git.py

import os, time
import subprocess

class repo:
	def __init__(self, repodir="."):
		self.repodir=repodir

	def __callgit(self, cmd, *args):
		command = ['git', cmd]
		for a in args:
			command.append(a)
		env = {'GIT_DIR':self.repodir}
		p = subprocess.PIPE
		print 'Calling',command,'on',self.repodir
		return subprocess.Popen(command, env=env, stdin=p, stdout=p)
	callgit = __callgit # Make it temporarily available outside

	def snapshot(self, ref='HEAD', format='zip', filter=None):
		results = self.__callgit('archive', '--format=%s' % format, ref)
		if filter:
			output = subprocess.Popen(filter, stdin=results.stdout, stdout=subprocess.PIPE).stdout
		else:
			output = results.stdout
		while True:
			yield output.read(0x1000)

test.py

#!/usr/bin/python
import git
import web
from subprocess import *


class hello:
	def GET(self):
		for a in ['callgit', 'snapshot']:
			yield '<A HREF="%s">%s</a>' % (a,a)

class callgit:
	def GET(self):
		web.header('Content-Type', 'application/binary')
		web.header('Content-Disposition', 'attachment; filename=test.tar.gz')

		repoobj = git.repo('/var/spool/gitosis/repositories/sensorcentral.git')

		output = repoobj.callgit('archive', '--format=tar', '4cc3471f876f8a6814c567902a07b5f15083b9d4').stdout
		return Popen(('gzip', '-9c', '-'), stdout=PIPE, stdin=output).stdout

class snapshot:
	def GET(self):
		web.header('Content-Type', 'application/binary')
		web.header('Content-Disposition', 'attachment; filename=test.tar.gz')

		repoobj = git.repo('/var/spool/gitosis/repositories/sensorcentral.git')
		return repoobj.snapshot('4cc3471f876f8a6814c567902a07b5f15083b9d4', 'tar', ('gzip', '-9c', '-'))

if __name__ == "__main__":
	urls = ("/", "hello",
		"/callgit", "callgit",
		"/snapshot", "snapshot")
	web.application(urls, globals()).run()