devtools: download shell binaries and set origin when run w/ --mojo-version.

mojo/devtools/common/devtoolslib/shell_arguments.py

 # Copyright 2015 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.
 
 """Produces configured shell abstractions.
 
 This module knows how to produce a configured shell abstraction based on
 shell_config.ShellConfig.
 """
 
 import os.path
 import urlparse
 
+from devtoolslib import download
+from devtoolslib import paths
 from devtoolslib.android_shell import AndroidShell
 from devtoolslib.linux_shell import LinuxShell
 from devtoolslib.shell_config import ShellConfigurationException
 
 # When spinning up servers for local origins, we want to use predictable ports
 # so that caching works between subsequent runs with the same command line.
 _LOCAL_ORIGIN_PORT = 31840
 _MAPPINGS_BASE_PORT = 31841
 
 
@@ skipping 162 matching lines @@
         once on the argument list (e.g. url-mappings) so we need to coalesce any
         overrides and the existing value into just one argument.
 
   Returns:
     A tuple of (shell, shell_args). |shell| is the configured shell abstraction,
     |shell_args| is updated list of shell arguments.
 
   Throws:
     ShellConfigurationException if shell abstraction could not be configured.
   """
+  platform = 'android-arm' if shell_config.android else 'linux-x64'
+
+  shell_path = shell_config.shell_path
+  if not shell_path and shell_config.mojo_version:
+    download_dir = os.path.join(paths.DEVTOOLS_ROOT, '_prebuilt')
+    shell_path = download.download_shell(shell_config.mojo_version, platform,
+                                         download_dir, shell_config.verbose)
+  if shell_config.verbose:
+    if shell_path:
+      print('Using shell binary at ' + shell_path)
+    else:
+      print('No shell path given, only running on Android with pre-installed '
+            'shell will be possible.')
+
   if shell_config.android:
     shell = AndroidShell(shell_config.adb_path, shell_config.target_device,
                          logcat_tags=shell_config.logcat_tags,
                          verbose=shell_config.verbose)
 
     device_status, error = shell.check_device()
     if not device_status:
       raise ShellConfigurationException('Device check failed: ' + error)
-    if shell_config.shell_path:
-      shell.install_apk(shell_config.shell_path)
+    if shell_path:
+      shell.install_apk(shell_path)
   else:
-    if not shell_config.shell_path:
+    if not shell_path:
       raise ShellConfigurationException('Can not run without a shell binary. '
-                                        'Please pass --shell-path.')
-    shell = LinuxShell(shell_config.shell_path)
+                                        'Please pass --mojo-version or '
+                                        '--shell-path.')
+    shell = LinuxShell(shell_path)
     if shell_config.use_osmesa:
       shell_args.append('--args-for=mojo:native_viewport_service --use-osmesa')
 
   shell_args = _apply_mappings(shell, shell_args, shell_config.map_url_list,
                                shell_config.map_origin_list,
                                shell_config.reuse_servers)
 
+  # Configure origin for mojo: urls.
   if shell_config.origin:
+    # If origin was set on the command line, this takes precedence.
     if _is_web_url(shell_config.origin):
       shell_args.append('--origin=' + shell_config.origin)
     else:
       local_origin_port = _LOCAL_ORIGIN_PORT
       shell_args.extend(configure_local_origin(shell, shell_config.origin,
                                                local_origin_port,
                                                shell_config.reuse_servers))
+  elif shell_config.mojo_version:
+    # Otherwise we infer the origin from the mojo_version.
+    web_origin = "https://storage.googleapis.com/mojo/services/%s/%s" % (
+        platform, shell_config.mojo_version)
+    if shell_config.verbose:
+      print('Inferring origin from `MOJO_VERSION` as: ' + web_origin)
+    shell_args.append('--origin=' + web_origin)
 
   if shell_config.content_handlers:
     for (mime_type,
          content_handler_url) in shell_config.content_handlers.iteritems():
       shell_args = append_to_argument(shell_args, '--content-handlers=',
                                       '%s,%s' % (mime_type,
                                                  content_handler_url))
 
   for dev_server_config in shell_config.dev_servers:
     shell_args = _configure_dev_server(shell, shell_args, dev_server_config,
                                        shell_config.reuse_servers,
                                        shell_config.verbose)
 
   return shell, shell_args