1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
|
#!/usr/bin/env python
# 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.
"""Start and stop Web Page Replay.
Of the public module names, the following one is key:
ReplayServer: a class to start/stop Web Page Replay.
"""
import logging
import os
import signal
import subprocess
import sys
import time
import urllib
_CHROME_BASE_DIR = os.path.abspath(os.path.join(
os.path.dirname(__file__), os.pardir, os.pardir, os.pardir, os.pardir))
REPLAY_DIR = os.path.join(
_CHROME_BASE_DIR, 'src', 'third_party', 'webpagereplay')
LOG_PATH = os.path.join(
_CHROME_BASE_DIR, 'src', 'webpagereplay_logs', 'logs.txt')
# Chrome options to make it work with Web Page Replay.
def GetChromeFlags(replay_host, http_port, https_port):
return [
'--host-resolver-rules=MAP * %s,EXCLUDE localhost' % replay_host,
'--testing-fixed-http-port=%s' % http_port,
'--testing-fixed-https-port=%s' % https_port,
'--ignore-certificate-errors',
]
# Signal masks on Linux are inherited from parent processes. If anything
# invoking us accidentally masks SIGINT (e.g. by putting a process in the
# background from a shell script), sending a SIGINT to the child will fail
# to terminate it. Running this signal handler before execing should fix that
# problem.
def ResetInterruptHandler():
signal.signal(signal.SIGINT, signal.SIG_DFL)
class ReplayError(Exception):
"""Catch-all exception for the module."""
pass
class ReplayNotFoundError(ReplayError):
def __init__(self, label, path):
self.args = (label, path)
def __str__(self):
label, path = self.args
return 'Path does not exist for %s: %s' % (label, path)
class ReplayNotStartedError(ReplayError):
pass
class ReplayServer(object):
"""Start and Stop Web Page Replay.
Web Page Replay is a proxy that can record and "replay" web pages with
simulated network characteristics -- without having to edit the pages
by hand. With WPR, tests can use "real" web content, and catch
performance issues that may result from introducing network delays and
bandwidth throttling.
Example:
with ReplayServer(archive_path):
self.NavigateToURL(start_url)
self.WaitUntil(...)
Environment Variables (for development):
WPR_ARCHIVE_PATH: path to alternate archive file (e.g. '/tmp/foo.wpr').
WPR_RECORD: if set, puts Web Page Replay in record mode instead of replay.
WPR_REPLAY_DIR: path to alternate Web Page Replay source.
"""
def __init__(self, archive_path, replay_host, http_port, https_port,
replay_options=None, replay_dir=None,
log_path=None):
"""Initialize ReplayServer.
Args:
archive_path: a path to a specific WPR archive (required).
replay_options: an iterable of options strings to forward to replay.py.
replay_dir: directory that has replay.py and related modules.
log_path: a path to a log file.
"""
self.archive_path = os.environ.get('WPR_ARCHIVE_PATH', archive_path)
self.replay_options = list(replay_options or ())
self.replay_dir = os.environ.get('WPR_REPLAY_DIR', replay_dir or REPLAY_DIR)
self.log_path = log_path or LOG_PATH
self._http_port = http_port
self._https_port = https_port
self._replay_host = replay_host
if 'WPR_RECORD' in os.environ and '--record' not in self.replay_options:
self.replay_options.append('--record')
self.is_record_mode = '--record' in self.replay_options
self._AddDefaultReplayOptions()
self.replay_py = os.path.join(self.replay_dir, 'replay.py')
if self.is_record_mode:
self._CheckPath('archive directory', os.path.dirname(self.archive_path))
elif not os.path.exists(self.archive_path):
self._CheckPath('archive file', self.archive_path)
self._CheckPath('replay script', self.replay_py)
self.log_fh = None
self.replay_process = None
def _AddDefaultReplayOptions(self):
"""Set WPR command-line options. Can be overridden if needed."""
self.replay_options += [
'--host', str(self._replay_host),
'--port', str(self._http_port),
'--ssl_port', str(self._https_port),
'--use_closest_match',
'--no-dns_forwarding',
'--log_level', 'warning'
]
def _CheckPath(self, label, path):
if not os.path.exists(path):
raise ReplayNotFoundError(label, path)
def _OpenLogFile(self):
log_dir = os.path.dirname(self.log_path)
if not os.path.exists(log_dir):
os.makedirs(log_dir)
return open(self.log_path, 'w')
def IsStarted(self):
"""Checks to see if the server is up and running."""
for _ in range(30):
if self.replay_process.poll() is not None:
# The process has exited.
break
try:
up_url = '%s://%s:%s/web-page-replay-generate-200'
http_up_url = up_url % ('http', self._replay_host, self._http_port)
https_up_url = up_url % ('https', self._replay_host, self._https_port)
if (200 == urllib.urlopen(http_up_url, None, {}).getcode() and
200 == urllib.urlopen(https_up_url, None, {}).getcode()):
return True
except IOError:
time.sleep(1)
return False
def StartServer(self):
"""Start Web Page Replay and verify that it started.
Raises:
ReplayNotStartedError: if Replay start-up fails.
"""
cmd_line = [sys.executable, self.replay_py]
cmd_line.extend(self.replay_options)
cmd_line.append(self.archive_path)
self.log_fh = self._OpenLogFile()
logging.debug('Starting Web-Page-Replay: %s', cmd_line)
kwargs = {'stdout': self.log_fh, 'stderr': subprocess.STDOUT}
if sys.platform.startswith('linux') or sys.platform == 'darwin':
kwargs['preexec_fn'] = ResetInterruptHandler
self.replay_process = subprocess.Popen(cmd_line, **kwargs)
if not self.IsStarted():
log = open(self.log_path).read()
raise ReplayNotStartedError(
'Web Page Replay failed to start. Log output:\n%s' % log)
def StopServer(self):
"""Stop Web Page Replay."""
if self.replay_process:
logging.debug('Trying to stop Web-Page-Replay gracefully')
try:
url = 'http://localhost:%s/web-page-replay-command-exit'
urllib.urlopen(url % self._http_port, None, {})
except IOError:
# IOError is possible because the server might exit without response.
pass
start_time = time.time()
while time.time() - start_time < 10: # Timeout after 10 seconds.
if self.replay_process.poll() is not None:
break
time.sleep(1)
else:
try:
# Use a SIGINT so that it can do graceful cleanup.
self.replay_process.send_signal(signal.SIGINT)
except: # pylint: disable=W0702
# On Windows, we are left with no other option than terminate().
if 'no-dns_forwarding' not in self.replay_options:
logging.warning('DNS configuration might not be restored!')
try:
self.replay_process.terminate()
except: # pylint: disable=W0702
pass
self.replay_process.wait()
if self.log_fh:
self.log_fh.close()
def __enter__(self):
"""Add support for with-statement."""
self.StartServer()
return self
def __exit__(self, unused_exc_type, unused_exc_val, unused_exc_tb):
"""Add support for with-statement."""
self.StopServer()
|
