This is a port of the YoutubeExplode library from C#, most of the functions, doc comments, readme information, is taken from YoutubeExplode repository.
It used to build Youtube Downloader Flutter (A cross-platoform application to download video streams from youtube using this library & flutter)
YoutubeExplode is a library that provides an interface to query metadata of YouTube videos, playlists and channels, as well as to resolve and download video streams and closed caption tracks. Behind a layer of abstraction, the library parses raw page content and uses reverse-engineered AJAX requests to retrieve information. As it doesn't use the official API, there's also no need for an API key and there are no usage quotas.
Equatable
to easily perform equality checks YoutubeExplode
, not YoutubeClient
.srt
is not supported yet.Add the dependency to the pubspec.yaml (Check for the latest version)
youtube_explode_dart: ^1.10.4
Import the library
import 'package:youtube_explode_dart/youtube_explode_dart.dart';
The following example shows how you can extract various metadata from a YouTube video:
// You can provide either a video ID or URL as String or an instance of `VideoId`.
var video = yt.videos.get('https://youtube.com/watch?v=Dpp1sIL1m5Q'); // Returns a Video instance.
var title = video.title; // "Scamazon Prime"
var author = video.author; // "Jim Browning"
var duration = video.duration; // Instance of Duration - 0:19:48.00000
var video = yt.videos.get('https://youtube.com/watch?v=Dpp1sIL1m5Q');
var relatedVideos = await yt.videos.getRelatedVideos(video); // video must be a Video instance.
print(relatedVideos); //prints the list of related videos
// to get the next page of related videos
relatedVideos = await relatedVideos.nextPage();
If no related video is found getRelatedVideos
or nextPage
will return null.
Every YouTube video has a number of streams available. These streams may have different containers, video quality, bitrate, etc.
On top of that, depending on the content of the stream, the streams are further divided into 3 categories:
You can request the stream manifest to get available streams for a particular video:
var yt = YoutubeExplode();
var manifest = yt.videos.streamsClient.getManifest('Dpp1sIL1m5Q');
Once you get the manifest, you can filter through the streams and choose the one you're interested in downloading:
// Get highest quality muxed stream
var streamInfo = streamManifest.muxed.withHigestVideoQuality();
// ...or highest bitrate audio-only stream
var streamInfo = streamManifest.audioOnly.withHigestBitrate()
// ...or highest quality MP4 video-only stream
var streamInfo.videoOnly.where((e) => e.container == Container)
Finally, you can get the actual Stream
object represented by the metadata:
if (streamInfo != null) {
// Get the actual stream
var stream = yt.video.streamClient.get(streamInfo);
// Open a file for writing.
var file = File(filePath);
var fileStream = file.openWrite();
// Pipe all the content of the stream into the file.
await stream.pipe(fileStream);
// Close the file.
await fileStream.flush();
await fileStream.close();
}
While it may be tempting to just always use muxed streams, it's important to note that they are limited in quality. Muxed streams don't go beyond 720p30.
If you want to download the video in maximum quality, you need to download the audio-only and video-only streams separately and then mux them together on your own. There are tools like FFmpeg that let you do that.
Among other things, YoutubeExplode also supports playlists:
var yt = YoutubeExplode();
// Get playlist metadata.
var playlist = await yt.playlists.get('xxxxx');
var title = playlist.title;
var author = playlist.author;
await for (var video in yt.playlists.getVideos(playlist.id)) {
var videoTitle = video.title;
var videoAuthor = video.author;
}
var playlistVideos = await yt.playlists.getVideos(playlist.id);
// Get first 20 playlist videos.
var somePlaylistVideos = await yt.playlists.getVideos(playlist.id).take(20);
Similarly, to streams, you can extract closed captions by getting the manifest and choosing the track you're interested in:
var yt = YoutubeExplode();
var trackManifest = await yt.videos.closedCaptions.getManifest('_QdPW8JrYzQ')
var trackInfo = manifest.getByLanguage('en'); // Get english caption.
if (trackInfo != null)
{
// Get the actual closed caption track.
var track = await youtube.videos.closedCaptions.get(trackInfo);
// Get the caption displayed at 1:01
var caption = track.getByTime(Duration(seconds: 61));
var text = caption?.text; // "And the game was afoot."
}
You can easily get the video comments of a given video, the return value of commentsClient.getComments(video)
is a list-like object which behaves exactly like a List
but has an additional method nextPage()
which is used in order to get the next comments, it returns null when there are no comments to be fetched anymore.
var comments = await yt.videos.commentsClient.getComments(video);
var replies = await yt.videos.commentsClient.getReplies(comment); // Fetch the comment replies
You need to close YoutubeExplode
's http client, when done otherwise this could halt the dart process.
yt.close();
More examples available on GitHub.
Check the api documentation for additional information. You can find how most APIs can be used in the files inside the test/ folder.