Search Results: "ag"

16 October 2010

Bastian Venthur: Introducing python-popcon

Python-popcon is a small Python library which allows to query Debian s popcon database. The usage is very trivial:
>>> import popcon
>>> popcon.package('python-popcon')
'python-popcon': 2 >>> popcon.package('icedove', 'iceweasel')
'icedove': 12140, 'iceweasel': 45666
>>> popcon.package('foobarbaz')

You can call the package method with an arbitrary number of package names and it will return a dictionary with package name : popcon value mappings for all packages found. If a package is not found in the popcon database it will not be in the resulting dictionary or if it was the only package in the method call, the method will return an empty dictionary. The popcon value is the number of installations according to Debian s Popularity Contest service. There is also a second method which gives some more information
>>> popcon.package_raw('icedove', 'iceweasel')
'icedove': [8065, 2195, 1879, 1], iceweasel : [27857, 10681, 7120, 8]
It returns a list of [vote, old, recent, no-files] for the given package. How does it work? Upon a query, popcon downloads http://popcon.debian.org/all-popcon-results.txt.gz, extracts and parses the file and returns the desired information. Since downloading and extraction this file is expensive, it saves the file and tries to re-use it is not older than 7 days. So while the first call of one of the above methods can take a few seconds, the result will appear almost instantaneously for the next week until the cache file expired. That s it, no rocket science but a convenient way to get popcon information from within python. The package python-popcon is available in Debian/Sid for a few days.

Ingo Juergensmann: Upgrading to Squeeze - and suddenly CGI doesn't work anymore

Before I upgraded from Lenny to Squeeze, all my CGI scripts were working properly. The CGI scripts has been executed by Apache and resulted in rendered webpage. After the upgrade to Squeeze all those CGI scripts stopped been executed but instead started to get displayed as a plain text. Common to all those CGI scripts is that they have .phtml as suffix, but the bang path/shebang consists of "#!/usr/bin/python". As an example you can have a look at Buildd.Net and its scripts like this one. The section in Apaches config looks like this:
<Directory /home/builddnet/unstable/WWW/cgi/>
Options -Indexes +ExecCGI +FollowSymLinks
AddHandler cgi-script .cgi .sh .pl .py .phtml
Order allow,deny
Allow from all
</Directory>
So, I would expect that the CGI script handler will get executed when loading a *.phtml file and that the shebang would be honoured. Funny enough: when I rename that script to *.cgi it works. I haven't figured out yet, what causes this beahviour or what have changed during the upgrade - and how to revert to the old behaviour. So, dear lazyweb, can you give me some hints and pointers?

Siegfried Gevatter: Debious A dubious Debian packaging GUI

Just some little (unfinished) concept mockup. Seeing that much of it still ends up as a text box with syntax highlighting it d probably make sense to implement it as a gedit plugin.

Balsamiq source XML Related posts:

  1. One week with Debian
  2. Packaging: Test-building your packages
  3. Arreglant paquets que no compilen: necpp

8 comments
Siegfried-Angel Gevatter Pujals, 2010. Permalink License Post tags: , ,

Pietro Abate: hidden ssh service via tor

We live in a nat-ed / firewall-ed world. Almost all DSL providers don't give public IPs and when the do, they are often behind a draconian firewall. In this context having an emergency remote shell, despite not fast and not public is very handy. A simple way to solve this problem it to create a hidden server on the tor network and the access the shell from anywhere in the world without caring of change of IPs, routing, dns or anything else. On debian you can just install tor from the official repository. Since Tor is not available in ubuntu (but it is available on debian), we need to get it directly from the tor website. There is a nice write-up on the ubuntu site : https://help.ubuntu.com/community/Tor . And these are the details on the tor website. So we add this to apt.sources
deb http://deb.torproject.org/torproject.org lucid main
and the we aptitude install tor .The package will install and run by default the tor daemon. Next step is to edit /etc/tor/torrc to add the proxy server.
HiddenServiceDir /var/lib/tor/ssh/
HiddenServicePort 22 127.0.0.1:22
Remember also to install the openssh-server server if you don't have it already. And this is it. In the directory /var/lib/tor/ssh/ you will find a file with the hostname on the TOR ring that you have to use to connect to you new hidden server. On the client side we need to aptitude install connect-proxy. It's a simple tool to tunnel ssh through a socks5 connection. Now you are ready to test. In your ~/.ssh/config you can simply add something like
Host *.onion
ProxyCommand connect -R remote -5 -S 127.0.0.1:9050 %h %p
and then ssh-way youronionhost.onion server . The connection will be veeeeery slow since you are going through different layers of encryption and indirection. You should also check the hostid of your server before connecting and dropping in a pub-key as you should never trust your friendly TOR providers (US govt, Chinese gvt, Iranian govt, etc ...). For emergency is actually pretty handy. For anything else if will make you die of boredom ...

Update Ahhh . It seems I've assumed that since TOR was not available on ubuntu, this was the same on debian. Tor is definitely available on debian, but not on ubuntu. Blah... check before asserting wrong information ! Post fixed.

Martin-&#201;ric Racine: Batch-editing EXIF data to add copyrights?

I've recently become more serious about my photographic hobby and it dawned onto me that manually editing each JPEG to add my copyright was entirely the wrong approach. Thus, I was wondering if anybody would know of a Free Software tool that can batch edit the EXIF data in JPEG images? What I'd like to accomplish is simple: Preferences go for a tool that is already packaged for Debian or Ubuntu but, worst comes, I could package the software myself.

Vincent Sanders: Coming to terms

Yesterday was not a great day. One of the family's cats died.

Molly just after she arrived 26th September 2000
Molly, for that was her name, came to us the week Melodie and I moved into our first house together. September 15th 2000, in the middle of the fuel protests which were raging at the time, we hired a van and moved in.

Most people would have considered that enough for one week! We happened to be in Halifax on the Sunday afternoon at the supermarket and decided to visit the RSPCA because somehow we decided what our new home needed was a cat.

On that day a decade ago we saw Molly and Lucy, a pair of cats who needed a new home as their previous owners had a baby who was allergic to them. I still recall them skulking at the back of their cage in the cattery, Lucy who was reluctant to come down of a perch to be petted and Molly looking generally unhappy. No-one else wanted this misfit pair because they were already both over 5 years old, the warden despairing of ever finding them a home.

Of course they were obviously the right animals for us! ;-) So by the end of the week we had taken them home. Molly immediately showed how things were going to be by shredding her way out of the RSPCA provided double walled cardboard carrier. To the day she died she detested being placed inside a carrier, funny that.

Melodie and Molly in the snow 28th December 2000
By the end of the year, when the snow came, the cats ruled the house and we were all happy together.

Little did we realise that soon in the summer of 2001 there would be another arrival to the family.

Molly with Melodie and Alex 2001
The arrival of our first child in June 2001 was a complete change in all our lives but we all managed to settle back into a routine. Although the banishment of the cats from upstairs remained a point of disagreement for a long time.

As Alex grew up the cats learned that feeding times for Alex could result in all manner of things falling from above. Soon Alex was mobile which resulted in different lessons on cats being sharp objects if not treated with respect. In February 2003 our family grew once more with the arrival of Joshua. The cats, now used to infants, took this in their stride.

Molly in Febuary 2004 hiding on a windowsill
While still about day to day the cats are not captured on camera so often form this point on.

Over the forthcoming months they ensured they were out of reach of the newborn and the precocious toddler.

By the time of Joshuas first birthday in 2004 Molly had taken to hiding "out of the way" as much as possible but remained as affectionate as ever.

Molly in a box March 2007
As the children grew up and life progressed Molly became ever more at home and developed the odd aggravating trait like taking clean washing off airers and dragging it out the window, through the cat flap and upstairs so she could sleep on it!

She still enjoyed participating in claiming boxes and defending them vigorously though!

The kids took on the job of feeding the cats which made their bond closer ensuring they were greeted by happy cats sitting lookout as they came home from school each day.

Molly continued to be a good companion and an infuriating self centred animal like all good cats.
Molly asleep in the kitchen sink
Then on Tuesday evening our Neighbour knocked on our front door. They gave us the news that one of our cats had been run over and taken to the Vet. I immediately went to the back door and called and shook the treat box.

Lucy came running, but molly did not. We rang the vets who confirmed they had molly (we had them electronically tagged back in Halifax) and that they advised we did not come and see her until they had chance to asses her and deal with the shock.

As the days progressed her prognosis improved and then sank. She had a broken jaw, broken teeth, a dislocated hip, extensive bruising and something was definitely wrong with her kidney function.

Thursday evening the whole family went to see her and she purred and seemed happy to see us, she looked as bad as I feared though and somehow I knew there and then that this was probably goodbye. The children stroked her and petted her for a while and we left with an odd sadness, oh and to the sound of molly trying to gouge the veterinary nurse.

Yesterday she was due to have surgery to fix her jaw and hip...Alas when she was anaesthetised and x-rayed once more it became evident the hip was not just dislocated but her femur was fractured and there was additional damage. So just after midday came the call to ask what we wanted to do. The vet could attempt the repairs but due to her age and the other complications it was probably futile. So with heavy heart we agreed the best thing was not to revive her and she died a short time later.

I shall miss her morning greetings, her demands for attention, her sleeping in odd places and her companionship. I keep calling for her at meal times forgetting she will never come. I think Lucy is upset too, after spending their lives together her friend is gone and I cannot explain that to her.

So that is the end of Molly, a good cat.


15 October 2010

Enrico Zini: Award winning code

Award winning code Me and Yuwei had a fun day at hhhmcr (#hhhmcr) and even managed to put together a prototype that won the first prize \o/ We played with the gmp24 dataset kindly extracted from Twitter by Michael Brunton-Spall of the Guardian into a convenient JSON dataset. The idea was to find ways of making it easier to look at the data and making sense of it. This is the story of what we did, including the code we wrote. The original dataset has several JSON files, so the first task was to put them all together:
#!/usr/bin/python
# Merge the JSON data
# (C) 2010 Enrico Zini <enrico@enricozini.org>
# License: WTFPL version 2 (http://sam.zoy.org/wtfpl/)
import simplejson
import os
res = []
for f in os.listdir("."):
    if not f.startswith("gmp24"): continue
    data = open(f).read().strip()
    if data == "[]": continue
    parsed = simplejson.loads(data)
    res.extend(parsed)
print simplejson.dumps(res)
The results however were not ordered by date, as GMP had to use several accounts to twit because Twitter was putting Greather Manchester Police into jail for generating too much traffic. There would be quite a bit to write about that, but let's stick to our work. Here is code to sort the JSON data by time:
#!/usr/bin/python
# Sort the JSON data
# (C) 2010 Enrico Zini <enrico@enricozini.org>
# License: WTFPL version 2 (http://sam.zoy.org/wtfpl/)
import simplejson
import sys
import datetime as dt
all_recs = simplejson.load(sys.stdin)
all_recs.sort(key=lambda x: dt.datetime.strptime(x["created_at"], "%a %b %d %H:%M:%S +0000 %Y"))
simplejson.dump(all_recs, sys.stdout)
I then wanted to play with Tf-idf for extracting the most important words of every tweet:
#!/usr/bin/python
# tfifd - Annotate JSON elements with Tf-idf extracted keywords
#
# Copyright (C) 2010  Enrico Zini <enrico@enricozini.org>
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
import sys, math
import simplejson
import re
# Read all the twits
records = simplejson.load(sys.stdin)
# All the twits by ID
byid = dict(((x["id"], x) for x in records))
# Stopwords we ignore
stopwords = set(["by", "it", "and", "of", "in", "a", "to"])
# Tokenising engine
re_num = re.compile(r"^\d+$")
re_word = re.compile(r"(\w+)")
def tokenise(tweet):
    "Extract tokens from a tweet"
    for tok in tweet["text"].split():
        tok = tok.strip().lower()
        if re_num.match(tok): continue
        mo = re_word.match(tok)
        if not mo: continue
        if mo.group(1) in stopwords: continue
        yield mo.group(1)
# Extract tokens from tweets
tokenised = dict(((x["id"], list(tokenise(x))) for x in records))
# Aggregate token counts
aggregated =  
for d in byid.iterkeys():
    for t in tokenised[d]:
        if t in aggregated:
            aggregated[t] += 1
        else:
            aggregated[t] = 1
def tfidf(doc, tok):
    "Compute TFIDF score of a token in a document"
    return doc.count(tok) * math.log(float(len(byid)) / aggregated[tok])
# Annotate tweets with keywords
res = []
for name, tweet in byid.iteritems():
    doc = tokenised[name]
    keywords = sorted(set(doc), key=lambda tok: tfidf(doc, tok), reverse=True)[:5]
    tweet["keywords"] = keywords
    res.append(tweet)
simplejson.dump(res, sys.stdout)
I thought this was producing a nice summary of every tweet but nobody was particularly interested, so we moved on to adding categories to tweet. Thanks to Yuwei who put together some useful keyword sets, we managed to annotate each tweet with a place name (i.e. "Stockport"), a social place name (i.e. "pub", "bank") and a social category (i.e. "man", "woman", "landlord"...) The code is simple; the biggest work in it was the dictionary of keywords:
#!/usr/bin/python
# categorise - Annotate JSON elements with categories
#
# Copyright (C) 2010  Enrico Zini <enrico@enricozini.org>
# Copyright (C) 2010  Yuwei Lin <yuwei@ylin.org>
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
import sys, math
import simplejson
import re
# Electoral wards from http://en.wikipedia.org/wiki/List_of_electoral_wards_in_Greater_Manchester
placenames = ["Altrincham", "Sale West",
"Altrincham", "Ashton upon Mersey", "Bowdon", "Broadheath", "Hale Barns", "Hale Central", "St Mary", "Timperley", "Village",
"Ashton-under-Lyne",
"Ashton Hurst", "Ashton St Michael", "Ashton Waterloo", "Droylsden East", "Droylsden West", "Failsworth East", "Failsworth West", "St Peter",
"Blackley", "Broughton",
"Broughton", "Charlestown", "Cheetham", "Crumpsall", "Harpurhey", "Higher Blackley", "Kersal",
"Bolton North East",
"Astley Bridge", "Bradshaw", "Breightmet", "Bromley Cross", "Crompton", "Halliwell", "Tonge with the Haulgh",
"Bolton South East",
"Farnworth", "Great Lever", "Harper Green", "Hulton", "Kearsley", "Little Lever", "Darcy Lever", "Rumworth",
"Bolton West",
"Atherton", "Heaton", "Lostock", "Horwich", "Blackrod", "Horwich North East", "Smithills", "Westhoughton North", "Chew Moor", "Westhoughton South",
"Bury North",
"Church", "East", "Elton", "Moorside", "North Manor", "Ramsbottom", "Redvales", "Tottington",
"Bury South",
"Besses", "Holyrood", "Pilkington Park", "Radcliffe East", "Radcliffe North", "Radcliffe West", "St Mary", "Sedgley", "Unsworth",
"Cheadle",
"Bramhall North", "Bramhall South", "Cheadle", "Gatley", "Cheadle Hulme North", "Cheadle Hulme South", "Heald Green", "Stepping Hill",
"Denton", "Reddish",
"Audenshaw", "Denton North East", "Denton South", "Denton West", "Dukinfield", "Reddish North", "Reddish South",
"Hazel Grove",
"Bredbury", "Woodley", "Bredbury Green", "Romiley", "Hazel Grove", "Marple North", "Marple South", "Offerton",
"Heywood", "Middleton",
"Bamford", "Castleton", "East Middleton", "Hopwood Hall", "Norden", "North Heywood", "North Middleton", "South Middleton", "West Heywood", "West Middleton",
"Leigh",
"Astley Mosley Common", "Atherleigh", "Golborne", "Lowton West", "Leigh East", "Leigh South", "Leigh West", "Lowton East", "Tyldesley",
"Makerfield",
"Abram", "Ashton", "Bryn", "Hindley", "Hindley Green", "Orrell", "Winstanley", "Worsley Mesnes",
"Manchester Central",
"Ancoats", "Clayton", "Ardwick", "Bradford", "City Centre", "Hulme", "Miles Platting", "Newton Heath", "Moss Side", "Moston",
"Manchester", "Gorton",
"Fallowfield", "Gorton North", "Gorton South", "Levenshulme", "Longsight", "Rusholme", "Whalley Range",
"Manchester", "Withington",
"Burnage", "Chorlton", "Chorlton Park", "Didsbury East", "Didsbury West", "Old Moat", "Withington",
"Oldham East", "Saddleworth",
"Alexandra", "Crompton", "Saddleworth North", "Saddleworth South", "Saddleworth West", "Lees", "St James", "St Mary", "Shaw", "Waterhead",
"Oldham West", "Royton",
"Chadderton Central", "Chadderton North", "Chadderton South", "Coldhurst", "Hollinwood", "Medlock Vale", "Royton North", "Royton South", "Werneth",
"Rochdale",
"Balderstone", "Kirkholt", "Central Rochdale", "Healey", "Kingsway", "Littleborough Lakeside", "Milkstone", "Deeplish", "Milnrow", "Newhey", "Smallbridge", "Firgrove", "Spotland", "Falinge", "Wardle", "West Littleborough",
"Salford", "Eccles",
"Claremont", "Eccles", "Irwell Riverside", "Langworthy", "Ordsall", "Pendlebury", "Swinton North", "Swinton South", "Weaste", "Seedley",
"Stalybridge", "Hyde",
"Dukinfield Stalybridge", "Hyde Godley", "Hyde Newton", "Hyde Werneth", "Longdendale", "Mossley", "Stalybridge North", "Stalybridge South",
"Stockport",
"Brinnington", "Central", "Davenport", "Cale Green", "Edgeley", "Cheadle Heath", "Heatons North", "Heatons South", "Manor",
"Stretford", "Urmston",
"Bucklow-St Martins", "Clifford", "Davyhulme East", "Davyhulme West", "Flixton", "Gorse Hill", "Longford", "Stretford", "Urmston",
"Wigan",
"Aspull New Springs Whelley", "Douglas", "Ince", "Pemberton", "Shevington with Lower Ground", "Standish with Langtree", "Wigan Central", "Wigan West",
"Worsley", "Eccles South",
"Barton", "Boothstown", "Ellenbrook", "Cadishead", "Irlam", "Little Hulton", "Walkden North", "Walkden South", "Winton", "Worsley",
"Wythenshawe", "Sale East",
"Baguley", "Brooklands", "Northenden", "Priory", "Sale Moor", "Sharston", "Woodhouse Park"]
# Manual coding from Yuwei
placenames.extend(["City centre", "Tameside", "Oldham", "Bury", "Bolton",
"Trafford", "Pendleton", "New Moston", "Denton", "Eccles", "Leigh", "Benchill",
"Prestwich", "Sale", "Kearsley", ])
placenames.extend(["Trafford", "Bolton", "Stockport", "Levenshulme", "Gorton",
"Tameside", "Blackley", "City centre", "Airport", "South Manchester",
"Rochdale", "Chorlton", "Uppermill", "Castleton", "Stalybridge", "Ashton",
"Chadderton", "Bury", "Ancoats", "Whalley Range", "West Yorkshire",
"Fallowfield", "New Moston", "Denton", "Stretford", "Eccles", "Pendleton",
"Leigh", "Altrincham", "Sale", "Prestwich", "Kearsley", "Hulme", "Withington",
"Moss Side", "Milnrow", "outskirt of Manchester City Centre", "Newton Heath",
"Wythenshawe", "Mancunian Way", "M60", "A6", "Droylesden", "M56", "Timperley",
"Higher Ince", "Clayton", "Higher Blackley", "Lowton", "Droylsden",
"Partington", "Cheetham Hill", "Benchill", "Longsight", "Didsbury",
"Westhoughton"])
# Social categories from Yuwei
soccat = ["man", "woman", "men", "women", "youth", "teenager", "elderly",
"patient", "taxi driver", "neighbour", "male", "tenant", "landlord", "child",
"children", "immigrant", "female", "workmen", "boy", "girl", "foster parents",
"next of kin"]
for i in range(100):
    soccat.append("%d-year-old" % i)
    soccat.append("%d-years-old" % i)
# Types of social locations from Yuwei
socloc = ["car park", "park", "pub", "club", "shop", "premises", "bus stop",
"property", "credit card", "supermarket", "garden", "phone box", "theatre",
"toilet", "building site", "Crown court", "hard shoulder", "telephone kiosk",
"hotel", "restaurant", "cafe", "petrol station", "bank", "school",
"university"]
extras =   "placename": placenames, "soccat": soccat, "socloc": socloc  
# Normalise keyword lists
for k, v in extras.iteritems():
    # Remove duplicates
    v = list(set(v))
    # Sort by length
    v.sort(key=lambda x:len(x), reverse=True)
# Add keywords
def add_categories(tweet):
    text = tweet["text"].lower()
    for field, categories in extras.iteritems():
        for cat in categories:
            if cat.lower() in text:
                tweet[field] = cat
                break
    return tweet
# Read all the twits
records = (add_categories(x) for x in simplejson.load(sys.stdin))
simplejson.dump(list(records), sys.stdout)
All these scripts form a nice processing chain: each script takes a list of JSON records, adds some bit and passes it on. In order to see what we have so far, here is a simple script to convert the JSON twits to CSV so they can be viewed in a spreadsheet:
#!/usr/bin/python
# Convert the JSON twits to CSV
# (C) 2010 Enrico Zini <enrico@enricozini.org>
# License: WTFPL version 2 (http://sam.zoy.org/wtfpl/)
import simplejson
import sys
import csv
rows = ["id", "created_at", "text", "keywords", "placename"]
writer = csv.writer(sys.stdout)
for rec in simplejson.load(sys.stdin):
    rec["keywords"] = " ".join(rec["keywords"])
    rec["placename"] = rec.get("placename", "")
    writer.writerow([rec[row] for row in rows])
At this point we were coming up with lots of questions: "were there more reports on women or men?", "which place had most incidents?", "what were the incidents involving animals?"... Time to bring Xapian into play. This script reads all the JSON tweets and builds a Xapian index with them:
#!/usr/bin/python
# toxapian - Index JSON tweets in Xapian
#
# Copyright (C) 2010  Enrico Zini <enrico@enricozini.org>
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
import simplejson
import sys
import os, os.path
import xapian
DBNAME = sys.argv[1]
db = xapian.WritableDatabase(DBNAME, xapian.DB_CREATE_OR_OPEN)
stemmer = xapian.Stem("english")
indexer = xapian.TermGenerator()
indexer.set_stemmer(stemmer)
indexer.set_database(db)
data = simplejson.load(sys.stdin)
for rec in data:
    doc = xapian.Document()
    doc.set_data(str(rec["id"]))
    indexer.set_document(doc)
    indexer.index_text_without_positions(rec["text"])
    # Index categories as categories
    if "placename" in rec:
        doc.add_boolean_term("XP" + rec["placename"].lower())
    if "soccat" in rec:
        doc.add_boolean_term("XS" + rec["soccat"].lower())
    if "socloc" in rec:
        doc.add_boolean_term("XL" + rec["socloc"].lower())
    db.add_document(doc)
db.flush()
# Also save the whole dataset so we know where to find it later if we want to
# show the details of an entry
simplejson.dump(data, open(os.path.join(DBNAME, "all.json"), "w"))
And this is a simple command line tool to query to the database:
#!/usr/bin/python
# xgrep - Command line tool to query the GMP24 tweet Xapian database
#
# Copyright (C) 2010  Enrico Zini <enrico@enricozini.org>
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
import simplejson
import sys
import os, os.path
import xapian
DBNAME = sys.argv[1]
db = xapian.Database(DBNAME)
stem = xapian.Stem("english")
qp = xapian.QueryParser()
qp.set_default_op(xapian.Query.OP_AND)
qp.set_database(db)
qp.set_stemmer(stem)
qp.set_stemming_strategy(xapian.QueryParser.STEM_SOME)
qp.add_boolean_prefix("place", "XP")
qp.add_boolean_prefix("soc", "XS")
qp.add_boolean_prefix("loc", "XL")
query = qp.parse_query(sys.argv[2],
    xapian.QueryParser.FLAG_BOOLEAN  
    xapian.QueryParser.FLAG_LOVEHATE  
    xapian.QueryParser.FLAG_BOOLEAN_ANY_CASE  
    xapian.QueryParser.FLAG_WILDCARD  
    xapian.QueryParser.FLAG_PURE_NOT  
    xapian.QueryParser.FLAG_SPELLING_CORRECTION  
    xapian.QueryParser.FLAG_AUTO_SYNONYMS)
enquire = xapian.Enquire(db)
enquire.set_query(query)
count = 40
matches = enquire.get_mset(0, count)
estimated = matches.get_matches_estimated()
print "%d/%d results" % (matches.size(), estimated)
data = dict((str(x["id"]), x) for x in simplejson.load(open(os.path.join(DBNAME, "all.json"))))
for m in matches:
    rec = data[m.document.get_data()]
    print rec["text"]
print "%d/%d results" % (matches.size(), matches.get_matches_estimated())
total = db.get_doccount()
estimated = matches.get_matches_estimated()
print "%d results over %d documents, %d%%" % (estimated, total, estimated * 100 / total)
Neat! Now that we have a proper index that supports all sort of cool things, like stemming, tag clouds, full text search with complex queries, lookup of similar documents, suggest keywords and so on, it was just fair to put together a web service to share it with other people at the event. It helped that I had already written similar code for apt-xapian-index and dde before. Here is the server, quickly built on bottle. The very last line starts the server and it is where you can configure the listening interface and port.
#!/usr/bin/python
# xserve - Make the GMP24 tweet Xapian database available on the web
#
# Copyright (C) 2010  Enrico Zini <enrico@enricozini.org>
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
import bottle
from bottle import route, post
from cStringIO import StringIO
import cPickle as pickle
import simplejson
import sys
import os, os.path
import xapian
import urllib
import math
bottle.debug(True)
DBNAME = sys.argv[1]
QUERYLOG = os.path.join(DBNAME, "queries.txt")
data = dict((str(x["id"]), x) for x in simplejson.load(open(os.path.join(DBNAME, "all.json"))))
prefixes =   "place": "XP", "soc": "XS", "loc": "XL"  
prefix_desc =   "place": "Place name", "soc": "Social category", "loc": "Social location"  
db = xapian.Database(DBNAME)
stem = xapian.Stem("english")
qp = xapian.QueryParser()
qp.set_default_op(xapian.Query.OP_AND)
qp.set_database(db)
qp.set_stemmer(stem)
qp.set_stemming_strategy(xapian.QueryParser.STEM_SOME)
for k, v in prefixes.iteritems():
    qp.add_boolean_prefix(k, v)
def make_query(qstring):
    return qp.parse_query(qstring,
        xapian.QueryParser.FLAG_BOOLEAN  
        xapian.QueryParser.FLAG_LOVEHATE  
        xapian.QueryParser.FLAG_BOOLEAN_ANY_CASE  
        xapian.QueryParser.FLAG_WILDCARD  
        xapian.QueryParser.FLAG_PURE_NOT  
        xapian.QueryParser.FLAG_SPELLING_CORRECTION  
        xapian.QueryParser.FLAG_AUTO_SYNONYMS)
@route("/")
def index():
    query = urllib.unquote_plus(bottle.request.GET.get("q", ""))
    out = StringIO()
    print >>out, '''
<html>
<head>
<title>Query</title>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.4.2/jquery.min.js"></script>
<script type="text/javascript">
$(function() 
    $("#queryfield")[0].focus()
 )
</script>
</head>
<body>
<h1>Search</h1>
<form method="POST" action="/query">
Keywords: <input type="text" name="query" value="%s" id="queryfield">
<input type="submit">
<a href="http://xapian.org/docs/queryparser.html">Help</a>
</form>''' % query
    print >>out, '''
<p>Example: "car place:wigan"</p>

<p>Available prefixes:</p>

<ul>
'''
    for pfx in prefixes.keys():
        print >>out, "<li><a href='/catinfo/%s'>%s - %s</a></li>" % (pfx, pfx, prefix_desc[pfx])
    print >>out, '''
</ul>
'''
    oldqueries = []
    if os.path.exists(QUERYLOG):
        total = db.get_doccount()
        fd = open(QUERYLOG, "r")
        while True:
            try:
                q = pickle.load(fd)
            except EOFError:
                break
            oldqueries.append(q)
        fd.close()
        def print_query(q):
            count = q["count"]
            print >>out, "<li><a href='/query?query=%s'>%s (%d/%d %.2f%%)</a></li>" % (urllib.quote_plus(q["q"]), q["q"], count, total, count * 100.0 / total)
        print >>out, "<p>Last 10 queries:</p><ul>"
        for q in oldqueries[:-10:-1]:
            print_query(q)
        print >>out, "</ul>"
        # Remove duplicates
        oldqueries = dict(((x["q"], x) for x in oldqueries)).values()
        print >>out, "<table>"
        print >>out, "<tr><th>10 queries with most results</th><th>10 queries with least results</th></tr>"
        print >>out, "<tr><td>"
        print >>out, "<ul>"
        oldqueries.sort(key=lambda x:x["count"], reverse=True)
        for q in oldqueries[:10]:
            print_query(q)
        print >>out, "</ul>"
        print >>out, "</td><td>"
        print >>out, "<ul>"
        nonempty = [x for x in oldqueries if x["count"] > 0]
        nonempty.sort(key=lambda x:x["count"])
        for q in nonempty[:10]:
            print_query(q)
        print >>out, "</ul>"
        print >>out, "</td></tr>"
        print >>out, "</table>"
    print >>out, '''
</body>
</html>'''
    return out.getvalue()
@route("/query")
@route("/query/")
@post("/query")
@post("/query/")
def query():
    query = bottle.request.POST.get("query", bottle.request.GET.get("query", ""))
    enquire = xapian.Enquire(db)
    enquire.set_query(make_query(query))
    count = 40
    matches = enquire.get_mset(0, count)
    estimated = matches.get_matches_estimated()
    total = db.get_doccount()
    out = StringIO()
    print >>out, '''
<html>
<head><title>Results</title></head>
<body>
<h1>Results for "<b>%s</b>"</h1>
''' % query
    if estimated == 0:
        print >>out, "No results found."
    else:
        # Give as results the first 30 documents; also use them as the key
        # ones to use to compute relevant terms
        rset = xapian.RSet()
        for m in enquire.get_mset(0, 30):
            rset.add_document(m.document.get_docid())
        # Compute the tag cloud
        class NonTagFilter(xapian.ExpandDecider):
            def __call__(self, term):
                return not term[0].isupper() and not term[0].isdigit()
        cloud = []
        maxscore = None
        for res in enquire.get_eset(40, rset, NonTagFilter()):
            # Normalise the score in the interval [0, 1]
            weight = math.log(res.weight)
            if maxscore == None: maxscore = weight
            tag = res.term
            cloud.append([tag, float(weight) / maxscore])
        max_weight = cloud[0][1]
        min_weight = cloud[-1][1]
        cloud.sort(key=lambda x:x[0])
        def mklink(query, term):
            return "/query?query=%s" % urllib.quote_plus(query + " and " + term)
        print >>out, "<h2>Tag cloud</h2>"
        print >>out, "<blockquote>"
        for term, weight in cloud:
            size = 100 + 100.0 * (weight - min_weight) / (max_weight - min_weight)
            print >>out, "<a href='%s' style='font-size:%d%%; color:brown;'>%s</a>" % (mklink(query, term), size, term)
        print >>out, "</blockquote>"
        print >>out, "<h2>Results</h2>"
        print >>out, "<p><a href='/'>Search again</a></p>"
        print >>out, "<p>%d results over %d documents, %.2f%%</p>" % (estimated, total, estimated * 100.0 / total)
        print >>out, "<p>%d/%d results</p>" % (matches.size(), estimated)
        print >>out, "<ul>"
        for m in matches:
            rec = data[m.document.get_data()]
            print >>out, "<li><a href='/item/%s'>%s</a></li>" % (rec["id"], rec["text"])
        print >>out, "</ul>"
        fd = open(QUERYLOG, "a")
        qinfo = dict(q=query, count=estimated)
        pickle.dump(qinfo, fd)
        fd.close()
    print >>out, '''
<a href="/">Search again</a>

</body>
</html>'''
    return out.getvalue()
@route("/item/:id")
@route("/item/:id/")
def show(id):
    rec = data[id]
    out = StringIO()
    print >>out, '''
<html>
<head><title>Result %s</title></head>
<body>
<h1>Raw JSON record for twit %s</h1>
<pre>''' % (rec["id"], rec["id"])
    print >>out, simplejson.dumps(rec, indent=" ")
    print >>out, '''
</pre>
</body>
</html>'''
    return out.getvalue()
@route("/catinfo/:name")
@route("/catinfo/:name/")
def catinfo(name):
    prefix = prefixes[name]
    out = StringIO()
    print >>out, '''
<html>
<head><title>Values for %s</title></head>
<body>
''' % name
    terms = [(x.term[len(prefix):], db.get_termfreq(x.term)) for x in db.allterms(prefix)]
    terms.sort(key=lambda x:x[1], reverse=True)
    freq_min = terms[0][1]
    freq_max = terms[-1][1]
    def mklink(name, term):
        return "/query?query=%s" % urllib.quote_plus(name + ":" + term)
    # Build tag cloud
    print >>out, "<h1>Tag cloud</h1>"
    print >>out, "<blockquote>"
    for term, freq in sorted(terms[:20], key=lambda x:x[0]):
        size = 100 + 100.0 * (freq - freq_min) / (freq_max - freq_min)
        print >>out, "<a href='%s' style='font-size:%d%%; color:brown;'>%s</a>" % (mklink(name, term), size, term)
    print >>out, "</blockquote>"
    print >>out, "<h1>All terms</h1>"
    print >>out, "<table>"
    print >>out, "<tr><th>Occurrences</th><th>Name</th></tr>"
    for term, freq in terms:
        print >>out, "<tr><td>%d</td><td><a href='/query?query=%s'>%s</a></td></tr>" % (freq, urllib.quote_plus(name + ":" + term), term)
    print >>out, "</table>"
    print >>out, '''
</body>
</html>'''
    return out.getvalue()
# Change here for bind host and port
bottle.run(host="0.0.0.0", port=8024)
...and then we presented our work and ended up winning the contest. This was the story of how we wrote this set of award winning code.

Lior Kaplan: Recognizing apt-get output in a youtube movie

It seems that during a daily upgrade for packages in Debian unstable gave me the ability to recognize the apt-get output with just glimpsing on screen. That was exactly what happened to me when I watched Bits in pieces on you tube. In one of the scenes there s a text running up on the screen, and new rows are added at the bottom. After about two seconds after the scene I had to jump back and pause to verify if I spotted the output correctly. And it seems I was right. You re welcome to watch the movie, and notice the output at 3:06. I wonder what else does Debian puts in my subconscious
Filed under: Debian GNU/Linux

Wouter Verhelst: Samba

Warning: rant ahead Someone decided that doing a Windows-specific protocol would be a good idea. Whoever this person is, I hope he rots in hell. But that's not what this post is about. Someone else decided that doing a free software implementation of that Windows-specific protocol would be a good idea. Hence samba was born. And all was good. For the next few years, Samba kept implementing more and more features of that particular Windows-specific protocol, which kept getting changed and renamed over the years. Originally, samba could just export files, and you could specify whether users could or could not write to your files. Perhaps it already had passwords at that point not sure. Later, usernames were added, and the ability to join a Windows domain, and then another type of Windows domain, and eventually a number of other differently deficient difficulties. As these things were implemented, the ways of configuring samba to properly do all these things was made more and more complex, to the point where it now no longer seems possible to install samba without major repercussions on the 'plain' Linux installation. A bit like having an apache requiring you to add apache-specific usernames through an apache-specific NSS module (winbind anyone?) just so you could export ACLs. Oh, and forget about retaining your existing usernames. Now I'm not sure whether this is related to a) me having tried winbind at some point in the past, deciding that I didn't like the effects it had, and removing it again (with as a result that it left some traces on the system), b) the system being joined to an ADS domain which might have some special requirements, or c) this particular system having a bit of a weird history that might have fucked up some of the internal state files of samba; but at any rate, it sucks. It seems to me that somehow, over the years, samba has lost the ability to just function as a minor something that just happens to be one service on a machine much like apache on my laptop and now requires one to do a complete overhaul of the entire system. That's just stupid; I am not going to migrate users to their winbind counterparts, thankyouverymuch. Stupid ******** Of course, though unlikely, it's not impossible that I've missed something. But at any rate, even if that is the case, the hoops one needs to jump through to get to the above situations are far too numerous and complex.

Pietro Abate: network management in an heterogeneous environment

I love titles with plenty of buzz-words :) After a bit of google-ing I finally found the right combination of tools that fit my needs. Luckily they are all packaged for debian and well documented. Auto-configure your network is an old topic. There are plenty of articles and howtos. Moreover the gnome NetworkManager already solves many problems alone. But since I don't use NetworkManager I tried to find a solution that works well with wicd. The "right" combination for me so far is to use guessnet and ifplugd to handle my wired connection and use Wicd for the wireless network. In theory, you can go for a fully automated solution using guessnet and wpa_supplicant, but I find much better to hide all the complexity of wpa_supplicant and just use a simple - and unobtrusive - UI to handle my wireless. First thing is to convince Wicd to leave alone my wired connection. This is pretty easy since Wicd wont touch your wired interface if it finds an entry in /etc/network/interfaces for it. Moreover to selecting always switch to a wired connection when available will make Wicd to leave alone you routing tables even if there is a wireless connection available that is marked as automatically connect to this network. Second you need to install guessnet and ifplugd
aptititude install guessnet ifplugd
I've noticed that the default settings for ifplugd work pretty well except for the -q option that sometimes lives my interface configured even if I've been disconnected for quite a while. Using ifplugd default, I re-obtain an address every time the cable is plugged-in, maybe causing a small delay in some occasion, but I prefer waiting that de-configuring the interface by hand. Guessnet needs a tiny bit of work. The debian package has already nice defaults that you can copy directly in your /etc/network/interfaces.
# Use guessnet
mapping eth0
script guessnet-ifupdown
map default: dhcp
map timeout: 3
map verbose: true

iface interface inet manual
test missing-cable
pre-up echo No link present.
pre-up false

# By default, perform DHCP
iface dhcp inet dhcp
These will make sure you avoid long timeouts and you leave the interface configured even if no cable is connected. Now you have to add one entry per network that you want to configure:
iface home inet dhcp
test1-peer address 192.168.0.30 mac 88:43:e1:xx:xx:xx
For example to use dhcp on your home network (and of course run any if-up / if-down script as you like). Or :
iface work inet static
address 192.168.0.1
netmask 255.255.255.224
gateway 192.168.0.234
dns-search buuu.org
dns-nameservers 192.168.0.30
test peer address 192.168.0.1 mac 00:1e:xx:xx:xx
to set a static address at work. Guessnet is nice and well integrated with ifupdown. Very flexible and documented. I had however the impression that from time to time the documentation I found on the net was not in sync with the latest release... I've also noticed that a component of guessnet is not in the package anymore. Guessnet-scan is a small program that will output a stanza to be used with ifupdown based on values sniffed on the wire. This is a kinda of extreme / hackish way to get connected but i reckon a nice tool to have. Hopefully it will make it back in the package sometimes soon... ps: first post on debian planet !

Erich Schubert: Google Chrome rendering issues

If you are (like I do) experiencing issues with Google Chrome, in particular when it comes to applications such as Google Maps, try using the --disable-accelerated-compositing option.For me, the issues started with version 6.0 and resulted in various pages hanging at random, in particular graphics-heavy sites such as maps. For one of my own sites, markers started disappearing on maps at certain zoom levels. Only when it also occurred on the main Google Maps I stopped looking for bugs in my own site and started focusing on the browser ...

Erich Schubert: Google Chrome rendering issues

If you are (like I do) experiencing issues with Google Chrome, in particular when it comes to applications such as Google Maps, try using the --disable-accelerated-compositing option.For me, the issues started with version 6.0 and resulted in various pages hanging at random, in particular graphics-heavy sites such as maps. For one of my own sites, markers started disappearing on maps at certain zoom levels. Only when it also occurred on the main Google Maps I stopped looking for bugs in my own site and started focusing on the browser ...

Alexander Reichle-Schmehl: Release Critical Bug report for Week 41

The bug webinterface of the Universal Debian Database currently knows about the following release critical bugs:
In Total:732
Affecting Squeeze:327
Squeeze only:84
Remaining to be fixed in Squeeze:243
Of these 243 bugs, the following tags are set:
Pending in Squeeze:22
Patched in Squeeze:51
Duplicates in Squeeze:25
Can be fixed in a security Update:26
Contrib or non-free in Squeeze:12
Otherwise fixed in Squeeze:26
Ignoring all the above (multiple tags possible), 130 bugs need to be fixed by Debian Contributors to get Debian 6.0 Squeeze released. However, with the view of the Release Managers, 183 need to be dealt with for the release to happen. Please see Interpreting the release critical bug statistics for an explanation of the different numbers.

Gerfried Fuchs: Open Source Projectmanagement

I wrote the following as a foreword for the great German book Open Source Projektmanagement that Michael Prokop wrote. Unfortunately the foreword didn't manage it in time into the book because of various circumstances. As I'm not a person to throw away already written material, here is it for your reading pleasure. Maybe it makes you consider obtaining a copy of the German language book for yourself!
The Whole is more than the Sum of the Parts When I first met Mika at a Linux conference some years ago I quickly noticed that he had potential. The way he asked questions and tackled issues did impress me. We did meet again at various events, joined forces in various projects and knew that the result would be good. Back in the year 2004 the only real live CD was Knoppix. It always was too sluggish for me because I never really liked KDE and also OpenOffice.org was too bloated for me. I was working since a year at an Internet provider, felt comfortable in the shell and was missing the tools on Knoppix which I used daily. Often enough the frustration with the status quo starts the best projects. And so I had the idea spinning around to start a sysadmin live CD. There was just one problem here: Exactly at the same time Mika had already started such a project. And I knew one thing: it would had been a lost race to compete with him in creating the better live CD. So I joined his team and helped with the best of my knowledge. The name choice alone showed that he was the right person for the job: Grml an expression of the frustration that even he felt which spoke directly to the heart of so many. But it wasn't just the chosen name that showed that Mika was the right person for the job of the project leader. It's always the sum of the parts, no matter how minor they might look. He quickly managed a first release and in light of that also created an event which was fitting for the release of the first version: the OS04 an Open Source event which managed to get Jon Maddog Hall as keynote speaker. Mika managed through his welcoming way to lure more people into helping out. The team grew over the years, further regular releases increased the fan base, not only through the creative release names which are surely one of the parts that helped create the success. He always was open to suggestions for new tools that helped to extend the project. The lived openness did lead among other things to the case that other live CDs started to use the grml build system. JUXlala 2.0 (the system for preschool kids) is just one example. Why do I write primarily about Grml, one could get subliminal advertising probably cheaper? I do it because Grml is an extremely good example of the experience revealed in this book. And even though every project is different, it is still exactly the sum of the parts that leads to the success of a project. And exactly these parts are covered in this book and can be considered for the project at hand and get implemented accordingly. Good luck whether in large or small.
Rhonda

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Dirk Eddelbuettel: Rcpp 0.8.7

With the scheduled R release of version 2.12.0 this morning, we have just uploaded version 0.8.7 of Rcpp to CRAN; Debian will follow shortly once the autobuilders have processed R 2.12.0 This Rcpp release depends on R 2.12.0 as two things have changed. First, we play along with change in R concerning the ordering of inheritance for time classes. But secondly, and more importantly, we support in Rcpp the corresponding change R itself which brings the new ReferenceClasses. Here is corresponding bit from R's NEWS file for R 2.12.0:
    o A facility for defining reference-based S4 classes (in the OOP
      style of Java, C++, etc.) has been added experimentally to
      package methods; see ?ReferenceClasses.
[...]
    o An experimental new programming model has been added to package
      methods for reference (OOP-style) classes and methods.  See
      ?ReferenceClasses.
This was made possible in large part by code committed by John Chambers (whom we had welcomed recently as a co-author to Rcpp) building on the changes he made to R 2.12.0 itself, as well on the work Romain had done with 'Rcpp Modules'. The R help page for ReferenceClasses carries a reference (bad pun) to Rcpp 0.8.7 so these two releases do go together. This should be a lot of fun over the next little while: S3, S4, and now ReferenceClasses. We also made a number of internal changes some of which leads to speed-ups and internal improvement. The NEWS entry follows below:
0.8.7   2010-10-15
    o   As of this version, Rcpp depends on R 2.12 or greater as it interfaces 
        the new reference classes (see below) and also reflects the POSIXt class
        reordering both of which appeared with R version 2.12.0
    o   new Rcpp::Reference class, that allows internal manipulation of R 2.12.0
        reference classes. The class exposes a constructor that takes the name
        of the target reference class and a field(string) method that implements
        the proxy pattern to get/set reference fields using callbacks to the 
        R operators "$" and "$<-" in order to preserve the R-level encapsulation
    o   the R side of the preceding item allows methods to be written
        in R as per ?ReferenceClasses, accessing fields by name and
        assigning them using "<<-".  Classes extracted from modules
        are R reference classes.  They can be subclassed in R, and/or R methods
        can be defined using the $methods(...) mechanism.
    o   internal performance improvements for Rcpp sugar as well as an added
        'noNA()' wrapper to omit tests for NA values -- see the included
        examples in inst/examples/convolveBenchmarks for the speedups
    o   more internal performance gains with Functions and Environments
As always, even fuller details are in Rcpp Changelog page and the Rcpp page which also leads to the downloads, the browseable doxygen docs and zip files of doxygen output for the standard formats. A local directory has source and documentation too. Questions, comments etc should go to the rcpp-devel mailing list off the R-Forge page

Tim Retout: WIP

Summary of yesterday: I'm getting to the point where RC bugs actually keep me up at night. Very bad...

14 October 2010

Russ Allbery: pkg-config and Autoconf

Five different people asked or commented, in reply to my previous journal post about pkg-config files, why I didn't just have Autoconf generate the pkg-config configuration file directly. One could use the same template that I proposed in the previous post, but rather than adding the sed fragment to Makefile.am, instead add libfoo.pc to AC_CONFIG_FILES and let configure and config.status generate it directly. This is simpler, but it has two problems: I therefore prefer this approach, even though it's a bit more complex. I think it's more robust against both unusual ways in which people want to build my source packages and any future changes to Autoconf. Note, for example, that it's possible and sometimes useful to configure a package with a command like:
    ./configure --libdir='$ datadir '
(admittedly, more common to do that the other way arond) but that would fail with a pkg-config configuration file generated directly from Autoconf unless I'd anticipated that usage and added both datadir and datarootdir to the pkg-config template even though I wasn't using either. I've updated my build system coding style page to include this rationale.

Daniel Baumann: Adding support for Lzip compression to reprepro

Today, I prepared a patch to reprepro to add support for debian packages using Lzip compression. A patched reprepro of squeeze for amd64 and i386 can be fetched from here. An example package using Lzip compression, lzip itself, is here (for this example, the package is build as 3.0 native on purpose). Hopefully the patch will be merged so lzip compressed binary and source packages can be handled with reprepro.

Axel Beckert: Thoughts on Gitorious and GitHub plus a useful git hook

When I took over the developement of xen-tools, I looked around for an appropriate git hosting. I especially had a look at GitHub and Gitorious. If you just regard the features, GitHub is definitely more targetted on single developers and Gitorious more towards projects: At GitHub, every repository has its URL under the URL of a user page which makes it nearly impossible to have user independent, official repositories for projects which have more than one official developer. At Gitorious, every hosted repository needs to belong to a project, even if it s only a published configuration. But a project can have more than one git repository. You only seem to be able to have personal repositories if you clone some existing Gitorious repository. So from a feature point of view, the xen-tools git repositories fit way better to Gitorious hosting while the git repositories with zshrc, conkerorrc and desktop configuration files defintely have a more fitting addresses on GitHub, in my case http://github.com/xtaran/$repository. On Gitorious, they are now together under a project called Axel s configuration files at http://gitorious.org/abe which contains git repositories of my on grml s .zshrc based .zshrc, my configuration for Conkeror and all the files necessary for my ratpoison/xmobar based netbook/laptop desktop. I though feel a little bad for giving the project the very short slug name abe instead of abe-config (as I did initially) since abe is IMHO not a proper project name for my configuration files and possibly other projects would have a more reasonable claim for that project name on Gitorious. But that way it suites more its purpose: Gather some of my git repositories which don t belong to a proper project. But there s another important point when comparing Gitorious and GitHub: Free Software needs free tools as Benjamin Mako Hill posted recently on Planet Debian. Despite my (probably well known) distrust against Google and therefore also Google Code, and despite knowing the history of SourceForge becoming non-free, I was not that much aware that GitHub s software is only partially open source and therefore also not free software while Gitorious is both as it s licensed under the GNU Affero General Public License (like StatusNet/identi.ca for example) which is basically GPLv3, but its ideas applied to hosted web applications scenario (where the GPL itself doesn t grasp), too. Initially I just had the xen-tools git repositories on Gitorious and all my small one-repository projects as copies of the repositories on my own git server on GitHub to get some more publicity for them and allow social cloning . After reading Mako s article, I decided to at least have repository clones on Gitorious of all repositories I mirror at GitHub, too. That way I force nobody to use the non-free tools on GitHub for social cloning one of my git repositories. And of course I have copies of my code somewhere on the net as backup. Or to say it with Linus Torvalds (slightly updated) words: Only wimps use tape backup: real men just upload their important stuff on git, and let the rest of the world clone it. ;-) But isn t that tedious to always push your code to three repositories? No, it isn t. I just push my code to git.noone.org where I have configured the according remotes and the following post-receive hook:
#!/bin/sh
                                                                     
read oldrev newrev refname
git push gitorious $ refname:t 
git push github $ refname:t 
The only other thing necessary is to use ssh-agent and SSH agent forwarding to at least the host you re pushing to.

Rapha&#235;l Hertzog: Correctly renaming a conffile in Debian package maintainer scripts

After having dealt with the removal of obsolete conffiles, I ll now explain what you should do when a configuration file managed by dpkg must be renamed. The problem Let s suppose that version 1.2 of the software stopped providing /etc/foo.conf. Instead it provides /etc/bar.conf because the configuration file got renamed. If you do nothing special, the new conffile will be installed with the default configuration, and the old one will stay around. Any customization made by the administrator are lost in the process (in fact they are not lost, they are still in foo.conf but they are unused). Of course, you could do mv /etc/foo.conf /etc/bar.conf in the pre-installation script. But that s not satisfactory: it will generate a spurious conffile prompt that the end-user will not understand. The solution In the preinst script, you have to verify if the old conffile has been modified by the administrator. If yes, you want to keep the file around. Otherwise you know you will be able to ditch it once the upgrade is over, and you rename it to /etc/foo.conf.dpkg-remove to remember this fact. In the postinst script, you remove /etc/foo.conf.dpkg-remove. If the old conffile (/etc/foo.conf) still exists, it s because it was modified by the administrator. You make a backup of the new conffile in /etc/bar.conf.dpkg-dist and rename the old one into /etc/bar.conf. In the postrm, when called to abort an upgrade, you move /etc/foo.conf.dpkg-remove back to its original name. In practice, use dpkg-maintscript-helper dpkg-maintscript-helper can automate all those tasks. You just have to put the following snippet in the maintainer scripts (postinst, postrm, preinst):
if dpkg-maintscript-helper supports mv_conffile 2>/dev/null; then
    dpkg-maintscript-helper mv_conffile /etc/foo.conf /etc/bar.conf 1.1-3 -- "$@"
fi
In this example, I assumed that version 1.1-3 was the last version of the package that contained /etc/foo.conf (i.e. the last version released before 1.2-1 was packaged). 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. Found it useful? Be sure to not miss other packaging tips (or lessons), click here to subscribe to my free newsletter and get new articles by email (just check Send me blog updates ).
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