1# Copyright (c) 2012 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"""Utilities for PyAuto."""
6
7import httplib
8import logging
9import os
10import shutil
11import socket
12import sys
13import tempfile
14import unittest
15import urlparse
16import zipfile
17
18
19class ExistingPathReplacer(object):
20  """Facilitates backing up a given path (file or dir)..
21
22  Often you want to manipulate a directory or file for testing but don't want to
23  meddle with the existing contents.  This class lets you make a backup, and
24  reinstate the backup when done.  A backup is made in an adjacent directory,
25  so you need to make sure you have write permissions to the parent directory.
26
27  Works seemlessly in cases where the requested path already exists, or not.
28
29  Automatically reinstates the backed up path (if any) when object is deleted.
30  """
31  _path = ''
32  _backup_dir = None  # dir to which existing content is backed up
33  _backup_basename = ''
34
35  def __init__(self, path, path_type='dir'):
36    """Initialize the object, making backups if necessary.
37
38    Args:
39      path: the requested path to file or directory
40      path_type: path type. Options: 'file', 'dir'. Default: 'dir'
41    """
42    assert path_type in ('file', 'dir'), 'Invalid path_type: %s' % path_type
43    self._path_type = path_type
44    self._path = path
45    if os.path.exists(self._path):
46      if 'dir' == self._path_type:
47        assert os.path.isdir(self._path), '%s is not a directory' % self._path
48      else:
49        assert os.path.isfile(self._path), '%s is not a file' % self._path
50      # take a backup
51      self._backup_basename = os.path.basename(self._path)
52      self._backup_dir = tempfile.mkdtemp(dir=os.path.dirname(self._path),
53                                          prefix='bkp-' + self._backup_basename)
54      logging.info('Backing up %s in %s' % (self._path, self._backup_dir))
55      shutil.move(self._path,
56                  os.path.join(self._backup_dir, self._backup_basename))
57    self._CreateRequestedPath()
58
59  def __del__(self):
60    """Cleanup. Reinstate backup."""
61    self._CleanupRequestedPath()
62    if self._backup_dir:  # Reinstate, if backed up.
63      from_path = os.path.join(self._backup_dir, self._backup_basename)
64      logging.info('Reinstating backup from %s to %s' % (from_path, self._path))
65      shutil.move(from_path, self._path)
66    self._RemoveBackupDir()
67
68  def _CreateRequestedPath(self):
69    # Create intermediate dirs if needed.
70    if not os.path.exists(os.path.dirname(self._path)):
71      os.makedirs(os.path.dirname(self._path))
72    if 'dir' == self._path_type:
73      os.mkdir(self._path)
74    else:
75      open(self._path, 'w').close()
76
77  def _CleanupRequestedPath(self):
78    if os.path.exists(self._path):
79      if os.path.isdir(self._path):
80        shutil.rmtree(self._path, ignore_errors=True)
81      else:
82        os.remove(self._path)
83
84  def _RemoveBackupDir(self):
85    if self._backup_dir and os.path.isdir(self._backup_dir):
86      shutil.rmtree(self._backup_dir, ignore_errors=True)
87
88
89def RemovePath(path):
90  """Remove the given path (file or dir)."""
91  if os.path.isdir(path):
92    shutil.rmtree(path, ignore_errors=True)
93    return
94  try:
95    os.remove(path)
96  except OSError:
97    pass
98
99
100def UnzipFilenameToDir(filename, dir):
101  """Unzip |filename| to directory |dir|.
102
103  This works with as low as python2.4 (used on win).
104  """
105  zf = zipfile.ZipFile(filename)
106  pushd = os.getcwd()
107  if not os.path.isdir(dir):
108    os.mkdir(dir)
109  os.chdir(dir)
110  # Extract files.
111  for info in zf.infolist():
112    name = info.filename
113    if name.endswith('/'):  # dir
114      if not os.path.isdir(name):
115        os.makedirs(name)
116    else:  # file
117      dir = os.path.dirname(name)
118      if not os.path.isdir(dir):
119        os.makedirs(dir)
120      out = open(name, 'wb')
121      out.write(zf.read(name))
122      out.close()
123    # Set permissions. Permission info in external_attr is shifted 16 bits.
124    os.chmod(name, info.external_attr >> 16L)
125  os.chdir(pushd)
126
127
128def GetCurrentPlatform():
129  """Get a string representation for the current platform.
130
131  Returns:
132    'mac', 'win' or 'linux'
133  """
134  if sys.platform == 'darwin':
135    return 'mac'
136  if sys.platform == 'win32':
137    return 'win'
138  if sys.platform.startswith('linux'):
139    return 'linux'
140  raise RuntimeError('Unknown platform')
141
142
143def PrintPerfResult(graph_name, series_name, data_point, units,
144                    show_on_waterfall=False):
145  """Prints a line to stdout that is specially formatted for the perf bots.
146
147  Args:
148    graph_name: String name for the graph on which to plot the data.
149    series_name: String name for the series (line on the graph) associated with
150                 the data.  This is also the string displayed on the waterfall
151                 if |show_on_waterfall| is True.
152    data_point: Numeric data value to plot on the graph for the current build.
153                This can be a single value or an array of values.  If an array,
154                the graph will plot the average of the values, along with error
155                bars.
156    units: The string unit of measurement for the given |data_point|.
157    show_on_waterfall: Whether or not to display this result directly on the
158                       buildbot waterfall itself (in the buildbot step running
159                       this test on the waterfall page, not the stdio page).
160  """
161  waterfall_indicator = ['', '*'][show_on_waterfall]
162  print '%sRESULT %s: %s= %s %s' % (
163      waterfall_indicator, graph_name, series_name,
164      str(data_point).replace(' ', ''), units)
165  sys.stdout.flush()
166
167
168def Shard(ilist, shard_index, num_shards):
169  """Shard a given list and return the group at index |shard_index|.
170
171  Args:
172    ilist: input list
173    shard_index: 0-based sharding index
174    num_shards: shard count
175  """
176  chunk_size = len(ilist) / num_shards
177  chunk_start = shard_index * chunk_size
178  if shard_index == num_shards - 1:  # Exhaust the remainder in the last shard.
179    chunk_end = len(ilist)
180  else:
181    chunk_end = chunk_start + chunk_size
182  return ilist[chunk_start:chunk_end]
183
184
185def WaitForDomElement(pyauto, driver, xpath):
186  """Wait for the UI element to appear.
187
188  Args:
189    pyauto: an instance of pyauto.PyUITest.
190    driver: an instance of chrome driver or a web element.
191    xpath: the xpath of the element to wait for.
192
193  Returns:
194    The element if it is found.
195    NoSuchElementException if it is not found.
196  """
197  pyauto.WaitUntil(lambda: len(driver.find_elements_by_xpath(xpath)) > 0)
198  return driver.find_element_by_xpath(xpath)
199
200
201def DoesUrlExist(url):
202  """Determines whether a resource exists at the given URL.
203
204  Args:
205    url: URL to be verified.
206
207  Returns:
208    True if url exists, otherwise False.
209  """
210  parsed = urlparse.urlparse(url)
211  try:
212    conn = httplib.HTTPConnection(parsed.netloc)
213    conn.request('HEAD', parsed.path)
214    response = conn.getresponse()
215  except (socket.gaierror, socket.error):
216    return False
217  finally:
218    conn.close()
219  # Follow both permanent (301) and temporary (302) redirects.
220  if response.status == 302 or response.status == 301:
221    return DoesUrlExist(response.getheader('location'))
222  return response.status == 200
223
224
225class _GTestTextTestResult(unittest._TextTestResult):
226  """A test result class that can print formatted text results to a stream.
227
228  Results printed in conformance with gtest output format, like:
229  [ RUN        ] autofill.AutofillTest.testAutofillInvalid: "test desc."
230  [         OK ] autofill.AutofillTest.testAutofillInvalid
231  [ RUN        ] autofill.AutofillTest.testFillProfile: "test desc."
232  [         OK ] autofill.AutofillTest.testFillProfile
233  [ RUN        ] autofill.AutofillTest.testFillProfileCrazyCharacters: "Test."
234  [         OK ] autofill.AutofillTest.testFillProfileCrazyCharacters
235  """
236
237  def __init__(self, stream, descriptions, verbosity):
238    unittest._TextTestResult.__init__(self, stream, descriptions, verbosity)
239
240  def _GetTestURI(self, test):
241    if sys.version_info[:2] <= (2, 4):
242      return '%s.%s' % (unittest._strclass(test.__class__),
243                        test._TestCase__testMethodName)
244    return '%s.%s' % (unittest._strclass(test.__class__), test._testMethodName)
245
246  def getDescription(self, test):
247    return '%s: "%s"' % (self._GetTestURI(test), test.shortDescription())
248
249  def startTest(self, test):
250    unittest.TestResult.startTest(self, test)
251    self.stream.writeln('[ RUN        ] %s' % self.getDescription(test))
252
253  def addSuccess(self, test):
254    unittest.TestResult.addSuccess(self, test)
255    self.stream.writeln('[         OK ] %s' % self._GetTestURI(test))
256
257  def addError(self, test, err):
258    unittest.TestResult.addError(self, test, err)
259    self.stream.writeln('[      ERROR ] %s' % self._GetTestURI(test))
260
261  def addFailure(self, test, err):
262    unittest.TestResult.addFailure(self, test, err)
263    self.stream.writeln('[     FAILED ] %s' % self._GetTestURI(test))
264
265
266class GTestTextTestRunner(unittest.TextTestRunner):
267  """Test Runner for displaying test results in textual format.
268
269  Results are displayed in conformance with gtest output.
270  """
271
272  def __init__(self, verbosity=1):
273    unittest.TextTestRunner.__init__(self, stream=sys.stderr,
274                                     verbosity=verbosity)
275
276  def _makeResult(self):
277    return _GTestTextTestResult(self.stream, self.descriptions, self.verbosity)
278