Search Results: "cas"

12 October 2010

MJ Ray: Blog Action and Blog Action Day

Blog Action Day approaches on Friday. The call this year is for clean water and some high profile blogs including the UKFCO and the White House will be joining in. But until then, you can look at the wonderful direct blog action by Lars Wirzenius In defense of Nicole and others after this shocking episode. I hope Lars is wrong in this case and the Davids will join together in their common interest to overthrow the Goliath. There is a far longer prelude than Lars describes, going back to the April 2005 launch of Liblime (announcement here). An independently-authored history of Koha and LibLime and the recent problems can be found at LWN.net (US$7/month if you woud like to subscribe and support LWN). Actually, I m not sure if PTFS is even a Goliath. They seem to stomp around a lot, but how big are they? Biggest credible guess I ve seen is 125 people across all products (not only Koha), which is fewer than the 150ish Koha-Community developers (not all supporters). So there you have it: Koha is bigger than PTFS. Literally.

11 October 2010

Lars Wirzenius: In defense of Nicole

In the real world, David does not always win over Goliath. That's sad, but it's true. Particularly in the case of a big corporation using its wealth, influence, and minions to stomp down invividuals, to prevent them from reducing those all-important profits. A corporation must profit, by any means necessary. Profit is more important than people. A corporation has exactly as little ethics, morals, conscience, and good behavior as it can get away with. It all pretty much rests the officers, and their personal balance between greed and being good people. While most CEOs and managers and other decision makers in a corporation aren't going to do big evil, say, have people killed, they might not mind being a little bit nasty occasionally. If you have a large corporation, with a culture of profit-worshipping, you'll have a large number of people willing to be a little bit nasty, and that amounts to a lot of nastiness. That's all a long prelude to this: earlier this year, the PTFS corporation bought Liblime, a competitor. They did this to get a controlling interest on Koha, the free software librarary mangament system. Much to their surprise, you can't buy a healthy free software project like that. The community of users and developers of Koha has resisted PTFS's strongarm tactics. PTFS wants control of the code base, version control systems, mailing lists, domains, web pages, wikis, and decision making, but the community doesn't let them. Right now they are attacking Nicole Engard, the documentation manager for the Koha community, spreading lies about her. Nicole is one of the Koha community members who has spoken against PTFS's actions. She also works for a PTFS competitor, another sin against PTFS. This is an unfortunate situation for Nicole, for Koha, and for free software in general. If corporations like PTFS manage to silence their critics by nastiness, then nastiness is a working strategy and will be used more in the future. We need to squash this every time it happens, so it does not spread. However, for PTFS to lose, Nicole will have to have the courage to stand up against even more aggression. In the old world, before the Internet, this would have been quite hard. She would have had to get newspapers interested in her case. PTFS would almost certainly have been able to prevent that, by using their PR muscle to conduct a smear campaign against her. However, with the Internet, it's easier. Anyone can step up and help defend Nicole. That's what this is. I've never actually met Nicole, but in my brief involvement with the Koha community, she was always helpful and professional. She has, personally, helped Koha and free software spread farther than it would otherwise have. She does good. Like pretty much everyone in the Koha community, she is considerate, polite, and just to a fault, even when dealing with those attacking her. PTFS, on the other hand, has done only one honorable thing that I am aware of: they finally released their version of Koha. Every other action from PTFS seems to be an attempt to gain an upper hand by underhanded stratagems. Luckily, they seem to be failing. Let's see if giving more publicity to the attack on Nicole will make it, too, fail. See Nicole's post about this for more information.

Raphaël Hertzog: 5 reasons why I still contribute to Debian after 12 years

Debian is packaging the free sofware world.If you re using Debian, you know that this distribution is built entirely by volunteers that form a very diverse community. And you could be part of it. But why should you do that? I can t tell for you but I can share my own experience. It s been 12 years since I joined Debian and I m going to tell you what keeps me on board. 1. Technical excellence When facing a new challenge, Debian will strive to do the right thing. This pays off in the long term. In many cases, it means that we will take more time to implement our solution compared to other distributions out there, but this is also the reason why our packaging infrastructure allows us to offer painless upgrades and consistency across all packages. Debian is committed to quality and builds up on his experience thanks to the Debian Policy. My time is precious, I like to spend it on something useful in the long term. 2. Inspiring goals In its social contract, Debian has set out to create a 100% free as in freedom operating system. The criteria defining what constitutes a free work are listed in the Debian Free Software Guidelines (DFSG). While the above is relatively ambitious in itself, it doesn t inspire me much. What makes the difference to me is the emphasis given by the social contract on our users and free software. We don t build a free operating system in the void, we build it for people. Debian s motto the universal operating system can also be interpreted in multiple ways: universal as in for everybody on the world , on all kinds of computers , or for every possible usage . 3. High impact work Knowing that my work is useful to people is important, but it s even better when I know that it will benefit to lots of people. With Ubuntu and the hundreds of other derivatives, there are nowadays literally millions of users impacted by my work. Even an insignificant one second improvement experienced by 10 millions of people represent 115 days of time saved for something else, you get the idea 4. Working with great people Debian has the chance to have lots of smart people on board. There s always someone sharing valuable advice when you read Debian s mailing lists. When I joined in 1998, I was a real newbie and I learned a lot of things by reading and interacting with people more knowledgeable than me. You can still experience the same thing nowadays but there s one caveat: you must cope with various kinds of mailing list contributors including the smart but uncivilized (don t be offended too quickly!) and the occasional troll (best ignore it, don t feed it!). 5. Recognition of work When you contribute to Debian, people get to know you through your contributions. It s very rewarding to be thanked by your peers and by Debian s users. Check out thanks.debian.net to convince you that many people are grateful for the work we put into Debian. So that s it for me. But what about you? What motivates you to contribute year after year, or to start contributing if you re a prospective contributor?
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Evgeni Golov: RC bugs 2010/40

Let s join gregora and zack (and others, too lazy to search for links/names) and fix some RC bugs in Debian!So what happened last week?What does that mean? Two bugs are (almost) closed, two need more work. And this leads me to a feature I miss from http://udd.debian.org/bugs.cgi: a comment field as http://bts.turmzimmer.net/ has it. Will ping lucas about this later today.Oh, and on a side-note, I joined http://ask.debian.net let s help our users :)

John Goerzen: Pump Organs and Music

Two years ago, I wrote about Elvera Voth and the power of love. Back then I wrote about her memories of seeing of service workers, who would be away from their home for 7 years at a time. Elvera remembered a gathering of people at the train station to see them off, and how they sang some German hymns at the occasion. Elvera s done a lot since, including starting an arts in prison program. And today, she hosted a hymn sing at the pump organ in the Friesen House parlor. img_4305.jpg The Friesen House is nearly 100 years old, and was on my parents property before it got moved to the Mennonite Heritage and Agricultural Museum. We were among maybe 20 people that showed up for the event. We walked in a few minutes early and Elvera was sitting at the organ already, along with a few other early arrivals. Many of the people there were over 70, and the moment we walked in, she said, Oh good! Another generation! And, of course, asked about us, where we live, who we are related to, etc. The announcement in our church bulletin said to bring a copy of Gesangbuch mit Noten if you have one. That was a common hymn book in Mennonite churches in Kansas (songbook with notes and yes, there was one without notes that had only words.) I pulled out my copy, and just opened it up. I saw my grandma s beautiful handwriting saying it belonged to Mr. and Mrs. R. A. Klassen . This I brought along, but was perhaps the only one. Elvera recognized it and was pleased to hear where it came from. We had a great time, and it turned out to feel like the kind of afternoon people around here used to have: time with friends and family visiting and maybe singing on occasion. After some introduction and some stories, we got to the singing and started with hymn #1 in the 1969 (English) Mennonite Hymnal. That song had German words below as well, which we sang: Grosser Gott, wir loben dich! (Holy God, We Praise Thy Name) Elvera played the organ while we all sang. And then we turned to #556, O Have You Not Heard. We read through the German lyrics (to help those that don t speak German):
Ich weiss einen Strom, dessen herrliche Flut
fliesst wunderbar stille durchs Land,
doch strahlet und gl nzt er wie feurige Glut,
wem ist dieses W sser bekannt? O Seele, ich bitte dich: Komm!
Und such diesen herrlichen Strom!
Sein Wasser fliesst frei und m chtiglich,
o glaub s, es fliesset f r dich!
Elvera translated this herself, a much more powerful translation than we usually get in English. And then we sang, this time a cappella. Elvera told the story about the train station to this group, and then, of course, we sang O Power of Love, one of the songs sung on that occasion. For that, she asked us to stand up and form a circle around the organ, and again we sang mostly a cappella. Singing that song with Elvera left few dry eyes in the room for sure. Someone brought up Nun Ist Sie Erschienen, and so of course we sang that. It wasn t in any hymnal, but I suspect we were the only ones there that didn t have it completely memorized. Elvera told us the story of the museum s pump organ; it had been in her family, and she had paid to have it restored and eventually donated it to the museum. It had been used every evening at twilight for singing and devotions in the family. She also told us that the singing at the Newton train station the same one our family uses a few times a year was what inspired her to a career of choral music. In the end, we probably spent more time visiting than singing, but that was just fine. Next the group went over to the Preparatory School, an old schoolhouse also on the museum grounds. There we had a traditional Faspa, an afternoon meal with coffee, Zwieback and jam, cheese, and various cookies. We all visited for awhile longer and then went on our way. It was a wonderful afternoon, and I hope to have a chance to do that sort of thing again.

10 October 2010

Gregor Herrmann: RC bugs 2010/40

a rather active week, although most of my uploads were (again!) either packages prepared by others or packages where I just applied existing patches from the BTS. in case you haven't seen it yet: there will be a BSP at the Mini DebConf Paris at the end of october. .

9 October 2010

Alastair McKinstry: Tidally locked Benchmarks

Fresh up on arxiv.org is a paper by Kevin Heng, Kristen Menou and Peter Phillipps: Atmospheric circulation of tidally-locked exoplanets: a suite of benchmark tests for dynamical solvers. Kristen Menou was at exoclimes 2010 where one of the background topics was how to compare and validate our various models in exoplanetary climates. Earth-based climate modellers have test cases such as Held-Suarez which are used to compare the models, but to date no equivalents are used for exoplanetary models. This work fills that gap for Tidally-locked atmospheres (similar to Zarmina for example, and some 'Hot Jupiters'. I'm particularly interested in the tidally-locked Earth case; it's relevant for my own PhD work. Incidentally, for a good summary of the different ways we test climate models, see Steve Easterbrook's recent blog entry; he's been doing a tour of major modelling centres, learning how they do things. Worth a look. Tags , ,

7 October 2010

Patrick Schoenfeld: FAI and custom packages

In the last two cases where I created FAI configurations for different systems I needed to install packages which are not part of the Debian repositories.
Unfortunately FAI does not provide a standard way to supply the installation with custom packages so I need to figure out a way on my own.

I have the following requirements in the solution:
It would be easy if a repository reachable by the installed system would already exist. Unfortunately it does not. But.. aha! So here is the idea:

  1. In the FAI configuration space add a new directory
    'packages'
  2. We will use reprepro for the repositiory. You should install it where ever you prepare the configuration space. It would also be an option to install it into the NFSROOT and run it from there, but I decided to pre-prepare it (but this would be a clean solution if one of the FAI developers decided to implement a standard way, I guess).
  3. Create a directory packages/conf and therein a file distribution with this content:
    Origin: Debian
    Label: Debian-All
    Suite: stable
    Codename: lenny
    Version: 5.0
    Architectures: i386 amd64
    Components: main
    Description: Debian Lenny
    Obviously you should adapt at least the Architectures line to whatever you need. Otherwise adapt what you need.
  4. Now you can add packages, with reprepro includedeb lenny /path/to/debfile from within that directory, so cd to it, before.
    The result is, that the packages directory becomes a full-fledged Debian APT repository which can be used with apt by creating a line similar to the following:
    deb file:/var/lib/fai/config/packages lenny main contrib non-free
  6. And thats what we'll do. In order to make this happen before any software gets installed, we create a hook. It needs to be called instsoft.CLASS where CLASS is a class that is used for the fai install we are working on. It basically needs to contain something like (+ the usual shell script stuff):

    $ROOTCMD ainsl /etc/apt/sources.list "deb file:/var/lib/fai/config/packages lenny main contrib non-free"
    $ROOTCMD apt-get update
    This should add the repository the sources.list in the /target and run apt-get update.
Thats it. This should be all to make the repo available to the usual installation. That means if your package_config files contain packages which are only part of the custom repo they will now be able to be installed.

(This might probably not be a copy and paste howto. It just describes the rough steps needed to do and might contain errors. So don't blame me if it doesn't work 100% this way. ;-)

Tim Retout: More bug fixing

I've been mostly working on GnuCash the past few evenings. I added more info and a test case to Bug #593856, so that should fall into place soon. I turned my attention to ettercap this evening, and Bug #521857 - another easy one, just applying the updated patch. Except when I ran "lintian -F", I got: 
lintian -F /var/cache/pbuilder/result/ettercap_0.7.3-2.1_amd64.changes 
E: ettercap: binary-or-shlib-defines-rpath ./usr/sbin/ettercap /usr/lib
E: ettercap-gtk: binary-or-shlib-defines-rpath ./usr/sbin/ettercap /usr/lib
This led me to a Jan 2008 email from Raphael Geissert about packages defining RPATH on amd64. For now, I've rebuilt in an i386 chroot - I'd need some help making a full lintian run on amd64 if I were going to propose a mass bug-filing.

Raphaël Hertzog: The right way to remove an obsolete conffile in a Debian package

A conffile is a configuration file managed by dpkg, I m sure you remember the introductory article about conffiles. When your package stops providing a conffile, the file stays on disk and it s recorded as obsolete by the package manager. It s only removed during purge. If you want the file to go away, you have to remove it yourself within your package s configuration scripts. You will now learn how to do this right. When is that needed? dpkg errs on the side of safety by not removing the file until purge but in most cases it s best to remove it sooner so as to not confuse the user. In some cases, it s even required because keeping the file could break the software (for example if the file is in a .d configuration directory, and if it contains directives that are either no longer supported by the new version or in conflict with other new configuration files). What s complicated in rm ? So you want to remove the conffile. Adding an rm command in debian/postinst sounds easy. Except it s not the right thing to do. The conffile might contain customizations made by the administrator and you don t want to wipe those. Instead you want to keep the file around so that he can get his changes back and do whatever is required with those. The correct action is thus to move the file away in the prerm, to ensure it doesn t disturb the new version. At the same time, you need to verify whether the conffile has been modified by the administrator and remember it for later. In the postinst, you need to remove the file if it s unmodified, or keep it under a different name that doesn t interfere with the software. In many cases adding a simple .dpkg-bak suffix is enough. For instance, run-parts ignore files that contain a dot, and many other software are configured to only include files with a certain extension say *.conf. In the postrm, you have to remove the obsolete conffiles that were kept due to local changes and you should also restore the original conffile in case the upgrade obsoleting the conffile is aborted. Automating everything with dpkg-maintscript-helper Phewww that s a lot of things to do for a seemingly simple task. Fortunately everything can be automated with dpkg-maintscript-helper. Let s assume you want to remove /etc/foo/conf.d/bar because it s obsolete and you re going to prepare a new version 1.2-1 with the appropriate code to remove the file on upgrade. You just have to put this snippet in the 3 relevant scripts (preinst, postinst, postrm): 
if dpkg-maintscript-helper supports rm_conffile 2>/dev/null; then
    dpkg-maintscript-helper rm_conffile /etc/foo/conf.d/bar 1.2-1 -- "$@"
fi
You can avoid the preliminary test if you pre-depend on dpkg (>= 1.15.7.2) or if enough time has passed to assume that everybody has a newer version anyway. You can learn all the details in dpkg-maintscript-helper s manual page. I hope you found this article helpful. You can follow me on Identi.ca, Twitter and Facebook.
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John Goerzen: Why all the Obama hate?

I am really struggling with all this anti-Obama rhetoric, coming from both the right and the left. From where I sit, while he hasn t been perfect, he s accomplished quite a bit for us since he s been president. Consider: I don t get it. Liberals are claiming he s not doing enough, but look at what he s got to work with: Republicans filibustering just about everything in the Senate. I don t think that s Obama s fault. And the conservatives, as far as I can tell, are just yelling. I can t figure this out. They want to cut taxes, cut the deficit, and increase defense spending. Good luck with that.

6 October 2010

Daniel Kahn Gillmor: monkeysphere and distributed naming

Roland Mas writes an interesting article about decentralized naming, in which he says:
Monkeysphere aims at adding a web of trust to the SSL certificates system, but the CA chain problem seems to persist (although I must admit I'm not up to speed with the actual details).
Since i'm one of the Monkeysphere developers, i figure i should respond! Let me clarify that Monkeysphere doesn't just work in places where X.509 (the SSL certificate system) works. It works in other places too (like SSH connections). And I don't think that the CA chain problem that remains in Monkeysphere is anything like the dangerous mess that common X.509 usage has given us. I do think that at some level, people need to think about who is introducing them to other people -- visual or human-comprehensible representations of public key material are notoriously difficult to make unspoofable. On the subject of distributed naming: OpenPGP already allows distributed naming: every participant in the WoT is allowed to assert that any given key maps to any given identity. Duplicates and disagreements can exist just fine. How an entity decides to certify another entity's ID without a consensus global namespace is a tough one, though. If i've always been known as "John Smith" to my friends, and someone else has also been known as "John Smith" to his friends, our friends aren't actually disagreeing or in conflict -- it's just that neither of us has a unique name. The trouble comes when someone new wants to find "John Smith" -- which of us should they treat as the "correct" one? I think the right answer probably has to do with who they're actually looking for, which has to do with why they're looking for someone named "John Smith". If they're looking for John Smith because the word on the street is that John Smith is a good knitter and they need a pair of socks, they can just examine what information we each publish about ourselves, and decide on a sock-by-sock basis which of us best suits their needs. But if they're looking for "John Smith" because their cousin said "hey, i know this guy John Smith. I think you would like to argue politics over a beer with him", then what matters is the introduction. And OpenPGP handles that just fine -- if their cousin has only ever met a single John Smith, that's the right one. If their cousin has met several John Smiths, then the searcher would do well to ask their cousin some variant of "hey, do you mean John Smith or John Smith ", or even "do you mean the John Smith who Molly has met, or the one who Charles has met?" (assuming that Molly and Charles have each only certified one John Smith in common with the cousin, and not the same one as each other), or to get a real-time introduction to a particular John Smith, where his specific key is somehow recordable by the searcher for future conversations (or beer drinking). This is what we do in the real world anyway. We currently lack good UIs for doing this over the network, but the certification infrastructure is in place already. What we're lacking in infrastructure, though, is a way to have a distributed addressing. Roland's proposal was to publish addresses corresponding to cryptographic identities within some DNS zone, or in freenet or gnutella. Another approach (piggybacking on existing infrastructure) would be to include IP address information in the OpenPGP self-certification, so the holder of the name could claim exactly their own IP address. This could be distributed through the keyserver network, just like other updates are today, and it could be done simply and immediately with a well-defined OpenPGP notation. I'd be happy to talk to interested people about how to specify such a notation, and what possible corner cases we might run into. Drop a note here, or mail the Monkeysphere mailing list or hop onto #monkeysphere on irc.oftc.netTags: authentication, distributed naming, identity, monkeysphere

Russ Allbery: Review: Thinking in Java

Review: Thinking in Java, by Bruce Eckel
Publisher: Prentice Hall
Copyright: 2006
Printing: October 2009
ISBN: 0-13-187248-6
Format: Trade paperback
Pages: 1461
Thinking in Java has gone through multiple editions. This review is of the 4th edition, which is targetted at Java 5 (with some minor updates for Java 6, released as it was going to press). Prior to reading this book, I'd never written code from scratch in Java and had never learned anything about Java in a structured fashion. My CS degrees come before the era of ubiquitous Java; the most I'd ever done with the language was look over and make some minor fixes to code other people had written, using general programming knowledge. I choose this book as my introduction because I was looking for a ground-up introduction with good reviews and was avoiding books that contained a printed version of the Java library documentation. I can get that myself on-line. I kept a set of notes on my impressions of the Java language itself separately and will not get into that here. This is, instead, a review of Thinking in Java as a book and as a training tool for someone who wants to pick up the language. First off, this is a remarkably well-titled book, much more so than the typical programming language book. Eckel is not just teaching Java as one programming language among many. He tries hard to teach the reader to think in Java, with a lot of attention to idiomatic use of the language and natural ways to use its expressiveness. This is exactly what I was looking for I don't want to just write C or Perl in Java syntax and I was very satisfied with the result. The book is also very heavy on source code examples; this is much of the reason why it's 1,461 pages. Eckel illustrates everything with Java code, generally complete functioning short programs. Even exploratory musings and experiments are implemented as Java code. I don't think there's any significant thought in this book that isn't shown in both text and in explained Java code. Eckel has also clearly put significant effort into choosing good examples and designing his sample programs. I have some past (mild) experience with object-oriented design, and a lot of experience with higher-level system design, and I was satisfied and occasionally intrigued by the object structures and design tips that Eckel provides. He uses design pattern language heavily, but not in a confusing way, and he takes some time to explain typical design patterns and illustrate them repeatedly. This is a solid introduction to good object-oriented program design as well as an introduction to Java. One oddity of this book, though, is that Eckel introduces the language from the ground up, starting with syntax and basic types, and is very careful not to use any concepts before he introduces them. The result is a very thorough introduction to the Java language, but it means that it takes 900 pages (!) before Eckel introduces I/O and the possibility of writing a useful program based on just the information in the book. This is for entirely sound conceptual reasons: I/O in Java relies on lots of concepts, like exceptions and generics, that require extensive introduction and discussion. However, it does mean that through well more than half of a monumental tome the reader is learning the language through rather artificial programs. I have extensive prior programming background and a high tolerance for more abstract examples (I have a master's degree in software theory), so I could deal with this, but even with that background I was starting to feel like my head was getting too full and too crowded with concepts without being able to make them concrete. It probably would have helped to work through some of the exercises, but I dislike exercises that aren't grounded in some problem I personally want to solve. If you're someone who only learns languages through practical application, this approach to teaching the language may drive you nuts, and you may want to look for another book that compromises conceptual progression to get you started faster. Related to this, Thinking in Java is not about the standard library. It's about the language, and the vast majority of this book is focused directly on the language level: inheritance, information hiding, generics, exceptions, introspection, concurrency, annotations, serialization, and so forth. The only parts of the standard library that Eckel covers in depth are the container classes, I/O, and a somewhat odd and misplaced final chapter on Swing. There is nothing about databases, essentially nothing about web applications or containers, no network programming, and very little in the way of practical, applied problems. As you might guess from the combination of that limitation of scope and the length of this book, that means it is extremely comprehensive; I doubt there are many corners of the basic language semantics, including around generics, that Eckel leaves unexplored. This is exactly what I wanted (I know how to read library documentation myself and all language core libraries start looking mostly the same after you've programmed in five or six languages), but it's very different from the typical approach of a programming language book. Don't be surprised. This biggest problem with Thinking in Java from my perspective is that it defers many interesting topics to Eckel's web pages and to free companion books and material that is supposedly found there, to the point of advertising that on the cover. This is a good way to allow the reader to explore extra topics that are of specific interest while skipping others, provided that one actually delivers on that promise. However, Eckel's web site is dire. The first time I looked at it earlier this year I was unable to find most of the supplemental material the book promises is there, and now www.mindview.net doesn't resolve in DNS. I've found copies of some of that material hosted elsewhere in Google searches, but this is a rather frustrating experience if one was relying on that supplemental material to fill in the gaps. And the book is clearly written expecting people to go look at the web materials; Eckel refers to them probably a hundred times over the course of the book. Less of a serious problem, and more of a quirk, is the closing chapter on Swing. This chapter really doesn't fit much with the book. I suppose Eckel felt obligated to put in at least one chapter on some concrete applied topic (I personally would have preferred databases be that topic, but oh well), and it does serve a useful purpose in showing how concurrency, inner classes, inheritance, and introspection all work together in a significant Java library. But it's not presented as just an example, and it fits in oddly with the rest of the book. It also has an inexplicable middle section about Flash programming. I ended up mostly skimming this. But this isn't much of a flaw in the book; if one ignores 100 pages out of 1,450, that's not much of a loss. Eckel comes from a C++ background (he was a founding member of the C++ standardization committee), which shows up most prominantly in the generics chapter. It's a solid, thorough introduction to Java generics, but it also has an extensive exploration of all the problems with the Java erasure model and many, many examples of the things that one would find intuitive from C++ that don't work the same way in Java. If you come from a C++ background, this is quite possibly useful; if, like me, you don't care about C++, it's at best mildly interesting and gets a touch tedious. There are a few other places where Eckel pokes surprisingly sharp sticks at the Java designers, but taken in context I think this is a quirk of the book's conversational style (which is otherwise a feature). Eckel's love of Python is also somewhat entertaining (particularly the long advertisement for Python in the introductory chapters of a book on Java), but has little impact on the book. I think the largest drawback of it is that all the examples in this book are tested using a Python framework, which isn't so much a problem with them as a lost opportunity. They're annotated with metadata used by Eckel's Python test framework, and in a Java book I would have been much more interested in a good Java test framework built on top of something like JUnit. Oh well. Overall, this is a very solid book which, despite being enormous, does not feel pointlessly padded. It's thorough and exhaustive on its topic, but there's a point to nearly everything in here. It was also exactly the Java book I wanted: an introduction to the language, built on a firm foundation of object-oriented program design, with discussion and pointers on how to think idiomatically in the language and use it to its fullest potential, and without mindlessly reproducing the standard library documentation. If that's also what you're looking for in a Java book, I recommend it highly. Just know going in what sort of book you're getting, since its pacing and order of presentation may frustrate some learning styles. Rating: 8 out of 10

Michal Čihař: Making Gammu use GLib

I had this topic in mind for quite a long time, but it got more recently more attention because of discussions on gammu-users mailing list. Gammu should use some library for do basic stuff like strings or date manipulations, logging and so on. The reason is that having own implementation of all that is not really useful and just source of another amount of bugs. Currently mi intention is to use GLib, simply because I don't know any C alternative (though there are probably lot of C++ cross platform libraries). Of course the biggest question is how to make the change, because it will be obviously intrusive and making such big changes will probably lead to several months of work without really making another release. Even if it will be done on separate branch (what would be most likely the case), developers will spend most of time on this issue and not much time will be spent on bug fixes (and backporting them).

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Roland Mas: Automounting a LUKS-encrypted USB key

You have a computer. You're afraid of it being stolen by baddies or raided by the police, so you've encrypted its hard disk with LUKS. You also want to carry around some of your crypto keys (SSH and/or GPG), or any kind of sensitive data, on an USB key, so you can restore a normal activity in case the computer gets stolen or becomes untrustworthy. You like things that Just Work, including automounting with autofs (no GUI popups, no need to manually unmount and so on). But of course, you can't very well just mount the drive and store your keys on it in the clear. Well, actually you can (I did it for way too long), but let's assume you want to do without. Because USB keys get stolen or lost, too. autofs just handles the mounting of the drives, not their unlocking, and there's no hook in there specifically for LUKS. There is, however, a more generic way of running arbitrary commands on mounting: the program maps. It's all described in the documentation, so I'll just paste the relevant parts of my /etc/auto.removable, with a few comments. Remember to make it executable and reference it in /etc/auto.master. 
 #! /bin/sh
 volume=$1
 autoluks ()  
   dev=/dev/$1
   cryptname=$ 1 _crypt
   cryptdev=/dev/mapper/$cryptname
   keyfile=/etc/private/$cryptname.key
   options=$2
   [ ! -e $dev ] && exit 0
   if [ -b $cryptdev ] && ! cryptsetup status $cryptname   grep -q device:.*$dev ; then
       cryptsetup remove $cryptname   logger
   fi
   cryptsetup --key-file $keyfile luksOpen $dev $cryptname   logger
   [ -b $cryptdev ] && echo $options :$cryptdev   true
  
 case "$volume" in
   # LUKS-encrypted volumes
   lacie-keys)
       autoluks lacie-keys -fstype=ext4,ro,noatime,nodev,noexec,nosuid
       ;;
   lacie-keys-rw)
       autoluks lacie-keys -fstype=ext4
       ;;
   lacie-backups)
       autoluks lacie-backups -fstype=ext4
       ;;
   # Non-encrypted volumes
   cd)
       echo -fstype=iso9660,ro,nodev,nosuid            :/dev/cdrom
       ;;
   floppy)
       echo -fstype=auto,sync,nodev,nosuid             :/dev/fd0
       ;;
 esac
The astute reader will have noticed that the keys volume is mounted either read-only or read-write with the same mechanism. This volume contains SSH keys that I use quite regularly, that filesystem is going to be mounted and unmounted very often. USB keys, and flash memory in general, don't really like repeated writes. Fortunately, the SSH keys are mostly read, and very rarely written to, so I can afford to mount the partition read-only and save the write cycles for when I generate new keys (the mere action of mounting a partition read-write changes it, even if the files in it are never modified). The backups volume is mostly accessed in write mode, and much less frequently anyway, so there's no need for a distinction there. This supposes that the partitions on the USB key appear as /dev/lacie-keys and /dev/lacie-backups. Due to the dynamic naming of devices, you may like to use rules similar to the following in /etc/udev/rules.d/local. 
 KERNEL=="sd[a-z]1", ATTRS idProduct =="1027", ATTRS idVendor =="059f", ATTRS manufacturer =="LaCie", ATTRS product =="LaCie iamaKey", SYMLINK+="lacie-keys"
 KERNEL=="sd[a-z]2", ATTRS idProduct =="1027", ATTRS idVendor =="059f", ATTRS manufacturer =="LaCie", ATTRS product =="LaCie iamaKey", SYMLINK+="lacie-backups"
You'll also need to initialize LUKS on the partitions, save the key, make the filesystems, and so on. If you're still with me, you probably know what I'm talking about, then I don't need to explain about that. This setup works for me, but there's no guarantee and so on. Based on a tutorial found on the Debian Administration website (great resource, by the way). Update: I'm told a large part of the script could be replaced with pmount. If you like short scripts, you may want to investigate that too. Update 2: Josselin points out a different solution using Gnome, udisks, gnome-disk-utility and Nautilus. It's worth checking out, for those who like to run all that and click around. I can't test it right now (Gnome/Nautilus currently refuses to mount any USB key, for some presumably transitional reason), but I have no reason to believe it's inherently broken. I just don't like having to do anything when I plug my key or before I unplug it, and I'm not always running a graphical session with a desktop.

5 October 2010

Gerfried Fuchs: New Backports Suite created

The Backports Team is pleased to announce the availability of a new suite on backports: lenny-backports-sloppy. Please read carefully before considering using or uploading to it what this entails. The Background You might want to ask: What's that? Let me explain it. During the etch release discussions popped up on the backports list with two clashing groups: The standing at that time was to accept packages that were in testing after the release, which wasn't etch anymore but lenny. The same discussion started again before the lenny release, and given that we are facing the upcoming squeeze release we started internally to discuss how to noise down these long and tedious discussions, because both groups of people had valid opinions that shouldn't get ignored. So this is where the idea for lenny-backports-sloppy comes from. The Change lenny-backports-sloppy will please the group that is happy to upgrade from lenny + lenny-backports to squeeze + squeeze-backports. lenny-backports is meant only for packages from squeeze, even after the release. Technically that means it will get locked down for uploads after the release of squeeze and require manual approval (for e.g. point release update versions, or security updates that happen during the squeeze release cycle), while lenny-backports-sloppy will accept packages from wheezy. Uploading to lenny-backports will have to get approved by the Debian Backports Team after the squeeze release, just like uploads to lenny are currently approved by the Release Team. While lenny-backports-sloppy is created already and working we ask you to not upload packages there without prior discussion with the Backports Team. This is meant to ensure that the Uploader is aware about the expectations that come along with that: The package should have a good chance to get included in the next Debian release aka wheezy, and that the Uploader is willing to look after the package in the upcoming squeeze-backports suite after the release of squeeze to ensure upgradability. In case of questions, feel free to ask either directly on the debian-backports@lists.debian.org mailinglist, or contact team@backports.debian.org privately. We are also pleased to announce that the first upload to lenny-backports-sloppy already happened. From now on you will be able to install Postgresql 9.0 (which is not targeted at squeeze) from lenny-backports-sloppy. How to use If you want to use lenny-backports-sloppy you will have to add both lenny-backports and lenny-backports-sloppy to your sources.list. Backports from lenny-backports-sloppy may depend on packages in lenny-backports. 
  deb http://backports.debian.org/debian-backports lenny-backports   main
  deb http://backports.debian.org/debian-backports lenny-backports-sloppy main
About Backports You are running Debian stable, because you prefer the stable Debian tree. It runs great, there is just one problem: the software is a little bit outdated compared to other distributions. That is where backports come in. Backports are recompiled packages from testing (mostly) and unstable (in a few cases only, e.g. security updates), so they will run without new libraries (wherever it is possible) on a stable Debian distribution. It is recommended to pick out single backports which fit your needs, and not to use all available backports. Thanks for reading this far, and enjoy!
Rhonda in the name of the Backports Team

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Alexander Wirt: A new player in the house: lenny-backports-sloppy

The Backports Team is pleased to announce the availability of a new
suite on backports: lenny-backports-sloppy. Please read carefully
before considering using or uploading to it what this entails.
The Background You might want to ask: What's that? Let me explain it. During the etch
release discussions popped up on the backports list with two clashing
groups: The standing at that time was to accept packages that were in testing
after the release, which wasn't etch anymore but lenny. The same discussion started again before the lenny release, and given that
we are facing the upcoming squeeze release we started internally to discuss
how to noise down these long and tedious discussions, because both groups
of people had valid opinions that shouldn't get ignored. So this is where
the idea for lenny-backports-sloppy comes from.
The Change lenny-backports-sloppy will please the group that is happy to upgrade from
lenny + lenny-backports to squeeze + squeeze-backports. lenny-backports is
meant only for packages from squeeze, even after the release. Technically
that means it will get locked down for uploads after the release of squeeze
and require manual approval (for e.g. point release update versions, or
security updates that happen during the squeeze release cycle), while
lenny-backports-sloppy will accept packages from wheezy. Uploading to
lenny-backport will have to get approved by the Debian Backports Team after
the squeeze release, just like uploads to lenny are currently approved by
the Release Team. While lenny-backports-sloppy is created already and working we ask you to
NOT upload packages there without prior discussion with the Backports Team.
This is meant to ensure that the Uploader is aware about the expectations
that come along with that: The package should have a good chance to get
included in the next Debian release aka wheezy, and that the Uploader is
willing to look after the package in the upcoming squeeze-backports suite
after the release of squeeze to ensure upgradeability. In case of questions, feel free to ask either directly on the
debian-backports@lists.debian.org mailinglist, or contact
team@backports.debian.org privately. We are also pleased to annonce that the first upload to
lenny-backports-sloppy already happened. From now on you will be able
to install Postgresql 9.0 (which is not targeted at squeeze) from
lenny-backports-sloppy.
How to use If you want to use lenny-backports-sloppy you will have to add both
lenny-backports and lenny-backports-sloppy to your sources.list. Backports
from lenny-backports-sloppy may depend on packages in lenny-backports.
deb http://backports.debian.org/debian-backports lenny-backports main
deb http://backports.debian.org/debian-backports lenny-backports-sloppy main

4 October 2010

Tim Retout: Warn your distributor

My gnucash fix from last night poses an interesting problem - there will be no new gnucash 2.2.x release. So we can fix this potential data loss bug in Debian (probably even in lenny), but what about other distributions? I'm not aware of a formal way to co-ordinate non-security patches like this across distros. (Sure, we can leave it for the vultures on the patch tracker...) Someone should whip up a whizzy web-app, or whatever.

Raphaël Hertzog: Can Debian offer a Constantly Usable Testing distribution?

Debian s testing distribution is where Debian developers prepare the next stable distribution. While this is still its main purpose, many users have adopted this version of Debian because it offers them a good trade-off between stability and freshness. But there are downsides to using this distribution and the Constantly Usable Testing (CUT) project aims to resolve those. This article will present the project and the challenges involved to make it happen. About Debian unstable & testing Debian unstable is the distribution where developers upload new versions of their packages. It happens frequently that some packages are not installable due to changes in other packages or due to transitions not yet completed. Debian testing, on the contrary, is managed by a tool that ensures the consistency of the whole distribution: it picks updates from unstable only if the package has been enough tested (10 days usually), if it s free of new release-critical bugs, if it s available on all supported architectures, and if it doesn t break any other package already present in testing. The Release Team (RT) controls this tool and provide hints to help it find a set of packages that can flow from unstable to testing. Those rules also ensure that the packages that flow into testing are reasonably free of show-stopper bugs (like a system that doesn t boot, or X that doesn t work at all). This makes it very attractive to users who like to regularly get new upstream versions of their software without dealing with the biggest problems associated to them. This is all very attractive, yet several Debian developers advise people to not use testing. Why is that? Known problems with testing Disappearing software The release team use this distribution to prepare the next stable release and from time to time they remove packages from it. Either because it s needed to ensure that other packages can migrate from unstable to testing, or because they have long-standing release-critical bugs without progress towards a resolution. It also happens that they remove packages on request of the maintainers because they believe that the current version of the software cannot be supported (security-wise) for 2 years or more. The security team also regularly issues such requests. Long delays for security and important fixes Despite the 10-day delay in unstable, there are always some annoying bugs (and security bugs are no exceptions) that are only discovered when the package already has migrated to testing. The maintainer might be quick to upload a fixed package in unstable, and might even raise the urgency to allow the package to migrate sooner, but if the packages gets entangled in a large ongoing transition, it will not migrate before the transition is completed. Sometimes it can take weeks for that to happen. This delay can be avoided by doing direct uploads to testing (through testing-proposed-updates) but this is almost never used, except during a freeze, where targeted bugfixes are the norm. Not always installable With testing evolving daily, updates sometimes break the last installation images available (in particular netboot images that get everything from the network). The debian-installer (d-i) packages are usually quickly fixed but they don t move to testing automatically because the new combination of d-i packages has not necessarily been validated yet. Colin Watson sums up the problem:
Getting new installer code into testing takes too long, and problems remain unfixed in testing for too long. [...] The problem with d-i development at the moment is more that we re very slow at producing new d-i *releases*. [...] Your choices right now are to work with stable (too old), testing (would be nice except for the way sometimes it breaks and then it tends to take a week to fix anything), unstable (breaks all the time).
CUT s history CUT finds its root in an old proposal by Joey Hess: it introduces the idea that the stable release is not Debian s sole product and that testing could become with some work a suitable choice for end-users. Nobody took on that work and there was no visible progress in the last 3 years. But recently Joey brought up CUT again on the debian-devel mailing list and Stefano Zacchiroli (the Debian project leader) challenged him to setup a BoF on CUT for Debconf10. It turned out to be one of the most heavily attended BoF (video recording is here), there is clearly a lot of interest in the topic. There s now a dedicated wiki and an Alioth project with a mailing list. The rest of this article tries to summarize the various options discussed and how they re supposed to address the problems identified. The ideas behind CUT Among all the ideas, there are two main approaches that have been discussed. The first is to regularly snapshot testing at points where it is known to work reasonably well (those snapshots would be named cut ). The second is to build an improved testing distribution tailored to the needs of users who want a working distribution with daily updates, its name would be rolling . Regular snapshots of testing There s general agreement that regular snapshots of testing are required: it s the only way to ensure that the generated installation media will continue to work until the next snapshot. If tests of the snapshot do not reveal any major problem, then it becomes the latest cut . For clarity, the official codename would be date based: e.g. cut-2010-09 would be the cut taken during September 2010. While the frequency has not been fixed yet, the goal is clearly to be on the aggressive side: at the very least every 6 months, but every month has been suggested as well. In order to reach a decision, many aspects have to be balanced. One of them (and possibly the most important) is the security support. Given that the security team is already overworked, it s difficult to put more work on their shoulders by declaring that cuts will be supported like any stable release. No official security support sounds bad but it s not necessarily so problematic as one might imagine. Testing s security record is generally better than stable s one (see the security tracker) because fixes flow in naturally with new upstream versions. Stable still get fixes for very important security issues sooner than testing, but on the whole there are less known security-related problems in testing than in stable. Since it s only a question of time until the fixed version comes naturally from upstream, more frequent cut releases means that users get security fixes sooner. But Stefan Fritsch, who used to be involved in the Debian testing security team, has also experienced the downside for anyone who tries to contribute security updates:
The updates to testing-security usually stay useful only for a few weeks, until a fixed version migrates from unstable. In stable, the updates stay around for a few years, which gives a higher motivation to spend time on preparing them.
So if it s difficult to form a dedicated security team, the work of providing security updates comes back to the package maintainer. They are usually quite quick to upload fixed packages in unstable but tend to not monitor whether the packages migrate to testing. They can t be blamed because testing was created to prepare the next stable release and there is thus no urgency to get the fix in as long as it makes it before the release. CUT can help in this regard precisely because it changes this assumption: there will be users of the testing packages and they deserve to get security fixes much like the stable users. Another aspect to consider when picking a release frequency is the amount of associated work that comes with any official release: testing upgrades from the previous version, writing release notes and preparing installation images. It seems difficult to do this every month. With this frequency it s also impossible to have a new major kernel release for each cut (since they tend to come out only every 2 to 3 months) and the new hardware support that it brings is something worthwhile to many users. In summary, regular snapshots address the not always installable problem and changes the perception of maintainers towards testing, so that hopefully they care more of security updates in that distribution (and in cuts). But they do not solve the problem of disappearing packages. Something else is needed to fix that problem. A new rolling distribution? Lucas Nussbaum pointed out that regular snapshots of Debian is not really a new concept:
How would this differentiate from other distributions doing 6-month release cycles, and in particular Ubuntu, which can already be seen as Debian snapshots (+ added value)?
In Lucas s eyes, CUT becomes interesting if it can provide a rolling distribution (like testing) with a constant flux of new upstream releases . For him, that would be something quite unique in the Free Software world . The snapshots would be used as starting point for the initial installation, but the installed system would point to the rolling distribution and users would then upgrade as often as they want. In this scenario, security support for the snapshots is not so important, what matters is the state of the rolling distribution. If testing were used as the rolling distribution, the problem of disappearing packages would not be fixed. That s why there have been discussions of introducing a new distribution named rolling that would work like testing but with adapted rules, and the cuts would then be snapshots of rolling instead of testing. The basic proposal is to make a copy of testing and to re-add the packages which have been removed because they are not suited for a long term release while they are perfectly acceptable for a constantly updated release (the most recent example being Chromium). Then it s possible to go one step further: during freeze, testing is no longer automatically updated which makes it inappropriate to feed the rolling distribution. That s why rolling would be reconfigured to grab updates from unstable (but using the same rules than testing). Given the frequent releases, it s likely that only a subset of architectures would be officially supported. This is not a real problem because the users who want bleeding edge software tends to be desktop users on mainly i386/amd64 (and maybe armel for tablets and similar mobile products). This choice if made opens up the door to even more possibilities: if rolling is configured exactly like testing but with only a subset of the architectures, it s likely that some packages migrate to rolling before testing when non-mainstream architectures are lagging in terms of auto-building (or have toolchain problems). While being ahead of testing can be positive for the users, it s also problematic on several levels. First, managing rolling becomes much more complicated because the transition management work done by the release team can t be reused as-is. Then it introduces competition between both distributions which can make it more difficult to get a stable release out, for example if maintainers stop caring of the migration to testing once the migration to rolling has been completed. The rolling distribution is certainly a good idea but the rules governing it must be designed to avoid any conflict with the process of releasing a stable distribution. Lastly, the mere existence of rolling would finally fix the marketing problem plaguing testing: the name rolling does not suggest that the software is not yet ready for prime time. Conclusion Whether CUT will be implemented remains to be seen, but it s off for a good start: ftpmaster Joerg Jaspert said that the new archive server can cope with a new distribution, and there s now a proposal shaping up. The project might start quickly: there is already an implementation plan for the snapshot side of the project. The rolling distribution can always be introduced later, once it is ready. Both approaches can complement each other and provide something useful to different kind of users. The global proposal is certainly appealing: it would address the concerns of obsolescence of Debian s stable release by making intermediary releases. Anyone needing something more recent for hardware support can start by installing a cut and follow the subsequent releases until the next stable version. And users who always want the latest version of every software could use rolling after having installed a cut. From a user point of view, there are similarities with the mix of usual and long term releases of Ubuntu. But from the development side, the process followed would be quite different, and the constraints imposed by having a constantly usable distribution are stronger: any wide-scale change must be designed in a way that it can happen progressively in a transparent manner for the user.
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Jonny Lamb: Automatic Connections

My network blocks SIP on 3G, so when I start using its 3G service after leaving a wireless network my N900 goes absolutely crazy about not being to connect. Although this is a specific annoyance I have, it's a general problem with loads of similar cases, such as "I only want my work jabber/skype/MSN/etc. account enabled when I'm at work". So, I wrote a small daemon and a fun UI to make this easy. It's actually really simple: once you configure which connections accounts should listen for, it uses libconic to listen for connect/disconnect events and enables and disables accounts as appropriate. You should also be able to override its actions temporarily without it clobbering your setting. Click for full-sized image
A sneaky peek at the UI. See if you can guess where I've been visiting recently. I think the UI is pretty easy to use, and should cover most use cases. I just uploaded it to extras-devel. It's called Automatic Connections.

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