[Predator] Run predator.

appengine/findit/util_scripts/crash_queries/delta_test/run-predator.py

Index: appengine/findit/util_scripts/crash_queries/delta_test/run-predator.py
diff --git a/appengine/findit/util_scripts/crash_queries/delta_test/run-predator.py b/appengine/findit/util_scripts/crash_queries/delta_test/run-predator.py
new file mode 100644
index 0000000000000000000000000000000000000000..8b4dbe5427c83ea91bd0613bf279dac309de2e5e
--- /dev/null
+++ b/appengine/findit/util_scripts/crash_queries/delta_test/run-predator.py
@@ -0,0 +1,126 @@
+# Copyright 2016 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.
+
+import argparse
+import functools
+import httplib
+import json
+import logging
+import os
+import sys
+import threading
+import traceback
+
+_SCRIPT_DIR = os.path.join(os.path.dirname(__file__), os.path.pardir,
+                           os.path.pardir)
+sys.path.insert(1, _SCRIPT_DIR)
+
+import script_util
+script_util.SetUpSystemPaths()
+
+from common.chrome_dependency_fetcher import ChromeDependencyFetcher
+from crash.crash_pipeline import FinditForClientID
+from crash.crash_report import CrashReport
+from crash.culprit import Culprit
+from crash.detect_regression_range import DetectRegressionRange
+from crash.findit_for_chromecrash import FinditForChromeCrash
+from crash.type_enums import CrashClient
+from crash_queries.delta_test import delta_util
+from model.crash.crash_config import CrashConfig
+from git_checkout.local_git_repository import LocalGitRepository
+import remote_api
+
+_FRACAS_FEEDBACK_URL_TEMPLATE = (
+    'https://%s.appspot.com/crash/fracas-result-feedback?key=%s')
+
+
+def StoreResults(crash, client_id, app_id, id_to_culprits, lock, verbose=False):
+  """Stores findit result of crash into id_to_culprits dict."""
+  crash_url = _FRACAS_FEEDBACK_URL_TEMPLATE % (app_id, crash['id'])
+  try:
+    findit = FinditForClientID(client_id, LocalGitRepository())
+    stacktrace = findit._stacktrace_parser.Parse(
+        crash['stack_trace'],
+        ChromeDependencyFetcher(findit._repository).GetDependency(
+            crash['crashed_version'],
+            crash['platform']))
+    if stacktrace:
+      culprit = findit._predator.FindCulprit(CrashReport(
+          crashed_version=crash['crashed_version'],
+          signature=crash['signature'],
+          platform=crash['platform'],
+          stacktrace=stacktrace,
+          regression_range=crash['regression_range']))
+    else:
+      culprit = None
+    with lock:
+      id_to_culprits[crash['id']] = culprit
+      if verbose:

[stgao, 2016/11/17 05:03:05]

Instead of a verbose flag, could we use logging level instead?

[stgao, 2016/11/17 05:03:05]

Why the print have to be protected under the lock? what's the lock for?

[Sharu Jiang, 2016/11/17 09:03:15]

This is because logging will be messed up with those inside findit.
I created a bug to implement a simple version of logger to have this level
control.

[Sharu Jiang, 2016/11/17 09:03:16]

This is to make sure the prints from different threads won't be messed up.

+        print '\n\nCrash:', crash_url
+        print json.dumps(culprit.ToDicts()[0] if culprit else {'found': False},
+                         indent=4, sort_keys=True)
+  except Exception:
+    with lock:
+      id_to_culprits[crash['id']] = None
+      print '\n\nCrash:', crash_url

[stgao, 2016/11/17 05:03:05]

same here. Why under lock?

[Sharu Jiang, 2016/11/17 09:03:16]

Same as above.

+      print traceback.format_exc()
+
+
+def GetCulprits(crashes, client_id, app_id, verbose=False):
+  """Run predator analysis on crashes locally."""
+  # Enable remote access to app engine services.
+  remote_api.EnableRemoteApi(app_id)
+  origin = CrashConfig.Get
+  try:
+    # This hack is to solve flaky BadStatusLine excepion(crbug.com/666150) in
+    # remote api when key.get() gets called in threads.
+    CrashConfig.Get = script_util.GetLockedMethod(CrashConfig, origin)

[stgao, 2016/11/17 05:03:05]

We'd better refactor the read of config out to an upper level of code, so that
we could read it once and use it multiple times or in multithread.

I'm fine with this hack to commit this CL as a runnable version.
But this should be fixed.

[Sharu Jiang, 2016/11/17 09:03:15]

I think we have a bug(crbug.com/659354), after this is done, we can update the
code.

+    id_to_culprits = {}
+    lock = threading.Lock()
+    tasks = []
+    for crash in crashes:
+      crash['regression_range'] = DetectRegressionRange(
+          crash['historical_metadata'])
+      tasks.append({
+          'function': StoreResults,
+          'args': [crash, client_id, app_id, id_to_culprits, lock],
+          'kwargs': {'verbose': verbose}
+      })
+    script_util.RunTasks(tasks)
+
+    return id_to_culprits
+  finally:
+    CrashConfig.Get = origin
+
+
+def RunPredator():
+  """Runs delta testing between 2 different Findit versions."""
+  argparser = argparse.ArgumentParser(
+      description='Run Predator on a batch of crashes.')
+  argparser.add_argument('result_path', help='Path to store results')
+  argparser.add_argument('client', help=('Possible values are: fracas, cracas, '
+                                         'clusterfuzz. Right now, only fracas '
+                                         'is supported.'))
+  argparser.add_argument('app', help='App engine id to get config from.')
+  argparser.add_argument(
+      '--verbose',
+      '-v',
+      action='store_true',
+      default=False,
+      help='Print findit results.')
+  args = argparser.parse_args()
+
+  crashes = json.loads(raw_input())
+  if not crashes:
+    logging.error('Failed to get crashes info.')
+    return
+
+  culprits = GetCulprits(crashes, args.client, args.app, args.verbose)
+  delta_util.FlushResult(culprits, args.result_path)
+
+
+if __name__ == '__main__':
+  # Disable the trivial loggings inside predator.
+  logging.basicConfig(level=logging.ERROR)
+  RunPredator()