) ZFS actually has some oddities in that regard, but at least it tells me how much disk each volume (and snapshot) takes:
root@tubman:~# time df -t zfs -h
Filesystem         Size  Used Avail Use% Mounted on
rpool/ROOT/debian  3.5T  1.4G  3.5T   1% /
rpool/var/tmp      3.5T  384K  3.5T   1% /var/tmp
rpool/var/spool    3.5T  256K  3.5T   1% /var/spool
rpool/var/log      3.5T  2.0G  3.5T   1% /var/log
rpool/home/root    3.5T  2.2G  3.5T   1% /root
rpool/home         3.5T  256K  3.5T   1% /home
rpool/srv          3.5T   80G  3.5T   3% /srv
rpool/var/cache    3.5T  114M  3.5T   1% /var/cache
bpool/BOOT/debian  571M   90M  481M  16% /boot
real    0m0.003s
user    0m0.002s
sys 0m0.000s
That's 56360 times faster, by the way. But yes, that's not fair: those in the know will know there's a different command to do what df does with BTRFS filesystems, the btrfs filesystem usage command:
root@curie:/home/anarcat# time btrfs filesystem usage /srv
Overall:
    Device size:         922.47GiB
    Device allocated:        916.47GiB
    Device unallocated:        6.00GiB
    Device missing:          0.00B
    Used:            884.97GiB
    Free (estimated):         30.84GiB  (min: 27.84GiB)
    Free (statfs, df):        30.84GiB
    Data ratio:               1.00
    Metadata ratio:           2.00
    Global reserve:      512.00MiB  (used: 0.00B)
    Multiple profiles:              no
Data,single: Size:906.45GiB, Used:881.61GiB (97.26%)
   /dev/mapper/fedora_crypt  906.45GiB
Metadata,DUP: Size:5.00GiB, Used:1.68GiB (33.58%)
   /dev/mapper/fedora_crypt   10.00GiB
System,DUP: Size:8.00MiB, Used:128.00KiB (1.56%)
   /dev/mapper/fedora_crypt   16.00MiB
Unallocated:
   /dev/mapper/fedora_crypt    6.00GiB
real    0m0,004s
user    0m0,000s
sys 0m0,004s
Almost as fast as ZFS's df! Good job. But wait. That doesn't actually tell me usage per subvolume. Notice it's filesystem usage, not subvolume usage, which unhelpfully refuses to exist. That command only shows that one "filesystem" internal statistics that are pretty opaque.. You can also appreciate that it's wasting 6GB of "unallocated" disk space there: I probably did something Very Wrong and should be punished by Hacker News. I also wonder why it has 1.68GB of "metadata" used... At this point, I just really want to throw that thing out of the window and restart from scratch. I don't really feel like learning the BTRFS internals, as they seem oblique and completely bizarre to me. It feels a little like the state of PHP now: it's actually pretty solid, but built upon so many layers of cruft that I still feel it corrupts my brain every time I have to deal with it (needle or haystack first? anyone?)...

Conclusion I find BTRFS utterly confusing and I'm worried about its reliability. I think a lot of work is needed on usability and coherence before I even consider running this anywhere else than a lab, and that's really too bad, because there are really nice features in BTRFS that would greatly help my workflow. (I want to use filesystem snapshots as high-performance, high frequency backups.) So now I'm experimenting with OpenZFS. It's so much simpler, just works, and it's rock solid. After this 8 minute read, I had a good understanding of how ZFS worked. Here's the 30 seconds overview:
  • vdev: a RAID array
  • vpool: a volume group of vdevs
  • datasets: normal filesystems (or block device, if you want to use another filesystem on top of ZFS)
There's also other special volumes like caches and logs that you can (really easily, compared to LVM caching) use to tweak your setup. You might also want to look at recordsize or ashift to tweak the filesystem to fit better your workload (or deal with drives lying about their sector size, I'm looking at you Samsung), but that's it. Running ZFS on Linux currently involves building kernel modules from scratch on every host, which I think is pretty bad. But I was able to setup a ZFS-only server using this excellent documentation without too much problem. I'm hoping some day the copyright issues are resolved and we can at least ship binary packages, but the politics (e.g. convincing Debian that is the right thing to do) and the logistics (e.g. DKMS auto-builders? is that even a thing? how about signed DKMS packages? fun-fun-fun!) seem really impractical. Who knows, maybe hell will freeze over (again) and Oracle will fix the CDDL. I personally think that we should just completely ignore this problem (which wasn't even supposed to be a problem) and ship binary packages directly, but I'm a pragmatic and do not always fit well with the free software fundamentalists. All of this to say that, short term, we don't have a reliable, advanced filesystem/logical disk manager in Linux. And that's really too bad.

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