nassh/bin/generate-changelog

#!/usr/bin/env python3
# Copyright 2020 The Chromium OS Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

"""Utility code for generating ChangeLog.html."""

import html
import logging
import os
import sys
from typing import List

import nassh
import libdot


CHANGELOG_FILE = os.path.join(nassh.DIR, 'html', 'changelog.html')
CHANGELOG_TEMPLATE = os.path.join(nassh.DIR, 'html', 'changelog.html.in')

CHANGELOG_ENTRY_TEMPLATE = """\
<div><a href="https://crrev.com/%(commit)s">%(summary)s</a></div>
"""


def generate_html(tag: str, entries: List[List[str]]):
    """Generate the changelog file from |entries|."""
    with open(CHANGELOG_TEMPLATE, 'r', encoding='utf-8') as fp:
        template = fp.read()
    output = ''
    for (commit, summary) in entries:
        output += CHANGELOG_ENTRY_TEMPLATE % {
            'commit': commit,
            'summary': html.escape(summary),
        }
    output = template.replace('%%COMMITS%%', output).replace('%%TAG%%', tag)
    with open(CHANGELOG_FILE, 'w', encoding='utf-8') as fp:
        fp.write(output)


def get_entries(tag: str) -> List[List[str]]:
    """Find all the commits since |tag|."""
    output = libdot.run(
        ['git', 'log', '--format=%H %s', f'{tag}..HEAD'],
        capture_output=True, encoding='utf-8', cwd=nassh.DIR).stdout
    return [x.split(' ', 1) for x in output.splitlines()]


def get_previous_tag() -> str:
    """Find the most recent nassh tag."""
    return libdot.run(
        ['git', 'describe', '--tags', '--abbrev=0', '--match', 'nassh-*',
         'HEAD'],
        capture_output=True, encoding='utf-8', cwd=nassh.DIR).stdout.strip()


def generate_changelog(prev_tag: str = None):
    """Generate the changelog.html file from recent git history."""
    # Ebuilds don't currently checkout the entire tree, so stub it.
    if 'EAPI' in os.environ:
        logging.warning('Generating a stub changelog for ebuild.')
        generate_html('', [])
        return

    if prev_tag is None:
        prev_tag = get_previous_tag()
    logging.info('Generating history since tag "%s"', prev_tag)
    entries = get_entries(prev_tag)
    logging.info('Found %i commits', len(entries))
    generate_html(prev_tag, entries)


def get_parser():
    """Get a command line parser."""
    parser = libdot.ArgumentParser(description=__doc__)
    parser.add_argument('--commit',
                        help='Commit to generate history back to')
    return parser


def main(argv: List[str]):
    """The main func!"""
    parser = get_parser()
    opts = parser.parse_args(argv)

    generate_changelog(prev_tag=opts.commit)



if __name__ == '__main__':
    sys.exit(main(sys.argv[1:]))