Tag Archives: Python

Psycopg migrated to Bazaar

28 April, 2008 – 10:07 pm

Last week we moved psycopg from Subversion to Bazaar.  I did the migration using Gustavo Niemeyer’s svn2bzr tool with a few tweaks to map the old Subversion committer IDs to the email address form conventionally used by Bazaar.
The tool does a good job of following tree copies and create related Bazaar branches.  It doesn’t have […]

By James Henstridge | Posted in Uncategorised | Also tagged , , | Comments (0)

Psycopg2 2.0.7 Released

15 April, 2008 – 2:55 pm

Yesterday Federico released version 2.0.7 of psycopg2 (a Python database adapter for PostgreSQL).  I made a fair number of the changes in this release to make it more usable for some of Canonical’s applications.  The new release should work with the development version of Storm, and shouldn’t be too difficult to get everything working with […]

By James Henstridge | Posted in Uncategorised | Also tagged | Comments (2)

Running Valgrind on Python Extensions

24 March, 2008 – 7:47 am

As most developers know, Valgrind is an invaluable tool for finding memory leaks. However, when debugging Python programs the pymalloc allocator gets in the way.
There is a Valgrind suppression file distributed with Python that gets rid of most of the false positives, but does not give particularly good diagnostics for memory allocated through pymalloc. […]

By James Henstridge | Posted in Uncategorised | Also tagged | Comments (2)

Two‐Phase Commit in Python’s DB‐API

4 March, 2008 – 2:19 pm

Marc uploaded a new revision of the Python DB-API 2.0 Specification yesterday that documents the new two phase commit extension that I helped develop on the db-sig mailing list.
My interest in this started from the desire to support two phase commit in Storm – without that feature there are far fewer occasions where its ability […]

By James Henstridge | Posted in Uncategorised | Also tagged , | Comments Off

Zeroconf Branch Sharing with Bazaar

19 February, 2008 – 3:36 pm

At Canonical, one of the approaches taken to accelerate development is to hold coding sprints (otherwise known as hackathons, hackfests or similar). Certain things get done a lot quicker face to face compared to mailing lists, IRC or VoIP.
When collaborating with someone at one of these sprints the usual way to let others look […]

By James Henstridge | Posted in Uncategorised | Also tagged , , , , , | Comments (5)

Re: Python factory-like type instances

12 February, 2008 – 1:54 pm

Nicolas: Your metaclass example is a good example of when not to use metaclasses. I wouldn’t be surprised if it is executed slightly different to how you expect. Let’s look at how Foo is evaluated, starting with what’s written:

class Foo:
__metaclass__ = FooMeta

This is equivalent to the following assignment:

Foo […]

By James Henstridge | Posted in Uncategorised | Comments (6)

urlparse considered harmful

10 December, 2007 – 2:57 pm

Over the weekend, I spent a number of hours tracking down a bug caused by the cache in the Python urlparse module. The problem has already been reported as Python bug 1313119, but has not been fixed yet.
First a bit of background. The urlparse module does what you’d expect and parses a URL […]

By James Henstridge | Posted in Uncategorised | Comments (7)

Storm Released

15 July, 2007 – 10:24 pm

This week at the EuroPython conference, Gustavo Niemeyer announced the release of Storm and gave a tutorial on using it.
Storm is a new object relational mapper for Python that was developed for use in some Canonical projects, and we’ve been working on moving Launchpad over to it. I’ll discuss a few of the […]

By James Henstridge | Posted in Uncategorised | Also tagged , | Comments Off

ZeroConf support for Bazaar

25 March, 2007 – 10:05 am

When at conferences and sprints, I often want to see what someone else is working on, or to let other people see what I am working on. Usually we end up pushing up to a shared server and using that as a way to exchange branches. However, this can be quite frustrating when […]

By James Henstridge | Posted in Uncategorised | Also tagged , , | Comments (6)

Python time.timezone / time.altzone edge case

31 December, 2006 – 4:22 am

While browsing the log of one of my Bazaar branches, I noticed that the commit messages were being recorded as occurring in the +0800 time zone even though WA switched over to daylight savings.
Bazaar stores commit dates as a standard UNIX seconds since epoch value and a time zone offset in seconds. So the […]

By James Henstridge | Posted in Uncategorised | Also tagged | Comments (2)

Bad Behavior has blocked 837 access attempts in the last 7 days.