Lazy coding for the win

Its been a while since I wrote any new hook scripts so I thought I would refresh my knowledge before talking about them at phpconference.co.uk. I also love playing around with python – it’s straight forward, pretty and gives good ‘sad puppy’ feedback when you’ve missed a closing bracket.

So I came up with this beast to turn svn log output into a dictionary. You can then do what you like with it: output to a file, turn into html, stream to a feed, whatever.

from subprocess import check_output

repo_cmd = "svn log file:///svnrepro/tests/deleteFile/trunk"
output = check_output(repo_cmd, shell=True)

demarker = "--------------------------------------------------------\n"
contents = output.split(demarker)

ignore_these = ["[hotfix]", "[merge]"]

log_book = list()

for section in contents:
    lines = section.split("\n\n")
    if len(lines) < 2 : continue
    commit_info = lines[0]
    message = lines[1].strip()
    ignore = False
    for prefix in ignore_these:
        if message.startswith(prefix):
            ignore = True
            break
    if ignore == True: continue
    info = commit_info.split("|")
    section = dict()
    section["revision"] = info[0].strip().replace("r", "")
    section["user"] = info[1].strip()
    section["date"] = info[2].strip()
    length = info[3].strip().split(" ")
    section["messageLength"] = length[0]
    section["message"] = message
    log_book.append(section)

print log_book

What can I say, I like understanding things at a first principles level.

Of course then I remembered a cool flag which turns a predetermined text output into something much more meaningful.

repo_cmd = "svn log --xml file:///svnrepro/tests/deleteFile/trunk"

xml.etree.ElementTree is the built in python way of handling xml and, again, it’s a bit hand cranked and leads to many unnecessary lines of code. So why re-invent the wheel?

“Has someone already done this?” is rapidly becoming my first question, and yes, someone has!

https://github.com/martinblech/xmltodict

This is the second module library I tried, and is one that can actually deal with lists of elements – essential for svn log output. If you are used to handling things in JSON, it’s really easy:

from subprocess import check_output
import json
import xmltodict
# https://github.com/martinblech/xmltodict

repo_cmd = "svn log --xml file:///svnrepro/tests/deleteFile/trunk"

output = check_output(repo_cmd, shell=True)

print json.dumps(xmltodict.parse(output))

I have to admit, a little piece of me feels like I’m no longer writing ‘real’ code and that there’s nothing left unsolved or uncoded. The rest of me is doing a happy dance – now we are freed up to use technology to solve the real issues – save time, collaborate well and communicate effectively to make lives better!