Add infrastructure to download golang and build AppRTC collider.

download_appengine_and_mercurial.py

 #!/usr/bin/python
 # Copyright 2013 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.
 
 """Downloads the appengine SDK from WebRTC storage and unpacks it.
 
 Requires that depot_tools is installed and in the PATH. This script expects
 to run with Chrome's base dir as the working directory, e.g. where the .gclient
 file is. This is what should happen if this script is invoked as a hook action.
 """
 
-import hashlib
+import glob
 import os
-import shutil
 import sys
 import subprocess
-import zipfile
 
+import utils
 
-def _DownloadAppEngineZipFile(webrtc_deps_path):
+def _DownloadResources(webrtc_deps_path):
   print 'Downloading files in %s...' % webrtc_deps_path
 
   extension = 'bat' if 'win32' in sys.platform else 'py'
   cmd = ['download_from_google_storage.%s' % extension,
          '--bucket=chromium-webrtc-resources',
          '--directory', webrtc_deps_path]
   subprocess.check_call(cmd)
 
 
-def _ComputeSHA1(path):
-  if not os.path.exists(path):
-    return 0
-
-  sha1 = hashlib.sha1()
-  file_to_hash = open(path, 'rb')
-  try:
-    sha1.update(file_to_hash.read())
-  finally:
-    file_to_hash.close()
-
-  return sha1.hexdigest()
-
-
-# This is necessary since Windows won't allow us to unzip onto an existing dir.
-def _DeleteOldAppEngineDir():
-  app_engine_dir = 'google_appengine'
-  print 'Deleting %s in %s...' % (app_engine_dir, os.getcwd())
-  shutil.rmtree(app_engine_dir, ignore_errors=True)
-
-
-def _Unzip(path):
-  print 'Unzipping %s in %s...' % (path, os.getcwd())
-  zip_file = zipfile.ZipFile(path)
-  try:
-    zip_file.extractall()
-  finally:
-    zip_file.close()
+def _StripVersionNumberFromMercurialFolder():
+  unpacked_name = glob.glob('mercurial*')
+  assert len(unpacked_name) == 1, 'Should have precisely one mercurial!'
+  os.rename(unpacked_name[0], 'mercurial')
 
 
 def main(argv):
   if len(argv) == 1:
     return 'Usage: %s <path to webrtc.DEPS>' % argv[0]
 
   webrtc_deps_path = argv[1]
-  zip_path = os.path.join(webrtc_deps_path, 'google-appengine.zip')
-  old_zip_sha1 = _ComputeSHA1(zip_path)
+  appengine_zip_path = os.path.join(webrtc_deps_path, 'google-appengine.zip')
+  old_appengine_sha1 = utils.ComputeSHA1(appengine_zip_path)
 
-  _DownloadAppEngineZipFile(webrtc_deps_path)
+  mercurial_tar_path = os.path.join(webrtc_deps_path, 'mercurial-src.tar.gz')
+  old_mercurial_sha1 = utils.ComputeSHA1(mercurial_tar_path)
 
-  if old_zip_sha1 != _ComputeSHA1(zip_path):
-    _DeleteOldAppEngineDir()
-    _Unzip(zip_path)
+  _DownloadResources(webrtc_deps_path)
 
+  if old_appengine_sha1 != utils.ComputeSHA1(appengine_zip_path):
+    utils.DeleteDirNextToGclient('google_appengine')
+    utils.UnpackToWorkingDir(appengine_zip_path)
+
+  if old_mercurial_sha1 != utils.ComputeSHA1(mercurial_tar_path):
+    utils.DeleteDirNextToGclient('mercurial')
+    utils.UnpackToWorkingDir(mercurial_tar_path)
+    _StripVersionNumberFromMercurialFolder()
 
 if __name__ == '__main__':
   sys.exit(main(sys.argv))