Add first changes needed for OWNERS file support.
This changes adds the first pass of code needed for OWNERS files.
In total there should probably be maybe four user-visible changes:
* new gcl/git-cl "suggest-reviewers" command
* a presubmit hook on upload to automatically add the reviewers
* an addition to gcl/git-cl status command that tells you
which files still need review/approval.
* a presubmit hook on commit to ensure all of the needed reviewers
have approved the file.
This change implements a core "owners Database" object with the
dumbest possible algorithm for determining a covering set of reviewers,
and the skeleton of the presubmit hooks. This code will not be
used by anything yet, and is also missing unit tests.
Review URL: http://codereview.chromium.org/6581030
git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@76342 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/owners.py b/owners.py
new file mode 100644
index 0000000..76fb51f
--- /dev/null
+++ b/owners.py
@@ -0,0 +1,90 @@
+# Copyright (c) 2010 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.
+
+"""A database of OWNERS files."""
+
+class Assertion(AssertionError):
+ pass
+
+class Database(object):
+ def __init__(self, root, fopen, os_path):
+ """Initializes the database of owners for a repository.
+
+ Args:
+ root: the path to the root of the Repository
+ all_owners: the list of every owner in the system
+ open: function callback to open a text file for reading
+ os_path: module/object callback with fields for 'exists',
+ 'dirname', and 'join'
+ """
+ self.root = root
+ self.fopen = fopen
+ self.os_path = os_path
+
+ # Mapping of files to authorized owners.
+ self.files_owned_by = {}
+
+ # Mapping of owners to the files they own.
+ self.owners_for = {}
+
+ # In-memory cached map of files to their OWNERS files.
+ self.owners_file_for = {}
+
+ # In-memory cache of OWNERS files and their contents
+ self.owners_files = {}
+
+ def OwnersFor(self, files):
+ """Returns a sets of reviewers that will cover the set of files.
+
+ The set of files are paths relative to (and under) self.root."""
+ self._LoadDataNeededFor(files)
+ return self._CoveringSetOfOwnersFor(files)
+
+ def FilesAreCoveredBy(self, files, reviewers):
+ return not self.FilesNotCoveredBy(files, reviewers)
+
+ def FilesNotCoveredBy(self, files, reviewers):
+ covered_files = set()
+ for reviewer in reviewers:
+ covered_files = covered_files.union(self.files_owned_by[reviewer])
+ return files.difference(covered_files)
+
+ def _LoadDataNeededFor(self, files):
+ for f in files:
+ self._LoadOwnersFor(f)
+
+ def _LoadOwnersFor(self, f):
+ if f not in self.owners_for:
+ owner_file = self._FindOwnersFileFor(f)
+ self.owners_file_for[f] = owner_file
+ self._ReadOwnersFile(owner_file, f)
+
+ def _FindOwnersFileFor(self, f):
+ # This is really a "do ... until dirname = ''"
+ dirname = self.os_path.dirname(f)
+ while dirname:
+ owner_path = self.os_path.join(dirname, 'OWNERS')
+ if self.os_path.exists(owner_path):
+ return owner_path
+ dirname = self.os_path.dirname(dirname)
+ owner_path = self.os_path.join(dirname, 'OWNERS')
+ if self.os_path.exists(owner_path):
+ return owner_path
+ raise Assertion('No OWNERS file found for %s' % f)
+
+ def _ReadOwnersFile(self, owner_file, affected_file):
+ owners_for = self.owners_for.setdefault(affected_file, set())
+ for owner in self.fopen(owner_file):
+ owner = owner.strip()
+ self.files_owned_by.setdefault(owner, set()).add(affected_file)
+ owners_for.add(owner)
+
+ def _CoveringSetOfOwnersFor(self, files):
+ # TODO(dpranke): implement the greedy algorithm for covering sets, and
+ # consider returning multiple options in case there are several equally
+ # short combinations of owners.
+ every_owner = set()
+ for f in files:
+ every_owner = every_owner.union(self.owners_for[f])
+ return every_owner