Dynamically generate a heading for Extension Docs API pages

chrome/common/extensions/docs/server2/availability_data_source.py

+# Copyright (c) 2012 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 file_system import FileNotFoundError
+import object_store
+
+class AvailabilityDataSource:
+  def __init__(self,
+               version_data_source,
+               version_number,
+               object_store):
+    self._version_data_source = version_data_source
+    self._version_number = version_number
+    self._object_store = object_store
+
+  def FindEarliestAvailability(self, api_name):
+    """Searches in descending order through filesystem caches tied to specific
+    chrome version numbers and looks for the existence of a specified api,
+    |api_name|. When an api is not found, returns the previous version number
+    (the last known version where the api was found).
+    """
+    version = self._object_store.Get(
+        api_name,
+        object_store.AVAILABILITY_DATA_SOURCE).Get()
+
+    if version is not None:
+      return version
+
+    version = int(self._version_number)

[cduvall, 2013/03/21 18:43:53]

dont reuse version as an int. Call it something else

[epeterson, 2013/03/25 19:35:11]

Done.

+    while version >= 18: #extension api's are not present before version 18

[cduvall, 2013/03/21 18:43:53]

Put comment above while

[epeterson, 2013/03/25 19:35:11]

Done.

+      api_data_source = self._version_data_source.GetDataSourceForVersion(
+          "%d" % version)

[cduvall, 2013/03/21 18:43:53]

single quotes

[epeterson, 2013/03/25 19:35:11]

Done.

+      try:
+        api_data_source.tryGet(api_name)
+        version -= 1

[cduvall, 2013/03/21 18:43:53]

instead of doing version -= 1 in both places, use a finally block

[epeterson, 2013/03/25 19:35:11]

I didn't want that piece of code to always execute (the version shouldn't be
decremented if the file name isn't found in either case); just putting the line
at the end of the loop was the solution.

+      except FileNotFoundError:
+        try:
+          api_data_source.tryGet(api_name, tryNonUnix=True)
+          version -= 1
+        except FileNotFoundError:
+          break
+
+    version += 1
+    #if version > self._version_number: api was not found in the current version
+    version = "%d" % version
+    self._object_store.Set(api_name,
+                           version,
+                           object_store.AVAILABILITY_DATA_SOURCE)
+    return version