updater_utils.py

# Copyright (C) 2018 The Android Open Source Project
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#      http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
"""Helper functions for updaters."""

import os
import re
import subprocess
import sys
from pathlib import Path
from typing import List, Tuple, Type

from base_updater import Updater
# pylint: disable=import-error
import metadata_pb2  # type: ignore


def create_updater(metadata: metadata_pb2.MetaData, proj_path: Path,
                   updaters: List[Type[Updater]]) -> Updater:
    """Creates corresponding updater object for a project.

    Args:
      metadata: Parsed proto for METADATA file.
      proj_path: Absolute path for the project.

    Returns:
      An updater object.

    Raises:
      ValueError: Occurred when there's no updater for all urls.
    """
    for url in metadata.third_party.url:
        for updater_cls in updaters:
            updater = updater_cls(proj_path, url, metadata.third_party.version)
            if updater.is_supported_url():
                return updater

    raise ValueError('No supported URL.')


def replace_package(source_dir, target_dir) -> None:
    """Invokes a shell script to prepare and update a project.

    Args:
      source_dir: Path to the new downloaded and extracted package.
      target_dir: The path to the project in Android source tree.
    """

    print('Updating {} using {}.'.format(target_dir, source_dir))
    script_path = os.path.join(os.path.dirname(sys.argv[0]),
                               'update_package.sh')
    subprocess.check_call(['bash', script_path, source_dir, target_dir])


VERSION_SPLITTER_PATTERN: str = r'[\.\-_]'
VERSION_PATTERN: str = (r'^(?P<prefix>[^\d]*)' + r'(?P<version>\d+(' +
                        VERSION_SPLITTER_PATTERN + r'\d+)*)' +
                        r'(?P<suffix>.*)$')
VERSION_RE: re.Pattern = re.compile(VERSION_PATTERN)
VERSION_SPLITTER_RE: re.Pattern = re.compile(VERSION_SPLITTER_PATTERN)

ParsedVersion = Tuple[List[int], str, str]


def _parse_version(version: str) -> ParsedVersion:
    match = VERSION_RE.match(version)
    if match is None:
        raise ValueError('Invalid version.')
    try:
        prefix, version, suffix = match.group('prefix', 'version', 'suffix')
        versions = [int(v) for v in VERSION_SPLITTER_RE.split(version)]
        return (versions, str(prefix), str(suffix))
    except IndexError:
        # pylint: disable=raise-missing-from
        raise ValueError('Invalid version.')


def _match_and_get_version(old_ver: ParsedVersion,
                           version: str) -> Tuple[bool, bool, List[int]]:
    try:
        new_ver = _parse_version(version)
    except ValueError:
        return (False, False, [])

    right_format = (new_ver[1:] == old_ver[1:])
    right_length = len(new_ver[0]) == len(old_ver[0])

    return (right_format, right_length, new_ver[0])


def get_latest_version(current_version: str, version_list: List[str]) -> str:
    """Gets the latest version name from a list of versions.

    The new version must have the same prefix and suffix with old version.
    If no matched version is newer, current version name will be returned.
    """
    parsed_current_ver = _parse_version(current_version)

    latest = max(
        version_list,
        key=lambda ver: _match_and_get_version(parsed_current_ver, ver),
        default=None)
    if not latest:
        raise ValueError('No matching version.')
    return latest