libdot/bin/node_sync_with_chromium

#!/usr/bin/env python3
# Copyright 2019 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.

"""Update our pinned copy of node to match Chromium."""

import logging
import re
import sys

import libdot


# Where in Chromium's tree they maintain their hashes.
URI_BASE = ('https://chromium.googlesource.com/chromium/src/+/HEAD/'
            'third_party/node')
URI_LIN = '/'.join((URI_BASE, 'linux', 'node-linux-x64.tar.gz.sha1'))
URI_MAC = '/'.join((URI_BASE, 'mac', 'node-darwin-x64.tar.gz.sha1'))
URI_WIN = '/'.join((URI_BASE, 'win', 'node.exe.sha1'))

# File which records the node hashes.
HASH_FILE = libdot.BIN_DIR / 'node'


def update(uri, var):
    """Update |var| in our tree with the hash data from |uri|."""
    new_hash = fetch_data(uri)
    logging.info('Updating %s with hash %s', var, new_hash)

    # Read the current file.
    lines = HASH_FILE.read_text(encoding='utf-8').splitlines()

    # Try to update the variable in the file.
    matcher = re.compile(r"%s = '(.*)'" % (var,))
    for i, line in enumerate(lines):
        match = matcher.match(line)
        if match:
            old_hash = match.group(1)
            if new_hash != old_hash:
                logging.info('  Old hash was %s', old_hash)
                lines[i] = f"{var} = '{new_hash}'"
                break
            else:
                logging.info('  Hash up-to-date already')
                return
    else:
        logging.error('Unable to locate %s setting in %s', var, HASH_FILE)
        sys.exit(1)

    # Write out the new file content.
    HASH_FILE.write_text('\n'.join(lines) + '\n', encoding='utf-8')


def fetch_data(uri):
    """Read the gitiles base64 encoded data from |uri|."""
    data = libdot.fetch_data(f'{uri}?format=TEXT', b64=True)
    return data.getvalue().decode('utf-8').strip()


def get_parser():
    """Get a command line parser."""
    parser = libdot.ArgumentParser(description=__doc__)
    return parser


def main(argv):
    """The main func!"""
    parser = get_parser()
    _opts = parser.parse_args(argv)

    update(URI_LIN, 'NODE_LINUX_HASH')
    update(URI_MAC, 'NODE_MAC_HASH')
    update(URI_WIN, 'NODE_WIN_HASH')


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