Script to extract components from OWNERS files throughout the repo.

tools/checkteamtags/owners_file_tags.py

Index: tools/checkteamtags/owners_file_tags.py
diff --git a/tools/checkteamtags/owners_file_tags.py b/tools/checkteamtags/owners_file_tags.py
new file mode 100644
index 0000000000000000000000000000000000000000..fc8d1f57ebc5ecb8a8d315aa2f0819f75e34061f
--- /dev/null
+++ b/tools/checkteamtags/owners_file_tags.py
@@ -0,0 +1,85 @@
+# 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.
+
+import os
+import re
+
+from collections import defaultdict
+
+
+def parse(filename):
+  """Searches the file for lines that start with `# TEAM:` or `# COMPONENT:`.
+
+  Args:
+    filename (str): path to the file to parse.
+  Returns:
+    (team (str), component(str)): The team and component found in the file, the
+        last one of each if multiple, None if missing.
+  """
+  team = None
+  component = None
+  team_regex = re.compile('\s*#\s*TEAM\s*:\s*(\S+)')
+  component_regex = re.compile('\s*#\s*COMPONENT\s*:\s*(\S+)')
+  with open(filename) as f:
+    for line in f:
+      team_matches = team_regex.match(line)
+      if team_matches:
+        team = team_matches.group(1)
+      component_matches = component_regex.match(line)
+      if component_matches:
+        component = component_matches.group(1)
+  return team, component
+
+
+def aggregate_components_from_owners(root):
+  """Traverses the given dir and parse OWNERS files for team and component tags.
+
+  Args:
+    root (str): the path to the src directory.
+
+  Returns:
+    A pair (data, warnings) where data is a dict of the form
+      {'component-to-team': {'Component1': 'team1@chr...', ...},
+       'dir-to-component': {'/path/to/1': 'Component1', ...}}
+      and warnings is a list of strings.
+  """
+  warnings = []
+  component_to_team = defaultdict(set)
+  dir_to_component = {}
+  for dirname, _, files in os.walk(root):
+    # Proofing against windows casing oddities.
+    owners_file_names = [f for f in files if f.upper() == 'OWNERS']
+    if owners_file_names:
+      owners_full_path = os.path.join(dirname, owners_file_names[0])
+      owners_rel_path = os.path.relpath(owners_full_path, root)
+      team, component = parse(owners_full_path)
+      if component:
+        dir_to_component[os.path.relpath(dirname, root)] = component
+        if team:
+          component_to_team[component].add(team)
+      else:
+        warnings.append('%s has no COMPONENT tag' % owners_rel_path)
+  mappings = {'component-to-team': component_to_team,
+              'dir-to-component': dir_to_component}
+  errors = validate_one_team_per_component(mappings)
+  return unwrap(mappings), warnings, errors
+
+
+def validate_one_team_per_component(m):
+  """Validates that each component is associated with at most 1 team."""
+  errors = []
+  # TODO(robertocn): Validate the component names: crbug.com/679540
+  component_to_team = m['component-to-team']
+  for c in component_to_team:
+    if len(component_to_team[c]) > 1:
+      errors.append('Component %s has more than one team assigned to it: %s' % (
+          c, ', '.join(list(component_to_team[c]))))
+  return errors
+
+
+def unwrap(mappings):
+  """Remove the set() wrapper around values in component-to-team mapping."""
+  for c in mappings['component-to-team']:
+    mappings['component-to-team'][c] = mappings['component-to-team'][c].pop()
+  return mappings