Open Source Monorail

appengine/monorail/search/searchpipeline.py

Index: appengine/monorail/search/searchpipeline.py
diff --git a/appengine/monorail/search/searchpipeline.py b/appengine/monorail/search/searchpipeline.py
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+# 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
+
+"""Helper functions and classes used in issue search and sorting."""
+
+import logging
+import re
+
+from features import savedqueries_helpers
+from search import query2ast
+from services import tracker_fulltext
+from services import fulltext_helpers
+from tracker import tracker_helpers
+
+
+# Users can use "is:starred" in queries to limit
+# search results to issues starred by that user.
+IS_STARRED_RE = re.compile(r'\b(?![-@.:])is:starred\b(?![-@.:])', re.I)
+
+# Users can use "me" in other fields to refer to the logged in user name.
+ME_RE = re.compile(r'(?<=[=:])me\b(?![-@.:=])', re.I)
+
+
+def _AccumulateIssueProjectsAndConfigs(
+    cnxn, project_dict, config_dict, services, issues):
+  """Fetch any projects and configs that we need but haven't already loaded.
+
+  Args:
+    cnxn: connection to SQL database.
+    project_dict: dict {project_id: project} of projects that we have
+        already retrieved.
+    config_dict: dict {project_id: project} of configs that we have
+        already retrieved.
+    services: connections to backends.
+    issues: list of issues, which may be parts of different projects.
+
+  Returns:
+    Nothing, but projects_dict will be updated to include all the projects that
+    contain the given issues, and config_dicts will be updated to incude all
+    the corresponding configs.
+  """
+  new_ids = {issue.project_id for issue in issues}
+  new_ids.difference_update(project_dict.iterkeys())
+  new_projects_dict = services.project.GetProjects(cnxn, new_ids)
+  project_dict.update(new_projects_dict)
+  new_configs_dict = services.config.GetProjectConfigs(cnxn, new_ids)
+  config_dict.update(new_configs_dict)
+
+
+def ReplaceKeywordsWithUserID(me_user_id, query):
+  """Substitutes User ID in terms such as is:starred and me.
+
+  This is done on the query string before it is parsed because the query string
+  is used as a key for cached search results in memcache.  A search for by one
+  user for owner:me should not retrieve results stored for some other user.
+
+  Args:
+    me_user_id: Null when no user is logged in, or user ID of the logged in
+        user when doing an interactive search, or the viewed user ID when
+        viewing someone else's dashboard, or the subscribing user's ID when
+        evaluating subscriptions.
+    query: The query string.
+
+  Returns:
+    A string with "me" and "is:starred" removed or replaced by new terms that
+    use the numeric user ID provided.
+  """
+  if me_user_id:
+    star_term = 'starredby:%d' % me_user_id
+    query = IS_STARRED_RE.sub(star_term, query)
+    query = ME_RE.sub(str(me_user_id), query)
+  else:
+    query = IS_STARRED_RE.sub('', query)
+    query = ME_RE.sub('', query)
+
+  return query
+
+
+def ParseQuery(mr, config, services):
+  """Parse the user's query.
+
+  Args:
+    mr: commonly used info parsed from the request.
+    config: The ProjectConfig PB for the project.
+    services: connections to backends.
+
+  Returns:
+    A pair (ast, is_fulltext) with the parsed query abstract syntax tree
+    and a boolean that is True if the query included any fulltext terms.
+  """
+  canned_query = savedqueries_helpers.SavedQueryIDToCond(
+    mr.cnxn, services.features, mr.can)
+  query_ast = query2ast.ParseUserQuery(
+    mr.query, canned_query, query2ast.BUILTIN_ISSUE_FIELDS, config)
+
+  is_fulltext_query = bool(
+    query_ast.conjunctions and
+    fulltext_helpers.BuildFTSQuery(
+      query_ast.conjunctions[0], tracker_fulltext.ISSUE_FULLTEXT_FIELDS))
+
+  return query_ast, is_fulltext_query
+