Queue Manager
The QueueManager allows you to manage a playlist of media items in Shaka Player,
handling automatic progression, repeat modes, and preloading of adjacent items to
minimize transition latency.
It is automatically created and associated with a shaka.Player instance — you
do not need to instantiate it directly.
Basic Usage
Retrieve the QueueManager from a player instance and insert items to play:
async function initPlayer() {
const video = document.getElementById('video');
const player = new shaka.Player();
await player.attach(video);
const queueManager = player.getQueueManager();
// Insert one or more items into the queue
queueManager.insertItems([
{ manifestUri: 'https://example.com/video1/dash.mpd' },
{ manifestUri: 'https://example.com/video2/dash.mpd' },
{ manifestUri: 'https://example.com/video3/dash.mpd' },
]);
// Start playback from the first item
await queueManager.playItem(0);
}
Each item in the queue is a QueueItem object. At minimum it requires a
manifestUri, but it also accepts optional fields:
{
manifestUri: 'https://example.com/video.mpd', // Required
startTime: 30, // Optional: start offset in seconds
mimeType: 'application/dash+xml', // Optional: hint for the player
config: { /* shaka.extern.PlayerConfiguration */ }, // Optional: per-item config
preloadManager: null, // Optional: pre-built PreloadManager
extraText: [...], // Optional: additional text tracks
extraThumbnail: [...], // Optional: additional thumbnail tracks
extraChapter: [...], // Optional: additional chapter tracks
metadata: { /* shaka.extern.QueueItemMetadata */ }, // Optional: display metadata
}
Navigating the Queue
You can jump to any item by index, and inspect the current state of the queue at any time:
// Play the third item (zero-based index)
await queueManager.playItem(2);
// Get the currently playing item
const currentItem = queueManager.getCurrentItem();
console.log('Now playing:', currentItem.manifestUri);
// Get the current index
const index = queueManager.getCurrentItemIndex();
// Get a snapshot of all items in the queue
const allItems = queueManager.getItems();
console.log(`Queue has ${allItems.length} items`);
playItem throws a shaka.util.Error with code QUEUE_INDEX_OUT_OF_BOUNDS
if the provided index is out of range.
Repeat Modes
The QueueManager supports three repeat modes, configured via
queueManager.configure():
queueManager.configure({
repeatMode: shaka.config.RepeatMode.ALL, // Repeat the whole queue
});
| Mode | Behaviour |
|---|---|
shaka.config.RepeatMode.OFF |
Playback stops after the last item. |
shaka.config.RepeatMode.SINGLE |
The current item loops indefinitely. |
shaka.config.RepeatMode.ALL |
The queue loops back to the first item after the last. |
The default mode is OFF.
Preloading Adjacent Items
To reduce the transition delay between items, the QueueManager can
automatically preload the next item as the current one approaches its end, and
optionally preserve a preload of the previous item in case the user seeks back.
queueManager.configure({
repeatMode: shaka.config.RepeatMode.ALL,
// Start preloading the next item when this many seconds remain in the current one
preloadNextUrlWindow: 30,
// Save a preload of the previous item when advancing forward
preloadPrevItem: true,
});
When preloadNextUrlWindow is set to a positive value, the manager listens to
the playback position and triggers a player.preload() call automatically.
You do not need to manage this yourself.
If preloadPrevItem is true, navigating to the next item will internally
call player.unloadAndSavePreload() on the current one, so going back is
faster. This only works when the player is in MEDIA_SOURCE load mode.
Listening to Queue Events
The QueueManager extends FakeEventTarget and dispatches events you can
subscribe to:
queueManager.addEventListener('currentitemchanged', () => {
const item = queueManager.getCurrentItem();
console.log('Now playing:', item.manifestUri);
});
queueManager.addEventListener('itemsinserted', () => {
console.log('Items added. Queue length:', queueManager.getItems().length);
});
queueManager.addEventListener('itemsremoved', () => {
console.log('Queue cleared.');
});
| Event | Fired when |
|---|---|
currentitemchanged |
playItem() is called with a different index than the current one. |
itemsinserted |
insertItems() is called. |
itemsremoved |
removeAllItems() is called. |
Adding Extra Tracks per Item
Each QueueItem can carry additional text, thumbnail, or chapter tracks that
are added to the player automatically once streaming begins:
queueManager.insertItems([
{
manifestUri: 'https://example.com/video.mpd',
extraText: [
{
uri: 'https://example.com/subtitles-en.vtt',
language: 'en',
kind: 'subtitle',
mime: 'text/vtt',
},
],
extraThumbnail: [
'https://example.com/thumbnails.vtt',
],
extraChapter: [
{
uri: 'https://example.com/chapters-en.vtt',
language: 'en',
mime: 'text/vtt',
},
],
},
]);
All extra tracks for a given item are added in parallel after the streaming
event fires, so they do not block initial playback.
Item Metadata
Each QueueItem accepts an optional metadata field of type
shaka.extern.QueueItemMetadata. It has two well-known properties —
title and poster — and supports any additional arbitrary properties
your application needs (they are not type-checked by Shaka).
queueManager.insertItems([
{
manifestUri: 'https://example.com/video.mpd',
metadata: {
title: 'My Awesome Video',
poster: 'https://example.com/poster.jpg',
// Any extra application-level data is allowed:
description: 'An optional description for your UI',
durationSeconds: 3600,
},
},
]);
You can read the metadata back from getCurrentItem() to drive your own UI
(e.g. update a title bar or thumbnail while the item changes):
queueManager.addEventListener('currentitemchanged', () => {
const item = queueManager.getCurrentItem();
if (item?.metadata) {
document.getElementById('title').textContent = item.metadata.title ?? '';
document.getElementById('poster').src = item.metadata.poster ?? '';
}
});
Note: metadata is purely application-side data. Shaka Player does not read
or use it internally.
Per-item Player Configuration
If different items in your queue require different player settings (e.g.
different DRM configurations or ABR constraints), you can attach a config
object to each QueueItem. The manager will call player.resetConfiguration()
followed by player.configure(item.config) before loading that item:
queueManager.insertItems([
{
manifestUri: 'https://example.com/clear.mpd',
},
{
manifestUri: 'https://example.com/protected.mpd',
config: {
drm: {
servers: {
'com.widevine.alpha': 'https://example.com/license',
},
},
},
},
]);
Loading an M3U Playlist
loadFromM3uPlaylist() lets you populate the queue from a remote M3U or M3U8
playlist in one call. The method fetches the file using the player's own
networking engine (so request filters, credentials, and retry parameters all
apply), parses every stream entry, and inserts the resulting items into the
queue.
// Load a playlist and start playing the first channel immediately.
await queueManager.loadFromM3uPlaylist(
'https://example.com/channels.m3u',
/* playOnLoad= */ true,
);
The second argument, playOnLoad, is optional and defaults to false. When
true, playItem(0) is called automatically once the items have been
inserted.
// Load a playlist without starting playback — useful when you want to
// inspect or filter the items before choosing which one to play.
await queueManager.loadFromM3uPlaylist('https://example.com/channels.m3u');
const items = queueManager.getItems();
const newsIndex = items.findIndex(
(item) => item.metadata?.groupTitle === 'News',
);
if (newsIndex >= 0) {
await queueManager.playItem(newsIndex);
}
EXTINF attributes and item metadata
The parser supports the Extended M3U format (#EXTM3U / #EXTINF) with the
tvg-* and group-title attributes commonly found in IPTV playlists. All
attributes are copied into the item's metadata object using their original
hyphenated names (e.g. tvg-id, tvg-name, group-title). Two standard
QueueItemMetadata aliases are also set on top:
| Playlist attribute | metadata property |
Notes |
|---|---|---|
tvg-name |
tvg-name + title |
title falls back to the display name. |
tvg-logo |
tvg-logo + poster |
|
tvg-id |
tvg-id |
Also used for deduplication (see below). |
tvg-language |
tvg-language |
|
tvg-country |
tvg-country |
|
tvg-url |
tvg-url |
EPG (Electronic Programme Guide) feed URL. |
group-title |
group-title |
|
| Display name | displayTitle |
The text after the last comma in #EXTINF. |
| (any other) | (original name) | Unknown attributes are preserved as-is. |
A typical IPTV entry and the metadata it produces:
#EXTINF:-1 tvg-id="bbc1" tvg-name="BBC One" tvg-logo="https://example.com/bbc1.png" tvg-language="English" tvg-country="GB" group-title="Entertainment",BBC One HD
https://example.com/bbc1/stream.m3u8
{
manifestUri: 'https://example.com/bbc1/stream.m3u8',
metadata: {
// Standard QueueItemMetadata aliases
title: 'BBC One', // from tvg-name
poster: 'https://example.com/bbc1.png', // from tvg-logo
// Raw attribute names, exactly as in the playlist
'tvg-id': 'bbc1',
'tvg-name': 'BBC One',
'tvg-logo': 'https://example.com/bbc1.png',
'tvg-language': 'English',
'tvg-country': 'GB',
'group-title': 'Entertainment',
// Extra helper added by the parser
displayTitle: 'BBC One HD', // raw text after the last comma
},
}
You can use metadata['group-title'] to build a channel-group UI, or
metadata['tvg-url'] to load EPG schedule data for the currently playing
channel:
queueManager.addEventListener('currentitemchanged', () => {
const item = queueManager.getCurrentItem();
if (item?.metadata) {
titleEl.textContent = item.metadata.title ?? '';
posterEl.src = item.metadata.poster ?? '';
groupEl.textContent = item.metadata['group-title'] ?? '';
}
});
Duplicate channel handling
Channels that share the same tvg-id value are automatically deduplicated:
only the first occurrence is kept, and subsequent entries with the same id are
silently dropped. Channels without a tvg-id are always included regardless
of whether their stream URL appears more than once.
Note: loadFromM3uPlaylist() uses RequestType.PLAYLIST and the
manifest.retryParameters from the current player configuration. If the
playlist URL requires custom headers or credentials, configure them via a
request filter before calling this method.
Clearing the Queue
To stop playback and remove all items from the queue:
await queueManager.removeAllItems();
This unloads the player, destroys any active or pending PreloadManager
instances, and resets the current index to -1.