Git-based version information from Python script

I had this idea of generating version information for a Python script that uses ArgParse. The code is a little more than I was expecting but I think it works well. Here is the code:

	#! /usr/bin/env python
	import os
	import re
	import sys
	import logging
	import argparse
	import datetime
	import subprocess
	def run(cmd):
	(rc, stdout, stderr) = (None, '', '')
	if isinstance(cmd, basestring):
	cmd = cmd.split()
	try:
	p = subprocess.Popen(cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
	except Exception as e:
	log.debug('Ignoring `{e!s}` from {cmd}'.format(**locals()))
	else:
	(stdout, stderr) = p.communicate()
	rc = p.wait()
	log.debug('{cmd}: {rc}, {stdout!r}, {stderr!r}'.format(**locals()))
	if (rc == 0) and (not stdout):
	rc = None
	return (rc, stdout, stderr)
	def get_version():
	git_used = False
	ret = '?'
	dir = os.path.dirname(sys.argv[0])
	base = os.path.basename(sys.argv[0])
	cwd = os.getcwd()
	try:
	os.chdir(dir)
	except:
	pass
	else:
	(rc, stdout, stderr) = run(['git', 'log', '-1', base])
	"""
	commit {SHA1}
	Author: {FIRST_NAME} {LAST_NAME} <{EMAIL_ADDRESS}>
	Date: Wed Jan 16 09:32:03 2019 -0500
	.
	.
	.
	"""
	match = re.search(r'^commit\s+(\S+).*\nDate:\s+(([A-Z][a-z]{2} ){2}[ 0123]\d (\d{2}:){2}\d{2} \d{4})', stdout, re.DOTALL)
	log.debug('`git log 0` search groups: {groups}'.format(groups=match.groups() if match else None))
	if match:
	commit = match.group(1)[:6]
	timestamp = datetime.datetime.strptime(match.group(2), '%a %b %d %H:%M:%S %Y')
	log.debug('timestamp: {timestamp!s}'.format(**locals()))
	(rc, stdout, stderr) = run('git branch')
	match = re.search(r'\*\s(\S+)', stdout, re.DOTALL)
	log.debug('`git branch` search groups: {groups}'.format(groups=match.groups() if match else None))
	if match:
	branch = match.group(1)
	(rc, stdout, stderr) = run('git remote -v')
	"""
	origin https://github.com/pfuntner/gists.git (fetch)
	"""
	hits = list(re.finditer(r'(\S+)\s(https?://\S+)\s\(fetch\)', stdout))
	log.debug('`git remote -v` hits: {hits}'.format(hits=[hit.groups() for hit in hits]))
	if hits:
	hits = ['{name}:{url}'.format(name=hit.group(1), url=hit.group(2)) for hit in hits]
	ret = '{commit}, {branch}, {timestamp!s}, {hits}'.format(**locals())
	git_used = True
	os.chdir(cwd)
	if not git_used:
	ret = str(datetime.datetime.fromtimestamp(os.path.getmtime(sys.argv[0])))
	return ret
	logging.basicConfig(format='%(asctime)s %(levelname)s %(pathname)s:%(lineno)d %(msg)s')
	log = logging.getLogger()
	log.setLevel(logging.WARNING)
	parser = argparse.ArgumentParser(description='Example of doing a nifty --version')
	parser.add_argument('-v', '--verbose', dest='verbose', action='count', help='Print more messages')
	parser.add_argument('--version', action='version', version=get_version(), help='See wonderful version information')
	args = parser.parse_args()
	log.setLevel(logging.WARNING - (args.verbose or 0) * 10)
	# print get_version()

view raw version-example hosted with ❤ by GitHub

Usage

Here is an example of its usage if the script is part of a git repository:

$ ./version-example --version
b92798, master, 2019-01-18 10:35:02,
['origin:https://github.com/pfuntner/gists.git']
$

It contains:

• The SHA1 of last git commit that changed the script
• The current branch of the repository
• The date of the commit - I think the timezone element is present in this but I didn't want to deal with timezones so I'm ignoring it
• A list of the remote repositories

This is printed on two lines but that's something that ArgParse is doing, not me.

Here is an example of its usage if the script is not part of a git repository - we don't have much information to work from but we can at least get the timestamp of the script:

$ ~/tmp/version-example --version
2019-01-18 11:07:33.873846
$

You'll also get this output if the script is in the repository directory but hasn't been committed to it.