When updating a rpm package it is nice to include a summary of the
changes made since the last time. anaconda does this with a nifty
script written by dcantrell called
makebumpver
which also enforces some RHEL rules and handles changing the
version. I only needed the changelog part of this so I modified the
script a bit to remove the extras:
import os
import re
import subprocess
import sys
import textwrap
from optparse import OptionParser
class ChangeLog:
    def __init__(self, tag):
        self.tag = tag
        self.ignore = None
    def _getCommitDetail(self, commit, field):
        proc = subprocess.Popen(['git', 'log', '-1',
                                 "--pretty=format:%s" % field, commit],
                                stdout=subprocess.PIPE,
                                stderr=subprocess.PIPE).communicate()
        ret = proc[0].strip('\n').split('\n')
        if len(ret) == 1 and ret[0].find('@') != -1:
            ret = ret[0].split('@')[0]
        elif len(ret) == 1:
            ret = ret[0]
        else:
            ret = filter(lambda x: x != '', ret)
        return ret
    def getLog(self):
        range = "%s.." % (self.tag)
        proc = subprocess.Popen(['git', 'log', '--pretty=oneline', range],
                                stdout=subprocess.PIPE,
                                stderr=subprocess.PIPE).communicate()
        lines = filter(lambda x: x.find('l10n: ') != 41 and \
                                 x.find('Merge commit') != 41 and \
                                 x.find('Merge branch') != 41,
                       proc[0].strip('\n').split('\n'))
        if self.ignore and self.ignore != '':
            for commit in self.ignore.split(','):
                lines = filter(lambda x: not x.startswith(commit), lines)
        log = []
        for line in lines:
            fields = line.split(' ')
            commit = fields[0]
            summary = self._getCommitDetail(commit, "%s")
            long = self._getCommitDetail(commit, "%b")
            author = self._getCommitDetail(commit, "%aE")
            log.append(("%s (%s)" % (summary.strip(), author)))
        return log
    def formatLog(self):
        s = ""
        for msg in self.getLog():
            sublines = textwrap.wrap(msg, 77)
            s = s + "- %s\n" % sublines[0]
            if len(sublines) > 1:
                for subline in sublines[1:]:
                    s = s + "  %s\n" % subline
        return s
def main():
    parser = OptionParser()
    parser.add_option("-t", "--tag", dest="tag",
                      help="Last tag, changelog is commits after this tag")
    (options, args) = parser.parse_args()
    cl = ChangeLog(options.tag)
    print cl.formatLog()
if __name__ == "__main__":
    main()
I've copied my version of this
here for
easy downloading. Run it like this -
git-changelog -t livecd-tools-15.0 and the output is: