Send screenshots back to the client for debugging

chrome/test/webdriver/chromedriver_tests.py

 #!/usr/bin/python
 
 # Copyright (c) 2011 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.
 
 """Tests for ChromeDriver.
 
 If your test is testing a specific part of the WebDriver API, consider adding
 it to the appropriate place in the WebDriver tree instead.
 """
 
+import hashlib
+import os
 import platform
-import os
 import sys
 import unittest
+import urllib
 import urllib2
 import urlparse
 
 from chromedriver_launcher import ChromeDriverLauncher
 import chromedriver_paths
 from gtest_text_test_runner import GTestTextTestRunner
 
 sys.path += [chromedriver_paths.SRC_THIRD_PARTY]
 sys.path += [chromedriver_paths.PYTHON_BINDINGS]
 
 import simplejson as json
 
 from selenium.webdriver.remote.command import Command
 from selenium.webdriver.remote.webdriver import WebDriver
 
 
+def DataDir():
+  """Returns the path to the data dir chrome/test/data."""
+  return os.path.normpath(
+    os.path.join(os.path.dirname(__file__), os.pardir, "data"))
+
+
+def GetFileURLForPath(path):
+  """Get file:// url for the given path.
+  Also quotes the url using urllib.quote().
+  """
+  abs_path = os.path.abspath(path)
+  if sys.platform == 'win32':
+    # Don't quote the ':' in drive letter ( say, C: ) on win.
+    # Also, replace '\' with '/' as expected in a file:/// url.
+    drive, rest = os.path.splitdrive(abs_path)
+    quoted_path = drive.upper() + urllib.quote((rest.replace('\\', '/')))
+    return 'file:///' + quoted_path
+  else:
+    quoted_path = urllib.quote(abs_path)
+    return 'file://' + quoted_path
+
+
 class Request(urllib2.Request):
   """Extends urllib2.Request to support all HTTP request types."""
 
   def __init__(self, url, method=None, data=None):
     """Initialise a new HTTP request.
 
     Arguments:
       url: The full URL to send the request to.
       method: The HTTP request method to use; defaults to 'GET'.
       data: The data to send with the request as a string. Defaults to
@@ skipping 107 matching lines @@
     self.assertNotEqual(cookie_dict, None)
     self.assertEqual(cookie_dict["value"], "this is a test")
 
   def testDeleteCookie(self):
     self.testAddCookie();
     self._driver.delete_cookie("chromedriver_cookie_test")
     cookie_dict = self._driver.get_cookie("chromedriver_cookie_test")
     self.assertEqual(cookie_dict, None)
 
 
+class ScreenshotTest(unittest.TestCase):
+  """Tests to verify screenshot retrieval"""
+
+  REDBOX = "automation_proxy_snapshot/set_size.html"
+
+  def setUp(self):
+    self._launcher = ChromeDriverLauncher()
+    self._driver = WebDriver(self._launcher.GetURL(), {})
+
+  def tearDown(self):
+    self._driver.quit()
+    self._launcher.Kill()
+
+  def testScreenCaptureAgainstReference(self):
+    # Create a red square of 2000x2000 pixels.
+    url = GetFileURLForPath(os.path.join(DataDir(),
+                                         self.REDBOX))
+    url += "?2000,2000"
+    self._driver.get(url)
+    s = self._driver.get_screenshot_as_base64();
+    self._driver.get_screenshot_as_file("/tmp/foo.png")
+    h = hashlib.md5(s).hexdigest()
+    # Compare the PNG created to the reference hash.
+    self.assertEquals(h, '12c0ade27e3875da3d8866f52d2fa84f')
+
+
 class SessionTest(unittest.TestCase):
   """Tests dealing with WebDriver sessions."""
 
   def setUp(self):
     self._launcher = ChromeDriverLauncher()
 
   def tearDown(self):
     self._launcher.Kill()
 
   def testCreatingSessionShouldRedirectToCorrectURL(self):
@@ skipping 152 matching lines @@
     # for this.
     result = body1.execute(Command.ELEMENT_EQUALS, {
       'other': body2.id
     })
     self.assertTrue(result['value'])
 
 
 if __name__ == '__main__':
   unittest.main(module='chromedriver_tests',
                 testRunner=GTestTextTestRunner(verbosity=1))