bilibili/flv.js · error · InvalidArgumentException

NativePlayer does't support flv MediaDataSource input!

Error message

NativePlayer does't support flv MediaDataSource input!

What it means

NativePlayer handles browser-native formats (mp4, etc.) via the HTMLMediaElement directly. Its constructor throws InvalidArgumentException when mediaDataSource.type is 'flv', since FLV demuxing requires FlvPlayer, and also rejects multipart ('segments') sources. It is a format-capability guard.

Source

Thrown at src/player/native-player.js:38

import PlayerEvents from './player-events.js';
import {createDefaultConfig} from '../config.js';
import {InvalidArgumentException, IllegalStateException} from '../utils/exception.js';

// Player wrapper for browser's native player (HTMLVideoElement) without MediaSource src. 
class NativePlayer {

    constructor(mediaDataSource, config) {
        this.TAG = 'NativePlayer';
        this._type = 'NativePlayer';
        this._emitter = new EventEmitter();

        this._config = createDefaultConfig();
        if (typeof config === 'object') {
            Object.assign(this._config, config);
        }

        if (mediaDataSource.type.toLowerCase() === 'flv') {
            throw new InvalidArgumentException('NativePlayer does\'t support flv MediaDataSource input!');
        }
        if (mediaDataSource.hasOwnProperty('segments')) {
            throw new InvalidArgumentException(`NativePlayer(${mediaDataSource.type}) doesn't support multipart playback!`);
        }

        this.e = {
            onvLoadedMetadata: this._onvLoadedMetadata.bind(this)
        };

        this._pendingSeekTime = null;
        this._statisticsReporter = null;

        this._mediaDataSource = mediaDataSource;
        this._mediaElement = null;
    }

    destroy() {
        if (this._mediaElement) {

View on GitHub (pinned to 42343088f2)

Solutions

1. Use flvjs.createPlayer(mediaDataSource) and let the factory choose: flv -> FlvPlayer, others -> NativePlayer.
2. For FLV playback with FlvPlayer, set type: 'flv' and instantiate FlvPlayer.
3. Remove explicit `new NativePlayer(...)` calls for FLV sources.

Example fix

// before
const player = new flvjs.NativePlayer({type: 'flv', url: 'stream.flv'});
// after
const player = flvjs.createPlayer({type: 'flv', url: 'stream.flv'}); // returns FlvPlayer

function createCorrectPlayer(ds) {
    if (ds && typeof ds.type === 'string' && ds.type.toLowerCase() === 'flv') {
        return flvjs.createPlayer(ds); // FlvPlayer
    }
    if (ds && Array.isArray(ds.segments)) {
        throw new Error('NativePlayer does not support multipart playback');
    }
    return flvjs.createPlayer(ds); // NativePlayer
}

function isNativeCompatibleSource(ds) {
    return !!ds && typeof ds.type === 'string' &&
        ds.type.toLowerCase() !== 'flv' &&
        !Object.prototype.hasOwnProperty.call(ds, 'segments');
}

try {
    player = new flvjs.NativePlayer(ds);
} catch (e) {
    if (/doesn't support flv MediaDataSource/.test(e.message)) {
        player = flvjs.createPlayer(ds);
    } else throw e;
}

When it happens

Trigger: new NativePlayer({type: 'flv', url: ...}) or using flvjs.createPlayer with is flv forced such that NativePlayer is selected for an flv dataSource, in the constructor (src/player/native-player.js:38).

Common situations: Explicitly instantiating NativePlayer while reusing an FLV config, a config factory that always sets type 'flv', or passing an FLV source to the wrong player class after a refactor.

Related errors

• FlvPlayer requires an flv MediaDataSource input!
• Flv: onError & onMediaInfo & onTrackMetadata & onDataAvailab
• Custom seekType specified in config but invalid customSeekHa
• Invalid seekType in config: ${config.seekType}
• Url must be a non-empty string!

AI-assisted analysis of bilibili/flv.js@42343088f2 (2026-09-01). Data as JSON: /api/errors/43778977e750f320. Report an issue: GitHub.