[pinpoint] Add a mapping from repository URLs to repository names.

dashboard/dashboard/pinpoint/models/change/repository.py

Index: dashboard/dashboard/pinpoint/models/change/repository.py
diff --git a/dashboard/dashboard/pinpoint/models/change/repository.py b/dashboard/dashboard/pinpoint/models/change/repository.py
new file mode 100644
index 0000000000000000000000000000000000000000..52785829d509928fda34e3d67d8e863c7b8e3217
--- /dev/null
+++ b/dashboard/dashboard/pinpoint/models/change/repository.py
@@ -0,0 +1,46 @@
+# Copyright 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.
+
+from dashboard.common import namespaced_stored_object
+
+
+_REPOSITORIES_KEY = 'repositories'
+_URLS_TO_NAMES_KEY = 'repository_urls_to_names'
+
+
+def RepositoryUrl(name):

[perezju, 2017/09/19 11:34:31]

nit: Can you add docstrings to these on a follow up?

Maybe also add some of the explanation you gave on the CL description as
comments here in the code.

+  repositories = namespaced_stored_object.Get(_REPOSITORIES_KEY)
+  return repositories[name]['repository_url']
+
+
+def Repository(url, add_if_missing=False):
+  if url.endswith('.git'):
+    url = url[:-4]
+
+  urls_to_names = namespaced_stored_object.Get(_URLS_TO_NAMES_KEY)
+  try:
+    return urls_to_names[url]
+  except KeyError:
+    if add_if_missing:
+      return _AddRepository(url)
+    raise
+
+
+def _AddRepository(url):
+  name = url.split('/')[-1]
+
+  # Add to main repositories dict.
+  repositories = namespaced_stored_object.Get(_REPOSITORIES_KEY)
+  if name in repositories:
+    raise AssertionError("Attempted to add a repository that's already in the "
+                         'Datastore: %s: %s' % (name, url))
+  repositories[name] = {'repository_url': url}
+  namespaced_stored_object.Set(_REPOSITORIES_KEY, repositories)
+
+  # Add to URL -> name mapping dict.
+  urls_to_names = namespaced_stored_object.Get(_URLS_TO_NAMES_KEY)
+  urls_to_names[url] = name
+  namespaced_stored_object.Set(_URLS_TO_NAMES_KEY, urls_to_names)
+
+  return name