Aborting bisect early when the bug specified in the bisect config is closed.

tools/auto_bisect/query_crbug.py

Index: tools/auto_bisect/query_crbug.py
diff --git a/tools/auto_bisect/query_crbug.py b/tools/auto_bisect/query_crbug.py
new file mode 100644
index 0000000000000000000000000000000000000000..b8f4fcbb5b1bb6ff3e8b82540802b783f73d337d
--- /dev/null
+++ b/tools/auto_bisect/query_crbug.py
@@ -0,0 +1,78 @@
+# Copyright 2014 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.
+
+"""Utility functions to query the chromium issue tracker.
+
+Note that documentation for the Issue Tracker API says it's DEPRECATED, however
+it seems to be in use in other places like the performance dashboard. Also,
+this module attempts to handle most exceptions thrown by querying the tracker
+so that when and if this api is turned off no impact is caused to the bisection
+process."""
+
+import json
+import urllib2
+
+SINGLE_ISSUE_URL = ('https://code.google.com/feeds/issues/p/chromium/issues'
+                    '/full?id=%s&alt=json')
+
+
+class IssueTrackerQueryException(Exception):
+  pass
+
+
+def QuerySingleIssue(issue_id, url_template=SINGLE_ISSUE_URL):
+  """Queries the tracker for a specific issue. Returns a dict.
+
+  This uses the deprecated Issue Tracker API to fetch a JSON representation of
+  the issue details.
+
+  Args:
+    issue_id: An int or string representing the issue id.
+    url_template: URL to query the tracker with '%s' instead of the bug id.
+
+  Returns:
+    A dictionary as parsed by the JSON library from the tracker response.
+
+  Raises:
+    urllib2.HTTPError when appropriate.
+  """
+  assert str(issue_id).isdigit()
+  response = urllib2.urlopen(url_template % issue_id).read()
+  return json.loads(response)
+
+
+def GetIssueState(issue_id):
+  """Returns either 'closed' or 'open' for the given bug ID.
+
+  Args:
+    issue_id: string or string-castable object containing a numeric bug ID.
+  Returns:
+    'open' or 'closed' depending on the state of the bug.
+  Raises:
+    IssueTrackerQueryException if the data cannot be retrieved or parsed.
+  """
+  try:
+    query_response = QuerySingleIssue(issue_id)
+    # We assume the query returns a single result hence the [0]
+    issue_detail = query_response['feed']['entry'][0]
+    state = issue_detail['issues$state']['$t']
+    return state
+  except urllib2.URLError:
+    raise IssueTrackerQueryException(
+        'Could not fetch the details form the issue tracker.')
+  except ValueError:
+    raise IssueTrackerQueryException(
+        'Could not parse the issue tracker\'s response as a json doc.')
+  except KeyError:
+    raise IssueTrackerQueryException(
+        'The data from the issue tracker is not in the expected format.')
+
+
+def CheckIssueClosed(issue_id):
+  """Checks if a given issue is closed. Returns False when in doubt."""
+  try:
+    return GetIssueState(issue_id) == 'closed'
+  except IssueTrackerQueryException:
+    # When we can't be sure we return false
+    return False