Queuing

PRESTOplay exposes queue APIs on both the receiver and sender, so you can implement custom playlist behavior based on Google Cast queuing.

Receiver queue initialization

PRESTOplay implements a basic Queue. Initialize the queue on the receiver side by calling Receiver.setQueue before receiver.start(), so the Cast Application Framework (CAF) has the queue registered before it accepts sender sessions:

const player = new clpp.Player('video');
const receiver = clpp.cast.Receiver.getInstance();
const queue = clpp.cast.createCastQueue();

receiver.init(player);
receiver.setQueue(queue);
receiver.start();

Custom queue

Use cast.createCastQueue or extend cast.framework.QueueBase for custom queue lifecycle behavior. Refer to the CAF custom queue docs for implementation reference.

class CustomQueue extends cast.framework.QueueBase {
  // ...
}

const player = new clpp.Player('video');
const receiver = clpp.cast.Receiver.getInstance();
const queue = new CustomQueue();

receiver.init(player);
receiver.setQueue(queue);
receiver.start();

Receiver queue management

Once the queue is registered, call clpp.cast.Receiver.getInstance().getQueueManager() to get the CAF queue manager and use its APIs.

Sender integrations

Web SDK sender

CastProxy can forward queue commands to the receiver:

• CastProxy.queueAddItems appends new items to the end of the queue.

castProxy.queueAddItems([
  {
    media: {
      contentId: 'https://demo.cf.castlabs.com/media/prestodash/Manifest.mpd',
      contentType: 'application/dash+xml',
    },
  },
  {
    media: {
      contentId: 'https://demo.cf.castlabs.com/media/TOS/abr/Manifest_clean_sizes.mpd',
      contentType: 'application/dash+xml',
    },
  },
]);

• CastProxy.queueNextItem and CastProxy.queuePreviousItem navigate forward and backward through the queue.

Basic queue usage:

const player = new clpp.Player('video', ...);
const proxy = new clpp.cast.CastProxy(player, '<your_receiver_app_id>');

player.open({
  source: 'https://demo.cf.castlabs.com/media/prestodash/Manifest.mpd',
  type: 'application/dash+xml',
  drmProtected: false,
});

// Add queue items right after the casting session starts
player.on(clpp.events.CAST_STATUS_CHANGED, () => {
  if (proxy.isCasting()) {
    proxy.queueAddItems([
      {
        media: {
          contentId: 'https://demo.cf.castlabs.com/media/prestodash/Manifest.mpd',
          contentType: 'application/dash+xml',
        },
      },
      {
        media: {
          contentId: 'https://demo.cf.castlabs.com/media/TOS/abr/Manifest_clean_sizes.mpd',
          contentType: 'application/dash+xml',
        },
      },
    ]);
  }
});

Generic senders via custom messages

Any sender can interact with the custom queue through CAF messages:

const session = cast.framework.CastContext.getInstance().getCurrentSession();
session.sendMessage('urn:x-cast:com.google.cast.media', {
  type: 'QUEUE_INSERT',
  requestId,
  mediaSessionId: session.getMediaSession().mediaSessionId,
  items: [
    {
      media: {
        contentId: 'https://demo.cf.castlabs.com/media/TOS/abr/Manifest_clean_sizes.mpd',
        contentType: 'application/dash+xml',
      },
    },
  ],
});

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