Docserver: Only fetch content versions in the crons, not their contents.

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

Index: chrome/common/extensions/docs/server2/template_data_source.py
diff --git a/chrome/common/extensions/docs/server2/template_data_source.py b/chrome/common/extensions/docs/server2/template_data_source.py
index c7ba8069151f635bf3daa5ba28b6e81d52a2e780..63d26e5f635252172efaf4ab70530e5499f16b4b 100644
--- a/chrome/common/extensions/docs/server2/template_data_source.py
+++ b/chrome/common/extensions/docs/server2/template_data_source.py
@@ -12,7 +12,7 @@ from extensions_paths import (
     ARTICLES_TEMPLATES, INTROS_TEMPLATES, PRIVATE_TEMPLATES)
 from file_system import FileNotFoundError
 from future import All
-from path_util import AssertIsDirectory
+from path_util import AssertIsDirectory, Join
 
 
 class TemplateDataSource(DataSource):
@@ -35,13 +35,27 @@ class TemplateDataSource(DataSource):
       return None
 
   def Cron(self):
-    futures = []
-    for root, _, files in self._file_system.Walk(self._dir):
-      futures += [self._template_cache.GetFromFile(
-                      posixpath.join(self._dir, root, FormatKey(f)))
-                  for f in files
-                  if posixpath.splitext(f)[1] == '.html']
-    return All(futures)
+    def map_cron_paths(op):
+      results = []
+      for root, _, files in self._file_system.Walk(self._dir):
+        results += [op(Join(self._dir, root, FormatKey(f)))
+                    for f in files
+                    if posixpath.splitext(f)[1] == '.html']
+      return results
+
+    # Immediately stat everything so that files are guaranteed to be eventually
+    # up to date. See http://crbug.com/398042 for background.
+    #
+    # XXX: For all: do this asynchronously. Just forget about content. Perhaps
+    # run a second round of Crons that we allow to fail.
+    All(map_cron_paths(self._file_system.StatAsync)).Get()
+
+    # Update content in the future.
+    # XXX don't do this, see comment in APIModels.
+    # XXX: Perhaps there should be a method like CronForPaths, RunCronForPaths,
+    # CachePaths, whatever... on CompiledFileSystem. That way it can implement
+    # this behaviour and I don't have to keep commenting what's going on.
+    return All(map_cron_paths(self._template_cache.GetFromFile))
 
 
 class ArticleDataSource(TemplateDataSource):