Add changelog devtool

Signed-off-by: William Casarin <jb55@jb55.com>

devtools/changelog.py

@@ -0,0 +1,171 @@
+#!/usr/bin/env python3
+# Copied from ElementsProject/lightning, thanks! :)
+
+from collections import namedtuple
+from datetime import datetime
+from mako.template import Template
+import argparse
+import os
+import re
+import requests
+import shlex
+import subprocess
+import sys
+
+# What sections do we support in the changelog:
+sections = [
+    'added',
+    'changed',
+    'deprecated',
+    'fixed',
+    'removed',
+    'experimental',
+]
+
+repo = 'damus-io/damus'
+
+Entry = namedtuple("Entry", ["commit", "pullreq", "content", "section"])
+Link = namedtuple("Link", ["ref", "content", "url"])
+
+
+def git(cmd):
+    cmd = shlex.split(cmd)
+    out = subprocess.check_output(['git'] + cmd)
+    return out.decode('UTF-8')
+
+
+def get_commit_range():
+    """Find a commit range that we should collect the CHANGELOG for.
+    """
+    description = git("describe")
+    version = description.split('-')[0]
+    return "{version}..master".format(version=version)
+
+
+def get_log_entries(commitrange):
+    commit = None
+    logs = git("log {commitrange}".format(commitrange=commitrange))
+    entries = []
+
+    for l in logs.split('\n'):
+        m = re.match(r'^commit ([A-Fa-f0-9]{40})$', l)
+        if m:
+            commit = m.group(1)
+
+        m = re.match(
+            r'^\s+Changelog-({}): (.*)$'.format("|".join(sections)), l, re.IGNORECASE)
+        if not m:
+            continue
+
+        # Now try to resolve the pull request that originated this commit:
+        headers = {
+            'Accept': 'application/vnd.github.groot-preview+json',
+        }
+
+        if os.environ.get('GH_TOKEN'):
+            headers['Authorization'] = 'token ' + os.environ.get('GH_TOKEN')
+
+        url = 'https://api.github.com/repos/{repo}/commits/{commit}/pulls'.format(repo=repo, commit=commit)
+        content = requests.get(url, headers=headers).json()
+        if content.get(0) is not None:
+            pullreq = content[0]['number']
+        else:
+            pullreq = None
+
+        e = Entry(commit, pullreq, m.group(2), m.group(1).lower())
+        entries.append(e)
+
+    return entries
+
+
+def linkify(entries):
+    links = []
+    for e in entries:
+        links.append(Link(
+            ref='#{}'.format(e.pullreq),
+            content=e.content,
+            url="https://github.com/{repo}/pull/{pullreq}".format(repo=repo, pullreq=e.pullreq)
+        ))
+    return list(set(links))
+
+
+def group(entries):
+    groups = {s: [] for s in sections}
+    for e in entries:
+        groups[e.section].append(e)
+    for s in sections:
+        if len(groups[s]) == 0:
+            del groups[s]
+    return groups
+
+
+def commit_date(commitsha):
+    """Get the date of the specified commit.
+    """
+    line = git("show -s --format=%ci")
+    dt = datetime.strptime(line.strip(), '%Y-%m-%d %H:%M:%S %z')
+    return dt
+
+
+template = Template("""<%def name="group(entries)">
+% for e in entries:
+ % if e.pullreq is not None:
+     - ${e.content} ([#${e.pullreq}])
+ % else:
+     - ${e.content}
+ % endif
+% endfor
+
+</%def><%def name="group_links(entries)">
+% for e in entries:
+[${e.pullreq}]: https://github.com/{repo}/pull/${e.pullreq}
+% endfor
+</%def>
+<!--
+TODO: Insert version codename, and username of the contributor that named the release.
+-->
+
+${h2} [${version}] - ${date.strftime("%Y-%m-%d")}
+
+% for section in sections:
+${h3} ${section.capitalize()}
+${group(groups[section]) | trim}
+% endfor
+
+% for l in links:
+[${l.ref}]: ${l.url}
+% endfor
+[${version}]: https://github.com/{repo}/releases/tag/v${version}""")
+
+
+if __name__ == "__main__":
+    parser = argparse.ArgumentParser(
+        description='Generate a changelog summary for a given commit range'
+    )
+    parser.add_argument('commitrange', type=str, nargs='?',
+                        help='Range of commits to consider (format: <from_commit>..<to_commit>',
+                        default=get_commit_range())
+
+    args = parser.parse_args()
+
+    if '..' not in args.commitrange:
+        print("Commit range must include '..' to separate 'from_commit' and 'to_commit'")
+        sys.exit(1)
+
+    fromcommit, tocommit = args.commitrange.split('..')
+    entries = get_log_entries(args.commitrange)
+    groups = group(entries)
+    date = commit_date(tocommit)
+
+    print(template.render(
+        groups=groups,
+        repo=repo,
+        sections=groups.keys(),
+        h2='##',
+        h3='###',
+        version=tocommit[1:],
+        date=date,
+        links=linkify(entries),
+    ))
+
+