tools/checkteamtags/extract_components.py

#!/usr/bin/env python
# Copyright (c) 2017 The Chromium Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

"""Parses OWNERS recursively and generates a machine readable component mapping.

OWNERS files are expected to contain a well-formatted pair of tags as shown
below.  A presubmit check exists that validates this.

This script finds lines in the OWNERS files such as:
  `# TEAM: team@chromium.org` and
  `# COMPONENT: Tools>Test>Findit`
and dumps this information into a json file.

Refer to crbug.com/667952
"""

import json
import optparse
import os
import sys

from owners_file_tags import aggregate_components_from_owners


_DEFAULT_SRC_LOCATION = os.path.join(
    os.path.dirname(__file__), os.pardir, os.pardir)

_README = """
This file is generated by src/tools/checkteamtags/extract_components.py
by parsing the contents of OWNERS files throughout the chromium source code and
extracting `# TEAM:` and `# COMPONENT:` tags.

Manual edits of this file will be overwritten by an automated process.
""".splitlines()


def write_results(filename, data):
  """Write data to the named file, or the default location."""
  if not filename:
    filename = 'component_map.json'
  with open(filename, 'w') as f:
    f.write(data)


def main(argv):
  usage = """Usage: python %prog [options] [<root_dir>]
  root_dir  specifies the topmost directory to traverse looking for OWNERS
            files, defaults to two levels up from this file's directory.
            i.e. where src/ is expected to be.

Examples:
  python %prog
  python %prog /b/build/src
  python %prog -v /b/build/src
  python %prog -w /b/build/src
  python %prog -o ~/components.json /b/build/src
  """
  parser = optparse.OptionParser(usage=usage)
  parser.add_option('-w', '--write', action='store_true',
                    help='If no errors occur, write the mappings to disk.')
  parser.add_option('-v', '--verbose', action='store_true',
                    help='Print warnings.')
  parser.add_option('-f', '--force_print', action='store_true',
                    help='Print the mappings despite errors.')
  parser.add_option('-o', '--output_file', help='Specify file to write the '
                    'mappings to instead of the default: <CWD>/'
                    'component_map.json (implies -w)')
  options, args = parser.parse_args(argv[1:])
  if args:
    root = args[0]
  else:
    root = _DEFAULT_SRC_LOCATION

  mappings, warnings, errors = aggregate_components_from_owners(root)
  if options.verbose:
    for w in warnings:
      print w

  for e in errors:
    print e

  mappings['AAA-README']= _README
  mapping_file_contents = json.dumps(mappings, sort_keys=True, indent=2)
  if options.write or options.output_file:
    if errors:
      print 'Not writing to file due to errors'
      if options.force_print:
        print mapping_file_contents
    else:
      write_results(options.output_file, mapping_file_contents)
  else:
    print mapping_file_contents

  return len(errors)


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