[Telemetry] Print out console output instead of page state on TimeoutException

telemetry/telemetry/internal/backends/chrome_inspector/inspector_console.py

Index: telemetry/telemetry/internal/backends/chrome_inspector/inspector_console.py
diff --git a/telemetry/telemetry/internal/backends/chrome_inspector/inspector_console.py b/telemetry/telemetry/internal/backends/chrome_inspector/inspector_console.py
index b4a7ba60a35c337224472ae5382754167ce8aac9..0d7b5e536da08cba46eef6851687d8d511752758 100644
--- a/telemetry/telemetry/internal/backends/chrome_inspector/inspector_console.py
+++ b/telemetry/telemetry/internal/backends/chrome_inspector/inspector_console.py
@@ -1,6 +1,9 @@
 # Copyright 2013 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 StringIO
+
+from telemetry.internal.backends.chrome_inspector import websocket
 
 
 class InspectorConsole(object):
@@ -13,40 +16,38 @@ class InspectorConsole(object):
 
   def _OnNotification(self, msg):
     if msg['method'] == 'Console.messageAdded':
+      assert self._message_output_stream
       if msg['params']['message']['url'] == 'chrome://newtab/':
         return
-      self._last_message = 'At %s:%i: %s' % (
+      self._last_message = '(%s) %s:%i: %s' % (
+        msg['params']['message']['level'],
         msg['params']['message']['url'],
         msg['params']['message']['line'],
         msg['params']['message']['text'])
-      if self._message_output_stream:
-        self._message_output_stream.write(
-          '%s\n' % self._last_message)
+      self._message_output_stream.write(
+        '%s\n' % self._last_message)
 
     elif msg['method'] == 'Console.messageRepeatCountUpdated':
       if self._message_output_stream:
         self._message_output_stream.write(
           '%s\n' % self._last_message)
 
-  @property
-  def message_output_stream(self):  # pylint: disable=method-hidden
-    return self._message_output_stream
-
-  @message_output_stream.setter
-  def message_output_stream(self, stream):  # pylint: disable=method-hidden
-    self._message_output_stream = stream
-    self._UpdateConsoleEnabledState()
-
-  def _UpdateConsoleEnabledState(self):
-    enabled = self._message_output_stream != None
-    if enabled == self._console_enabled:
-      return
-
-    if enabled:
-      method_name = 'enable'
-    else:
-      method_name = 'disable'
-    self._inspector_websocket.SyncRequest({
-        'method': 'Console.%s' % method_name
-        })
-    self._console_enabled = enabled
+  def GetCurrentConsoleOutputBuffer(self, timeout=10):
+    self._message_output_stream = StringIO.StringIO()
+    self._EnableConsoleOutputStream()
+    try:
+      self._inspector_websocket.DispatchNotifications(timeout)
+      return self._message_output_stream.getvalue()
+    except websocket.WebSocketTimeoutException:
+      return self._message_output_stream.getvalue()
+    finally:
+      self._DisableConsoleOutputStream()
+      self._message_output_stream.close()
+      self._message_output_stream = None
+
+
+  def _EnableConsoleOutputStream(self):
+    self._inspector_websocket.SyncRequest({'method': 'Console.enable'})
+
+  def _DisableConsoleOutputStream(self):
+    self._inspector_websocket.SyncRequest({'method': 'Console.disable'})