Checking Python style with pep8

A solid foundation in Python Style

If you've been coding with the Python language for a while, you have probably heard of PEP 8, the authoritative Python coding style guide authored by Guido van Rossum. While PEP 8 makes for a thrilling and inspiring read, something like a cross between Uncle John's Bathroom Reader and the US Constitution, it never occurred to me that there was a living application of the principles embodied in its chapters.

Today I learned that 'pep8' is a Python app! If you have pip installed, you can just 'pip install pep8'. If you don't have pip installed, install pip first with 'sudo apt-get install python-pip'. Pip is like apt-get, but for Python.

Pay attention, because this is the cool part. Now that you have pep8 you can use it to check your actual code against the actual PEP 8! It's like Guido himself was standing next to your desk, calmly eating canteloupe and critiquing your code for Pythonicity.

Here is the actual output I got from pep8 when I ran it for the first time on my Django project's settings.py:

$ pep8 cpi/settings.py
myproject/settings.py:6:80: E501 line too long (82 > 79 characters)
myproject/settings.py:110:1: E122 continuation line missing indentation or outdented
myproject/settings.py:133:1: W293 blank line contains whitespace
myproject/settings.py:138:1: W293 blank line contains whitespace
myproject/settings.py:143:13: W291 trailing whitespace
myproject/settings.py:156:80: E501 line too long (90 > 79 characters)
myproject/settings.py:130:1: E122 continuation line missing indentation or outdented
myproject/settings.py:151:14: E261 at least two spaces before inline comment
myproject/settings.py:152:22: E261 at least two spaces before inline comment
myproject/settings.py:153:16: E261 at least two spaces before inline comment
myproject/settings.py:231:1: E303 too many blank lines (3)

Ouch, that's a lot of errors! These are all the blunders in Python style which don't actually prevent execution of the code when it's run through the interpreter.

I was able to clear up all the errors, after which pep8 will run with no output:

$ pep8 cpi/settings.py

Joy!

Building TrinityCore 9847 with TrinityDB r34 on Ubuntu 10.04

Well, another TrinityCore/TDB release has arrived (http://forum.trinitycore.org/topic/28139-tdb-3351134-love-hate-and-passion-has-been-released/), so I'm rebuilding my Trinity server from scratch and sharing the process again. Happily, I saw much fewer errors than when I built r33. No errors, in fact!

Accordingly, this guide describes the process of setting up TrinityCore revision 9847 with TrinityDB 335.11.34 (TDB r34) on an Ubuntu 10.04 system. The directions should work on Ubuntu 9.10 but have not been tested there. I got most of my clues from http://www.trinitycore.info/index.php?title=Installing_TrinityCore_on_recent_Linux-based_systems. I highly suggest you keep that document handy while following this guide, as it goes into detail on many explanations which I will be glossing over.

Installing TrinityCore dependencies on Ubuntu 10.04

This guide is meant to accompany my release-specific build guides for TrinityCore/TDB releases on Ubuntu, in order to cut down on duplicate content in those posts since these procedures for brand new installations don't change.

TrinityCore dependency packages in Ubuntu

First, install the Ubuntu packages required for building TrinityCore.

Building TrinityCore with TrinityDB r33 on Ubuntu 10.04

Setting up TrinityCore on Ubuntu 10.04

The awesomeness of 5-boxing localhost

IMPORTANT: USE UPDATED R34 GUIDE AT http://sectio-aurea.blogspot.com/2010/09/trinitycore-9847-tdb-r34-ubuntu-1004.html - THANKS

Building Xnee 3.06 on Ubuntu Lucid 10.04

Recently, I wanted to use Xnee (http://www.sandklef.com/xnee/) to automate some GUI application actions on an Ubuntu Lucid 10.04 installation, but I found that the version of Xnee available from the Lucid repositories still has some problems. Specifically, this older Xnee version, 3.02-2ubuntu2, still contains workarounds for some previously existing Xorg RECORD extension problems which have themselves now been fixed in Lucid. The outcome of this mismatch is that recording fails with any of cnee, gnee or pnee. This is resolved in the next release of Ubuntu, 10.10 "Maverick", which includes Xnee 3.06, but I preferred not to upgrade the entire system to a pre-release state just to get this one application working.