websocket - Chromecast 接收器应用程序错误：'[goog.net.WebSocket] WebSocket 意外断开连接：未定义'

Question

在 chromecast 中创建接收器应用程序时，我们遇到了一个问题：

[goog.net.WebSocket] WebSocket 意外断开：未定义

cast_receiver_framework.js:507 WebSocket 连接到“ws://localhost:8008/v2/ipc”失败：连接建立错误：net::ERR_CONNECTION_REFUSED

我们的接收器具有简单的代码，如 chromecast 文档中 CAF 接收器提供的示例：

const context = cast.framework.CastReceiverContext.getInstance();
const playerManager = context.getPlayerManager();
const playbackConfig = new cast.framework.PlaybackConfig();
// Customize the license url for playback
playbackConfig.licenseUrl = 'https://wv-keyos.licensekeyserver.com/';
playbackConfig.protectionSystem = cast.framework.ContentProtection.WIDEVINE;
playbackConfig.licenseRequestHandler = requestInfo => {
  requestInfo.withCredentials = true;
  requestInfo.headers = {
    'customdata': '<customdata>'
  };
};
context.getPlayerManager().setMediaPlaybackInfoHandler((loadRequest, playbackConfig) => {
  if (loadRequest.media.customData && loadRequest.media.customData.licenseUrl) {
    playbackConfig.licenseUrl = loadRequest.media.customData.licenseUrl;
  }
  return playbackConfig;
});


function makeRequest (method, url) {
  return new Promise(function (resolve, reject) {
    var xhr = new XMLHttpRequest();
    xhr.open(method, url);
    xhr.onload = function () {
      if (this.status >= 200 && this.status < 300) {
        resolve(JSON.parse(xhr.response));
      } else {
        reject({
          status: this.status,
          statusText: xhr.statusText
        });
      }
    };
    xhr.onerror = function () {
      reject({
        status: this.status,
        statusText: xhr.statusText
      });
    };
    xhr.send();
  });
}

playerManager.setMessageInterceptor(
  cast.framework.messages.MessageType.LOAD,
  request => {
    castDebugLogger.info('MyAPP.LOG', 'Intercepting LOAD request');

    if (request.media && request.media.entity) {
      request.media.contentId = request.media.entity;
    }

    return new Promise((resolve, reject) => {

      if(request.media.contentType == 'video/mp4') {
        return resolve(request);
      }

      // Fetch content repository by requested contentId
      makeRequest('GET', 'https://tse-summit.firebaseio.com/content.json?orderBy=%22$key%22&equalTo=%22'+ request.media.contentId + '%22')
        .then(function (data) {
          var item = data[request.media.contentId];
          if(!item) {
            // Content could not be found in repository
            castDebugLogger.error('MyAPP.LOG', 'Content not found');
            reject();
          } else {
            // Adjusting request to make requested content playable
            request.media.contentId = item.stream.hls;
            request.media.contentType = 'application/x-mpegurl';
            castDebugLogger.warn('MyAPP.LOG', 'Playable URL:', request.media.contentId);

            // Add metadata
            var metadata = new cast.framework.messages.MovieMediaMetadata();
            metadata.metadataType = cast.framework.messages.MetadataType.MOVIE;
            metadata.title = item.title;
            metadata.subtitle = item.author;

            request.media.metadata = metadata;
            resolve(request);
          }
      });
    });
  });

/** Debug Logger **/
const castDebugLogger = cast.debug.CastDebugLogger.getInstance();

// Enable debug logger and show a warning on receiver
// NOTE: make sure it is disabled on production
castDebugLogger.setEnabled(false);

playerManager.addEventListener(
  cast.framework.events.category.CORE,
  event => {
      castDebugLogger.info('ANALYTICS', 'CORE EVENT:', event);
});

// Set verbosity level for custom tags
castDebugLogger.loggerLevelByTags = {
  'MyAPP.LOG': cast.framework.LoggerLevel.WARNING,
  'ANALYTICS': cast.framework.LoggerLevel.INFO,
};

/** Optimizing for smart displays **/
const playerData = new cast.framework.ui.PlayerData();
const playerDataBinder = new cast.framework.ui.PlayerDataBinder(playerData);
const touchControls = cast.framework.ui.Controls.getInstance();

let browseItems = getBrwoseItems();

function getBrwoseItems() {
  let data = '"video": { \
    <Encrypted Video>
    }, \
    "title": "Big Buck Bunny" \
  }';


  let browseItems = [];

  for (let key in data) {
    let item = new cast.framework.ui.BrowseItem();
    item.entity = key;
    item.title = data[key].title;
    item.subtitle = data[key].description;
    item.image = new cast.framework.messages.Image(data[key].poster);
    item.imageType = cast.framework.ui.BrowseImageType.MOVIE;
    browseItems.push(item);
  }
  return browseItems;
}

let browseContent = new cast.framework.ui.BrowseContent();
browseContent.title = 'Up Next';
browseContent.items = browseItems;
browseContent.targetAspectRatio =
  cast.framework.ui.BrowseImageAspectRatio.LANDSCAPE_16_TO_9;
playerDataBinder.addEventListener(
  cast.framework.ui.PlayerDataEventType.MEDIA_CHANGED,
  (e) => {
    if (!e.value) return;

    // Clear default buttons and re-assign
    touchControls.clearDefaultSlotAssignments();
    touchControls.assignButton(
      cast.framework.ui.ControlsSlot.SLOT_1,
      cast.framework.ui.ControlsButton.SEEK_BACKWARD_30
    );

    // Media browse
    touchControls.setBrowseContent(browseContent);
  });

context.start({playbackConfig: playbackConfig});

此代码从发件人那里获取输入，但即使发件人具有应用程序 ID，它也会显示相同的消息。