python -c "$(curl -fsSL https://gist.githubusercontent.com/choffmeister/1543dbdc5d152e7e95fb981952ed56e8/raw/generate-changelog.py)"

generate-changelog.py

#!/usr/bin/python

import subprocess
import os
import re
import sys
import itertools

semver_regex = '^(?:v)?(\d+)\.(\d+)\.(\d+)(\-(.*))?$'

def toint(strOrNone):
  if strOrNone:
    return int(strOrNone)
  else:
    return None

def run(cmd, cwd = None, stdout = subprocess.PIPE):
  p = subprocess.Popen(cmd, cwd = cwd, env = os.environ, stdout = stdout, stderr = subprocess.PIPE)
  stdout, err = p.communicate()
  if p.wait() != 0: raise Exception(err)
  return stdout

def git_tags():
  return run(['git', 'tag']).splitlines()

def git_commits(ref_old, ref_new):
  commits_raw = run(['git', 'log', '%s..%s' % (ref_old, ref_new), '--no-merges', '--pretty=%H %B|<|>|']).split('|<|>|')[:-1]
  commits = filter(lambda c: c != None, map(lambda c: parse_commit(c), commits_raw))
  return commits

def tags_filter(t):
  global semver_regex
  return re.search(semver_regex, t)

def tags_sort(a, b):
  global semver_regex
  semver_a = re.match(semver_regex, a)
  semver_b = re.match(semver_regex, b)
  va = [toint(semver_a.group(1)), toint(semver_a.group(2)), toint(semver_a.group(3))]
  vb = [toint(semver_b.group(1)), toint(semver_b.group(2)), toint(semver_b.group(3))]
  if cmp(va, vb) != 0:
    return cmp(va, vb)
  else:
    return -cmp(semver_a.group(5), semver_b.group(5))

def parse_commit(raw_body):
  parsed = re.match('^([a-z0-9]{40})\s(?:(\+|!|=|%|~)([^\s]+)?\s+)?(.*)$', raw_body.strip().splitlines()[0].strip())
  if parsed:
    return {
      'raw_body': raw_body.strip(),
      'hash': parsed.group(1),
      'type': parsed.group(2).strip() if parsed.group(2) else '',
      'scopes': map(lambda s: s.strip(), parsed.group(3).split(',')) if parsed.group(3) else [],
      'subject': parsed.group(4).strip() if parsed.group(4) else ''
    }
  else:
    return None

tags = ['HEAD'] + list(reversed(sorted(filter(tags_filter, git_tags()), cmp = tags_sort)))
print '# Changelog\n'
for ref_new, ref_old in zip(tags[:-1], tags[1:]):
  print '## %s\n' % ref_new
  commits = git_commits(ref_old, ref_new)
  for commit in commits:
    scopes_str = ' (' + ','.join(commit['scopes']) + ')' if len(commit['scopes']) > 0 else ''
    subject_str = commit['subject']
    hash_str = commit['hash'][:7]
    print '*%s %s [%s]' % (scopes_str, subject_str, hash_str)
  print