Revert 182991

tools/telemetry/telemetry/core/chrome/tracing_backend.py

Index: tools/telemetry/telemetry/core/chrome/tracing_backend.py
===================================================================
--- tools/telemetry/telemetry/core/chrome/tracing_backend.py	(revision 182999)
+++ tools/telemetry/telemetry/core/chrome/tracing_backend.py	(working copy)
@@ -1,133 +0,0 @@
-# Copyright (c) 2012 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 cStringIO
-import json
-import logging
-import socket
-import threading
-
-
-from telemetry.core import util
-from telemetry.core.chrome import trace_event_importer
-from telemetry.core.chrome import trace_result
-from telemetry.core.chrome import websocket
-
-
-class TracingUnsupportedException(Exception):
-  pass
-
-class TraceResultImpl(object):
-  def __init__(self, tracing_data):
-    self._tracing_data = tracing_data
-
-  def Serialize(self, f):
-    f.write('{"traceEvents": [')
-    d = self._tracing_data
-    # Note: we're not using ','.join here because the strings that are in the
-    # tracing data are typically many megabytes in size. In the fast case, f is
-    # just a file, so by skipping the in memory step we keep our memory
-    # footprint low and avoid additional processing.
-    if len(d) == 0:
-      pass
-    elif len(d) == 1:
-      f.write(d[0])
-    else:
-      f.write(d[0])
-      for i in range(1, len(d)):
-        f.write(',')
-        f.write(d[i])
-    f.write(']}')
-
-  def AsTimelineModel(self):
-    f = cStringIO.StringIO()
-    self.Serialize(f)
-    return trace_event_importer.Import(
-      f.getvalue())
-
-class TracingBackend(object):
-  def __init__(self, devtools_port):
-    debugger_url = 'ws://localhost:%i/devtools/browser' % devtools_port
-    self._socket = websocket.create_connection(debugger_url)
-    self._next_request_id = 0
-    self._cur_socket_timeout = 0
-    self._thread = None
-    self._tracing_data = []
-
-  def BeginTracing(self):
-    self._CheckNotificationSupported()
-    req = {'method': 'Tracing.start'}
-    self._SyncRequest(req)
-    # Tracing.start will send asynchronous notifications containing trace
-    # data, until Tracing.end is called.
-    self._thread = threading.Thread(target=self._TracingReader)
-    self._thread.start()
-
-  def EndTracing(self):
-    req = {'method': 'Tracing.end'}
-    self._SyncRequest(req)
-    self._thread.join()
-    self._thread = None
-
-  def GetTraceResultAndReset(self):
-    assert not self._thread
-    ret = trace_result.TraceResult(
-      TraceResultImpl(self._tracing_data))
-    self._tracing_data = []
-    return ret
-
-  def Close(self):
-    if self._socket:
-      self._socket.close()
-      self._socket = None
-
-  def _TracingReader(self):
-    while self._socket:
-      try:
-        data = self._socket.recv()
-        if not data:
-          break
-        res = json.loads(data)
-        logging.debug('got [%s]', data)
-        if 'Tracing.dataCollected' == res.get('method'):
-          value = res.get('params', {}).get('value')
-          self._tracing_data.append(value)
-        elif 'Tracing.tracingComplete' == res.get('method'):
-          break
-      except (socket.error, websocket.WebSocketException):
-        logging.warning('Timeout waiting for tracing response, unusual.')
-
-  def _SyncRequest(self, req, timeout=10):
-    self._SetTimeout(timeout)
-    req['id'] = self._next_request_id
-    self._next_request_id += 1
-    data = json.dumps(req)
-    logging.debug('will send [%s]', data)
-    self._socket.send(data)
-
-  def _SetTimeout(self, timeout):
-    if self._cur_socket_timeout != timeout:
-      self._socket.settimeout(timeout)
-      self._cur_socket_timeout = timeout
-
-  def _CheckNotificationSupported(self):
-    """Ensures we're running against a compatible version of chrome."""
-    req = {'method': 'Tracing.hasCompleted'}
-    self._SyncRequest(req)
-    while True:
-      try:
-        data = self._socket.recv()
-      except (socket.error, websocket.WebSocketException):
-        raise util.TimeoutException(
-            'Timed out waiting for reply. This is unusual.')
-      logging.debug('got [%s]', data)
-      res = json.loads(data)
-      if res['id'] != req['id']:
-        logging.debug('Dropped reply: %s', json.dumps(res))
-        continue
-      if res.get('response'):
-        raise TracingUnsupportedException(
-            'Tracing not supported for this browser')
-      elif 'error' in res:
-        return