git-changelog

#!/usr/bin/env python3
#
# Generate changelog from git history, uses tags.
from __future__ import print_function
import sys
import os
import subprocess
import re

def run(*args):
    p = subprocess.Popen(args, stdout=subprocess.PIPE, encoding='utf-8')
    return p.communicate()[0]

PAT = re.compile(r'(.*)([ab]\d+)$')

def rev_sort_key(rev):
    m = PAT.match(rev)
    if m:
        return m.group(1), m.group(2)
    else:
        return rev, 'c1'

def main():
    revs = run("git", "tag")
    revs = [r for r in revs.split() if r.startswith('v')]
    #print 'revs', sorted(revs, key=rev_sort_key)
    revs.sort(key=rev_sort_key)
    revs.reverse()
    if run("git", "--no-pager", "log", "%s..HEAD" % revs[0]).strip():
        revs.insert(0, 'HEAD')
    revs.append('')
    print('Summary of changes')
    print('==================')
    for i, rev in enumerate(revs[:-1]):
        print()
        print(rev)
        print('-' * len(rev))
        print()
        sys.stdout.flush()
        prevref = revs[i+1]
        if prevref:
            revspec = "%s..%s" % (prevref, rev)
        else:
            revspec = rev
        #print 'revspec', revspec
        output = run("git", "--no-pager", "log", revspec)
        for line in output.split('\n'):
            if line.startswith('commit '):
                continue
            sys.stdout.write(line + '\n')

if __name__ == '__main__':
    main()