Open Source Monorail

appengine/monorail/search/backendsearch.py

+# Copyright 2016 The Chromium Authors. All rights reserved.
+# Use of this source code is govered by a BSD-style
+# license that can be found in the LICENSE file or at
+# https://developers.google.com/open-source/licenses/bsd
+
+"""A servlet that implements the backend of issues search.
+
+The GET request to a backend search has the same query string
+parameters as the issue list servlet.  But, instead of rendering a
+HTML page, the backend search handler returns a JSON response with a
+list of matching, sorted issue IID numbers from this shard that are
+viewable by the requesting user.
+
+Each backend search request works within a single shard.  Each
+besearch backend job can access any single shard while processing a request.
+
+The current user ID must be passed in from the frontend for permission
+checking.  The user ID for the special "me" term can also be passed in
+(so that you can view another user's dashboard and "me" will refer to
+them).
+"""
+
+import logging
+import time
+
+from framework import jsonfeed
+from search import backendsearchpipeline
+from tracker import tracker_constants
+
+
+class BackendSearch(jsonfeed.InternalTask):
+  """JSON servlet for issue search in a GAE backend."""
+
+  CHECK_SAME_APP = True
+  _DEFAULT_RESULTS_PER_PAGE = tracker_constants.DEFAULT_RESULTS_PER_PAGE
+
+  def HandleRequest(self, mr):
+    """Search for issues and respond with the IIDs of matching issues.
+
+    Args:
+      mr: common information parsed from the HTTP request.
+
+    Returns:
+      Results dictionary in JSON format.
+    """
+    # Users are never logged into backends, so the frontends tell us.
+    logging.info('query_project_names is %r', mr.query_project_names)
+    pipeline = backendsearchpipeline.BackendSearchPipeline(
+        mr, self.services, self.profiler, self._DEFAULT_RESULTS_PER_PAGE,
+        mr.query_project_names, mr.specified_logged_in_user_id,
+        mr.specified_me_user_id)
+    pipeline.SearchForIIDs()
+
+    start = time.time()
+    # Backends work in parallel to precache issues that the
+    # frontend is very likely to need.
+    _prefetched_issues = self.services.issue.GetIssues(
+        mr.cnxn, pipeline.result_iids[:mr.start + mr.num],
+        shard_id=mr.shard_id)
+    logging.info('prefetched and memcached %d issues in %d ms',
+                 len(pipeline.result_iids[:mr.start + mr.num]),
+                 int(1000 * (time.time() - start)))
+
+    return {
+        'unfiltered_iids': pipeline.result_iids,
+        'search_limit_reached': pipeline.search_limit_reached,
+        }