test: Fix Chromecast testing in lab (#6643)

These changes are necessary for compatibility with Chromecast WebDriver Server v2.

 - Fix a bug in Karma's flat environment support (joeyparrish/karma@9875e98)
 - Add a test boot file to load CAF on Chromecast devices; required by Chromecast WebDriver Server v2's redirect mode (flat environment at that level)
 - Also load this cast-boot file in support.html
 - Rename/reorganize Cast-related externs, which were messy even before the addition of CAF
 - Remove proxy-cast-platform.js; no longer needed as we move to flatten the test environment
 - Ignore error events with "null" error; these appear on Linux Chromecasts, only since including CAF
 - Ignore error events that are actually strings; these appear on Linux Chromecasts, only since including CAF
 - Disable Fuchsia in the lab until autoplay issues can be resolved

build/build.py

@@ -45,6 +45,7 @@ import argparse
 import logging
 import os
 import re
+import shutil
 
 import compiler
 import generateLocalizations
@@ -302,11 +303,12 @@ class Build(object):
     if not closure.compile(closure_opts, force):
       return False
 
+    source_base = shakaBuildHelpers.get_source_base()
+
     # Don't pass local node modules to the extern generator.  But don't simply
     # exclude the string 'node_modules', either, since Shaka Player could be
     # rebuilt after installing it as a node module.
-    node_modules_path = os.path.join(
-        shakaBuildHelpers.get_source_base(), 'node_modules')
+    node_modules_path = os.path.join(source_base, 'node_modules')
     local_include = set([f for f in self.include if node_modules_path not in f])
     extern_generator = compiler.ExternGenerator(local_include, build_name)
 
@@ -323,6 +325,11 @@ class Build(object):
     if not ts_def_generator.generate(force):
       return False
 
+    # Copy this file to dist/ where support.html can use it
+    shutil.copy(
+        os.path.join(source_base, 'test', 'test', 'cast-boot.js'),
+        os.path.join(source_base, 'dist', 'cast-boot.js'))
+
     return True
 
 

build/check.py

@@ -283,7 +283,6 @@ def check_tests(args):
       [closure_base_js]))
   files.add(os.path.join(base, 'demo', 'common', 'asset.js'))
   files.add(os.path.join(base, 'demo', 'common', 'assets.js'))
-  files.add(os.path.join(base, 'proxy-cast-platform.js'))
 
   localizations = compiler.GenerateLocalizations(None)
   localizations.generate(args.force)

build/conformance.textproto

@@ -73,7 +73,6 @@ requirement {
   whitelist_regexp: "demo/"
   whitelist_regexp: "test/"
   whitelist_regexp: "node_modules/"
-  whitelist_regexp: "proxy-cast-platform.js"
 
   # This global variable is generated by Google-internal tooling, and should be
   # allowed.  It will not end up in the compiled code, only at an intermediate
@@ -287,7 +286,6 @@ requirement: {
     "shaka.util.Timer instead."
   whitelist_regexp: "demo/"
   whitelist_regexp: "test/"
-  whitelist_regexp: "proxy-cast-platform.js"
 }
 
 # Disallow eval, except when testing for modern JS syntax in demo

build/shaka-lab.yaml

@@ -241,6 +241,8 @@ ChromecastGTV:
 ChromecastHub:
   browser: chromecast
   version: hub
+  # Disabled by default until we resolve issues with autoplay on Fuchsia.
+  disabled: true
 
 ChromecastSpeaker:
   # This is a headless device, and our tests are not yet known to work here.

externs/cast-namespace.js

@@ -0,0 +1,14 @@
+/*! @license
+ * Shaka Player
+ * Copyright 2024 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+/**
+ * @fileoverview Google Cast namespace definitions, shared by other externs
+ * files.
+ * @externs
+ */
+
+/** @const */
+var cast = {};

externs/cast-sdk-v2.js

@@ -15,10 +15,6 @@
 var __onGCastApiAvailable;
 
 
-/** @const */
-var cast = {};
-
-
 /** @const */
 cast.receiver = {};
 

externs/cast-sdk-v3.js

@@ -0,0 +1,35 @@
+/*! @license
+ * Shaka Player
+ * Copyright 2024 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+/**
+ * @fileoverview Externs for the limited subset of the Cast Application
+ * Framework (Receiver SDK v3) that we use in our test infrastructure.
+ *
+ * @externs
+ */
+
+/** @const */
+cast.framework = {};
+
+/**
+ * @typedef {{
+ *   statusText: string,
+ *   disableIdleTimeout: boolean,
+ *   skipPlayersLoad: boolean
+ * }}
+ */
+cast.framework.CastReceiverOptions;
+
+cast.framework.CastReceiverContext = class {
+  /** @return {!cast.framework.CastReceiverContext} */
+  static getInstance() {}
+
+  /**
+   * @param {!cast.framework.CastReceiverOptions} options
+   * @return {!cast.framework.CastReceiverContext}
+   */
+  start(options) {}
+};

externs/remote-playback.js

@@ -5,8 +5,8 @@
  */
 
 /**
- * @fileoverview Externs for HTMLMediaElement related to casting which were
- * missing in the Closure compiler.
+ * @fileoverview Externs for HTMLMediaElement related to remote playback which
+ * were missing in the Closure compiler.
  *
  * @externs
  */

karma.conf.js

@@ -197,7 +197,13 @@ module.exports = (config) => {
 
     // list of files / patterns to load in the browser
     files: [
-      // Polyfills first, primarily for IE 11 and older TVs:
+      // The Cast boot file must come first, to start the SDK and respond as
+      // quickly as possible to the Cast platform.  Without this up front, we
+      // tend to see the Chromecast time out and shut down the receiver that
+      // hosts our tests.
+      'test/test/cast-boot.js',
+
+      // Polyfills before anything else, primarily for older TVs:
       //   Promise polyfill, required since we test uncompiled code on IE11
       'node_modules/es6-promise-polyfill/promise.js',
       //   Babel polyfill, required for async/await
@@ -230,9 +236,6 @@ module.exports = (config) => {
       // test utilities next, which fill in that namespace
       'test/test/util/*.js',
 
-      // Proxy cast.__platform__ methods across frames, necessary in testing
-      'proxy-cast-platform.js',
-
       // bootstrapping for the test suite last; this will load the actual tests
       'test/test/boot.js',
 
@@ -389,7 +392,6 @@ module.exports = (config) => {
         'ui/**/*.js': ['babel', 'sourcemap'],
         'test/**/*.js': ['babel', 'sourcemap'],
         'third_party/**/*.js': ['babel', 'sourcemap'],
-        'proxy-cast-platform.js': ['babel', 'sourcemap'],
       },
 
       babelPreprocessor: {

package-lock.json

@@ -5537,7 +5537,7 @@
     },
     "node_modules/karma": {
       "version": "6.4.3",
-      "resolved": "git+ssh://git@github.com/joeyparrish/karma.git#d98765e43fe801b35452fdb6cab3d1d0bac519a2",
+      "resolved": "git+ssh://git@github.com/joeyparrish/karma.git#9875e9898b999684c2b2767c34d766ab2220f351",
       "dev": true,
       "license": "MIT",
       "dependencies": {
@@ -12947,7 +12947,7 @@
       }
     },
     "karma": {
-      "version": "git+ssh://git@github.com/joeyparrish/karma.git#d98765e43fe801b35452fdb6cab3d1d0bac519a2",
+      "version": "git+ssh://git@github.com/joeyparrish/karma.git#9875e9898b999684c2b2767c34d766ab2220f351",
       "dev": true,
       "from": "karma@github:joeyparrish/karma#shaka-fixes",
       "requires": {

proxy-cast-platform.js

@@ -1,138 +0,0 @@
-/*! @license
- * Shaka Player
- * Copyright 2016 Google LLC
- * SPDX-License-Identifier: Apache-2.0
- */
-
-/**
- * @fileoverview Proxy cast platform methods across frames.  Shared between the
- * test environment and support.html.
- */
-
-/**
- * Patch Cast's cast.__platform__.canDisplayType to allow it to operate across
- * frames and origins in our testing environment.
- *
- * The Cast runtime only exposes cast.__platform__ on the top window, not
- * iframes embedded within it.  However, both Chromecast WebDriver Server in
- * our lab and the test runner Karma use iframes, and there are three different
- * origins involved: WebDriver Server's receiver at github.io, Karma's
- * top-level, and an inner frame of Karma that is raw HTML as text with no
- * origin.
- *
- * With all of these complexities, the only way to access cast.__platform__ is
- * asynchronously via postMessage.  This means all callers of
- * cast.__platform__.canDisplayType must use `await`, even though the
- * underlying method is synchronous.  If the caller is running in the top frame
- * (as in a real receiver), `await` will do no harm.  If the caller is running
- * inside our tests in Karma, the `await` is critical to access __platform__
- * via this shim.
- */
-function proxyCastCanDisplayType() {
-  if (!navigator.userAgent.includes('CrKey')) {
-    // Not Chromecast, do nothing.
-    return;
-  }
-
-  // Create the namespaces if needed.
-  if (!window.cast) {
-    window['cast'] = {};
-  }
-  if (!cast.__platform__) {
-    cast['__platform__'] = {};
-  }
-
-  if (cast.__platform__.canDisplayType) {
-    // Already exists, do nothing.
-    return;
-  }
-
-  // Create an async shim.  Calls to canDisplayType will be translated into
-  // async messages to the top frame, which will then execute the method and
-  // post a message back with results (or an error).  The resolve/reject
-  // functions for the shim's returned Promise will be stored temporarily in
-  // these maps and matched up by request ID.
-  /** @type {!Map<number, function(?)>} */
-  const resolveMap = new Map();
-  /** @type {!Map<number, function(?)>} */
-  const rejectMap = new Map();
-  /** @type {number} */
-  let nextId = 0;
-
-  /**
-   * @typedef {{
-   *   id: number,
-   *   type: string,
-   *   result: *,
-   * }}
-   */
-  let CastShimMessage;
-
-  // Listen for message events for results/errors from the top frame.
-  window.addEventListener('message', (event) => {
-    const data = /** @type {CastShimMessage} */(event['data']);
-    console.log('Received cross-frame message', data);
-
-    if (data.type == 'cast.__platform__:result') {
-      // Find the matching resolve function and resolve the promise for this
-      // request.
-      const resolve = resolveMap.get(data.id);
-      if (resolve) {
-        resolve(data.result);
-
-        // Clear both resolve and reject from the maps for this ID.
-        resolveMap.delete(data.id);
-        rejectMap.delete(data.id);
-      }
-    } else if (data.type == 'cast.__platform__:error') {
-      // Find the matching reject function and reject the promise for this
-      // request.
-      const reject = rejectMap.get(data.id);
-      if (reject) {
-        reject(data.result);
-
-        // Clear both resolve and reject from the maps for this ID.
-        resolveMap.delete(data.id);
-        rejectMap.delete(data.id);
-      }
-    }
-  });
-
-  // Shim canDisplayType to proxy the request up to the top frame.
-  cast.__platform__.canDisplayType = /** @type {?} */(castCanDisplayTypeShim);
-
-  /**
-   * @param {string} type
-   * @return {!Promise<boolean>}
-   */
-  function castCanDisplayTypeShim(type) {
-    return new Promise((resolve, reject) => {
-      // Craft a message for the top frame to execute this method for us.
-      const message = {
-        id: nextId++,
-        type: 'cast.__platform__',
-        command: 'canDisplayType',
-        args: Array.from(arguments),
-      };
-
-      // Store the resolve and reject functions so we can act on results/errors
-      // later.
-      resolveMap.set(message.id, resolve);
-      rejectMap.set(message.id, reject);
-
-      // Reject after a 5s timeout.  This can happen if we're running under an
-      // incompatible version of Chromecast WebDriver Server's receiver app.
-      setTimeout(() => {
-        reject(new Error('canDisplayType timeout!'));
-
-        // Clear both resolve and reject from the maps for this ID.
-        resolveMap.delete(message.id);
-        rejectMap.delete(message.id);
-      }, 5000);
-
-      // Send the message to the top frame.
-      console.log('Sending cross-frame message', message);
-      window.top.postMessage(message, '*');
-    });
-  }
-}

support.html

@@ -38,9 +38,10 @@
 }
 
     </style>
+    <script src="dist/cast-boot.js"></script>
     <script src="dist/shaka-player.compiled.js"></script>
-    <script src="proxy-cast-platform.js"></script>
     <script>
+
       function whenLoaded(fn) {
         // IE 9 fires DOMContentLoaded, and enters the "interactive"
         // readyState, before document.body has been initialized, so wait
@@ -74,7 +75,6 @@
       }
 
       function doTest() {
-        proxyCastCanDisplayType();
         shaka.polyfill.installAll();
 
         if (shaka.Player.isBrowserSupported()) {

test/test/boot.js

@@ -97,8 +97,29 @@ function failTestsOnUnhandledErrors() {
   // https://developer.mozilla.org/en-US/docs/Web/API/Window/error_event
   // https://developer.mozilla.org/en-US/docs/Web/API/ErrorEvent
   window.addEventListener('error', (event) => {
+    if (typeof event == 'string') {
+      // Since we moved to a flat (frameless) testing environment, we sometimes
+      // get error "events" on Chromecast where we only get the string "Script
+      // error." instead of an actual event object.  This would be consistent
+      // with an unhandled error thrown by a cross-origin script (such as the
+      // Cast SDK), but this string-only form should only be sent to the
+      // onerror callback and not the 'error' event listener.  This is both a
+      // bug in the SDK (unhandled error) and in the platform (called event
+      // listener with wrong format).  We ignore it here.
+      console.log('Suppressing error event with only string:', event);
+      return;
+    }
+
     /** @type {?} */
     const error = event['error'];
+    if (!error) {
+      // Since we moved to a flat (frameless) testing environment, we sometimes
+      // get error events on Chromecast where the error field is null.  It's not
+      // clear why.  Ignore these.
+      console.log('Suppressing error event with no error:', event);
+      return;
+    }
+
     failOnError('Unhandled error', error);
   });
 }
@@ -129,9 +150,9 @@ function disableScrollbars() {
 
     // eslint-disable-next-line no-restricted-syntax
   } catch (error) {
-    // On some platforms (Chromecast, Tizen), we are prevented from accessing
-    // the host context, even though it should be in the same origin.  Ignore
-    // errors here, so that the rest of the critical boot sequence can complete.
+    // On some platforms (Tizen), we are prevented from accessing the host
+    // context, even though it should be in the same origin.  Ignore errors
+    // here, so that the rest of the critical boot sequence can complete.
   }
 }
 
@@ -414,9 +435,6 @@ function setupTestEnvironment() {
   disableScrollbars();
   workAroundLegacyEdgePromiseIssues();
 
-  // Defined in proxy-cast-platform.js:
-  proxyCastCanDisplayType();
-
   // The spec filter callback occurs before calls to beforeAll, so we need to
   // install polyfills here to ensure that browser support is correctly
   // detected.

test/test/cast-boot.js

@@ -0,0 +1,37 @@
+/*! @license
+ * Shaka Player
+ * Copyright 2024 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+// Use indexOf() here, normally banned in favor of includes(), for
+// compatibility with the oldest devices and runtimes.
+// eslint-disable-next-line no-restricted-syntax
+if (navigator.userAgent.indexOf('CrKey') != -1) {
+  // Running in any frame of a Chromecast device.
+  // Load and activate the Cast SDK.
+  console.log('Loading Cast SDK');
+
+  const script =
+  /** @type {HTMLScriptElement} **/(document.createElement('script'));
+
+  script.src = 'https://www.gstatic.com/cast/sdk/libs/caf_receiver/v3/cast_receiver_framework.js';
+
+  // Use an anonymous function here, normally banned in favor of arrow
+  // functions, for compatibility with the oldest devices and runtimes.
+  // eslint-disable-next-line no-restricted-syntax
+  script.onload = function() {
+    cast.framework.CastReceiverContext.getInstance().start({
+      // What to show as the status of the app to senders
+      statusText: 'Shaka Player Testing',
+      // Don't shut down for a lack of sender input
+      disableIdleTimeout: true,
+      // Don't load player libraries, since we are loading Shaka here directly
+      skipPlayersLoad: true,
+    });
+
+    console.log('Cast SDK loaded');
+  };
+
+  document.head.appendChild(script);
+}