Add DownloadExtension

CHANGELOG.md

@@ -42,4 +42,8 @@
 ## 0.0.10
 
 - Bug fix: Don't throw when captions are not present.
-- New extension: CaptionListExtension adding `getByTime` function.
+- New extension: CaptionListExtension adding `getByTime` function.
+
+## 0.0.11
+
+- New extension: DownloadExtension adding `downloadStream` function.

README.md

@@ -16,11 +16,11 @@ This doesn't require an API key and has no usage quotas.
 - Provides static methods to validate IDs and to parse IDs from URLs
 - No need for an API key and no usage quotas
 - All model extend `Equatable` to easily perform equality checks 
+- Download Stream
 
 ## Features not implemented
 
 - Adaptive streams
-- Download streams functions.
 
 ## Differences from YoutubeExplode
 
@@ -103,13 +103,20 @@ You need to close `YoutubeExplode`'s http client when done otherwise this could
 yt.close();
 ```
 
+
+# Examples:
+
+Available on [GitHub][Examples]
+
 ---
+
 Check the [api doc][API] for additional information.
-More features are provided thru extensions.
+More features are provided through extensions.
 
 [YoutubeExplode]: https://github.com/Tyrrrz/YoutubeExplode/
 
 [Video]: https://pub.dev/documentation/youtube_explode_dart/latest/youtube_explode/Video-class.html
 [MediaStreamsInfoSet]: https://pub.dev/documentation/youtube_explode_dart/latest/youtube_explode/MediaStreamInfoSet-class.html
 [VidExample]: https://github.com/Hexer10/youtube_explode_dart/blob/master/example/video_download.dart
-[API]: https://pub.dev/documentation/youtube_explode_dart/latest/youtube_explode/youtube_explode-library.html
+[API]: https://pub.dev/documentation/youtube_explode_dart/latest/youtube_explode/youtube_explode-library.html
+[Examples][https://github.com/Hexer10/youtube_explode_dart/tree/master/example]

example/video_download.dart

@@ -3,7 +3,6 @@ import 'dart:io';
 
 import 'package:dart_console/dart_console.dart';
 import 'package:youtube_explode_dart/youtube_explode_dart.dart';
-import 'package:http/http.dart' as http;
 
 // Initialize the YoutubeExplode instance.
 final yt = YoutubeExplode();
@@ -12,7 +11,7 @@ final console = Console();
 
 Future<void> main() async {
   console.writeLine('Type the video id or url: ');
-  
+
   var url = stdin.readLineSync().trim();
 
   // Get the video url.
@@ -56,14 +55,12 @@ Future<void> download(String id) async {
   var file = File('downloads/$fileName');
 
   // Create the StreamedRequest to track the download status.
-  var req = http.Request('get', audio.url);
-  var resp = await req.send();
 
   // Open the file in appendMode.
   var output = file.openWrite(mode: FileMode.writeOnlyAppend);
 
   // Track the file download status.
-  var len = resp.contentLength;
+  var len = audio.size;
   var count = 0;
   var oldProgress = -1;
 
@@ -75,7 +72,7 @@ Future<void> download(String id) async {
   console.write(msg);
 
   // Listen for data received.
-  return resp.stream.listen((data) {
+  await for (var data in audio.downloadStream()) {
     count += data.length;
     var progress = ((count / len) * 100).round();
     if (progress != oldProgress) {
@@ -84,7 +81,7 @@ Future<void> download(String id) async {
       oldProgress = progress;
     }
     output.add(data);
-  }, onDone: () async {
-    await output.close();
-  }).asFuture();
+  }
+  console.writeLine();
+  await output.close();
 }

lib/src/extensions/download_extension.dart

@@ -0,0 +1,27 @@
+import 'dart:async';
+import 'dart:io';
+
+import 'package:http/http.dart' as http;
+
+import '../models/models.dart';
+
+/// Download extension for [MediaStreamInfo]
+extension DownloadExtension on MediaStreamInfo {
+  static final _rateBypassExp = RegExp('ratebypass[=/]yes');
+
+  /// Returns the stream of this media stream object.
+  /// The download is split in multiple requests using the `range` parameter.
+  ///
+  Stream<List<int>> downloadStream() async* {
+    var maxSize = _rateBypassExp.hasMatch(url.toString()) ? 9898989 : size + 1;
+    var total = 0;
+
+    for (var i = 1; total < size; i++) {
+      var req = http.Request('get', url);
+      req.headers[HttpHeaders.rangeHeader] = 'bytes=$total-${total + maxSize}';
+      var resp = await req.send();
+      yield* resp.stream;
+      total += maxSize + 1;
+    }
+  }
+}

lib/src/extensions/extensions.dart

@@ -1,5 +1,6 @@
 export 'caption_extension.dart';
 export 'channel_extension.dart';
+export 'download_extension.dart';
 export 'helpers_extension.dart';
 export 'playlist_extension.dart';
 export 'search_extension.dart';

pubspec.yaml

@@ -1,6 +1,6 @@
 name: youtube_explode_dart
 description: A port in dart of the youtube explode library. Support serveral API functions.
-version: 0.0.10
+version: 0.0.11
 homepage: https://github.com/Hexer10/youtube_explode_dart
 
 environment: