sdk/platform-tools/systrace/catapult/telemetry/telemetry/internal/backends/chrome_inspector/memory_backend.py

   1 # Copyright 2015 The Chromium Authors. All rights reserved.
   2 # Use of this source code is governed by a BSD-style license that can be
   3 # found in the LICENSE file.
   4
   5 import json
   6 import logging
   7 import socket
   8 import traceback
   9
  10 from telemetry.internal.backends.chrome_inspector import inspector_websocket
  11 from telemetry.internal.backends.chrome_inspector import websocket
  12
  13
  14 class MemoryTimeoutException(Exception):
  15   pass
  16
  17
  18 class MemoryUnrecoverableException(Exception):
  19   pass
  20
  21
  22 class MemoryUnexpectedResponseException(Exception):
  23   pass
  24
  25
  26 class MemoryBackend(object):
  27
  28   def __init__(self, inspector_socket):
  29     self._inspector_websocket = inspector_socket
  30
  31   def SetMemoryPressureNotificationsSuppressed(self, suppressed, timeout=30):
  32     """Enable/disable suppressing memory pressure notifications.
  33
  34     Args:
  35       suppressed: If true, memory pressure notifications will be suppressed.
  36       timeout: The timeout in seconds.
  37
  38     Raises:
  39       MemoryTimeoutException: If more than |timeout| seconds has passed
  40       since the last time any data is received.
  41       MemoryUnrecoverableException: If there is a websocket error.
  42       MemoryUnexpectedResponseException: If the response contains an error
  43       or does not contain the expected result.
  44     """
  45     self._SendMemoryRequest('setPressureNotificationsSuppressed',
  46                             {'suppressed': suppressed}, timeout)
  47
  48   def SimulateMemoryPressureNotification(self, pressure_level, timeout=30):
  49     """Simulate a memory pressure notification.
  50
  51     Args:
  52       pressure level: The memory pressure level of the notification ('moderate'
  53           or 'critical').
  54       timeout: The timeout in seconds.
  55
  56     Raises:
  57       MemoryTimeoutException: If more than |timeout| seconds has passed
  58       since the last time any data is received.
  59       MemoryUnrecoverableException: If there is a websocket error.
  60       MemoryUnexpectedResponseException: If the response contains an error
  61       or does not contain the expected result.
  62     """
  63     self._SendMemoryRequest('simulatePressureNotification',
  64                             {'level': pressure_level}, timeout)
  65
  66   def _SendMemoryRequest(self, command, params, timeout):
  67     method = 'Memory.%s' % command
  68     request = {
  69       'method': method,
  70       'params': params
  71     }
  72     try:
  73       response = self._inspector_websocket.SyncRequest(request, timeout)
  74     except websocket.WebSocketTimeoutException:
  75       raise MemoryTimeoutException(
  76           'Exception raised while sending a %s request:\n%s' %
  77               (method, traceback.format_exc()))
  78     except (socket.error, websocket.WebSocketException,
  79             inspector_websocket.WebSocketDisconnected):
  80       raise MemoryUnrecoverableException(
  81           'Exception raised while sending a %s request:\n%s' %
  82               (method, traceback.format_exc()))
  83
  84     if 'error' in response:
  85       code = response['error']['code']
  86       if code == inspector_websocket.InspectorWebsocket.METHOD_NOT_FOUND_CODE:
  87         logging.warning(
  88             '%s DevTools method not supported by the browser' % method)
  89       else:
  90         raise MemoryUnexpectedResponseException(
  91             'Inspector returned unexpected response for %s:\n%s' %
  92                 (method, json.dumps(response, indent=2)))
  93
  94   def Close(self):
  95     self._inspector_websocket = None