Code reformatting & refactoring.

Throw exception on error code 403.

CHANGELOG.md

@@ -65,4 +65,8 @@
 
 - Workaround (#15): Now when a video is not available a `VideoUnavailable` exception is thrown
 - Removed disable_polymer parameter when requests ( https://github.com/Tyrrrz/YoutubeExplode/issues/341 )
-- Removed `dart:io` dependency
+- Removed `dart:io` dependency
+
+## 0.0.16
+
+- When a video is not available(403) a `VideoStreamUnavailableException` 

README.md

@@ -119,4 +119,4 @@ More features are provided through extensions.
 [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
-[Examples][https://github.com/Hexer10/youtube_explode_dart/tree/master/example]
+[Examples]: [https://github.com/Hexer10/youtube_explode_dart/tree/master/example]

lib/src/exceptions/exceptions.dart

@@ -2,5 +2,6 @@ library youtube_explode.exceptions;
 
 export 'unrecognized_structure_exception.dart';
 export 'video_requires_purchase_exception.dart';
+export 'video_stream_unavailable_exception.dart';
 export 'video_unavailable_exception.dart';
 export 'video_unplayable_exception.dart';

lib/src/exceptions/video_stream_unavailable_exception.dart

@@ -0,0 +1,20 @@
+
+
+/// Thrown when a video stream is not available
+/// and returns a status code not equal to 200 OK.
+class VideoStreamUnavailableException implements Exception {
+
+  /// The returned status code.
+  final int statusCode;
+
+  /// Url
+  final Uri url;
+
+  /// Initializes an instance of [VideoStreamUnavailableException]
+  VideoStreamUnavailableException(this.statusCode, this.url);
+
+  @override
+  String toString() => 'VideoStreamUnavailableException: '
+      'The video stream in not availble (status code: $statusCode).\n'
+      'Url: $url';
+}

lib/src/extensions/channel_extension.dart

@@ -22,11 +22,11 @@ extension ChannelExtension on YoutubeExplode {
           channelId, 'channelId', 'Invalid YouTube channel id');
     }
 
-    var channelPageHtml = await getChannelPage(channelId);
-    var channelTitle = channelPageHtml
+    var channelPage = await getChannelPage(channelId);
+    var channelTitle = channelPage
         .querySelector('meta[property="og:title"]')
         .attributes['content'];
-    var channelImage = channelPageHtml
+    var channelImage = channelPage
         .querySelector('meta[property="og:image"]')
         .attributes['content'];
 
@@ -34,18 +34,20 @@ extension ChannelExtension on YoutubeExplode {
   }
 
   /// Get a channel id from a username.
-  /// Might not work properly.
+  /// Returns null if the username is not found.
   Future<String> getChannelId(String username) async {
     if (!validateUsername(username)) {
       throw ArgumentError.value(
           username, 'username', 'Invalid YouTube username');
     }
 
-    var userPageHtml = await _getUserPageHtml(username);
+    var userPage = await _getUserPage(username);
+    if (userPage == null) {
+      return null;
+    }
 
-    var channelUrl = userPageHtml
-        .querySelector('meta[property="og:url"]')
-        .attributes['content'];
+    var channelUrl =
+        userPage.querySelector('meta[property="og:url"]').attributes['content'];
 
     return channelUrl.replaceFirst('/channel/', '');
   }
@@ -85,11 +87,14 @@ extension ChannelExtension on YoutubeExplode {
     return html.parse(raw);
   }
 
-  Future<Document> _getUserPageHtml(String username) async {
+  Future<Document> _getUserPage(String username) async {
     var url = 'https://www.youtube.com/user/$username?hl=en';
-    var raw = (await client.get(url)).body;
+    var req = await client.get(url);
+    if (req.statusCode != 200) {
+      return null;
+    }
 
-    return html.parse(raw);
+    return html.parse(req);
   }
 
   /// Returns true if [username] is a valid Youtube username.

lib/src/extensions/download_extension.dart

@@ -2,6 +2,7 @@ import 'dart:async';
 
 import 'package:http/http.dart' as http;
 
+import '../exceptions/exceptions.dart';
 import '../models/models.dart';
 
 /// Download extension for [MediaStreamInfo]
@@ -12,6 +13,11 @@ extension DownloadExtension on MediaStreamInfo {
   /// The download is split in multiple requests using the `range` parameter.
   ///
   Stream<List<int>> downloadStream() async* {
+    var req = await http.head(url);
+    if (req.statusCode != 200) {
+      throw VideoStreamUnavailableException(req.statusCode, url);
+    }
+
     var maxSize = _rateBypassExp.hasMatch(url.toString()) ? 9898989 : size + 1;
     var total = 0;
 

lib/src/extensions/helpers_extension.dart

@@ -21,7 +21,7 @@ extension StringUtility on String {
 
 /// List decipher utility.
 extension ListDecipher on List<CipherOperation> {
-  /// Apply the every CipherOperation on the [signature]
+  /// Apply every CipherOperation on the [signature]
   String decipher(String signature) {
     for (var operation in this) {
       signature = operation.decipher(signature);

lib/src/youtube_explode_base.dart

@@ -203,8 +203,7 @@ class YoutubeExplode {
   }
 
   Future<PlayerConfiguration> _getPlayerConfigEmbed(String videoId) async {
-    var req = await client.get(
-            'https://www.youtube.com/embed/$videoId?&hl=en');
+    var req = await client.get('https://www.youtube.com/embed/$videoId?&hl=en');
     if (req.statusCode != 200) {
       return null;
     }
@@ -297,17 +296,17 @@ class YoutubeExplode {
   }
 
   Future<PlayerConfiguration> _getPlayerConfigWatchPage(String videoId) async {
-    var videoWatchPageHtml = await getVideoWatchPage(videoId);
-    if (videoWatchPageHtml == null) {
+    var videoWatchPage = await getVideoWatchPage(videoId);
+    if (videoWatchPage == null) {
       return null;
     }
-    var playerConfigScript = videoWatchPageHtml
+    var playerConfigScript = videoWatchPage
         .querySelectorAll('script')
         .map((e) => e.text)
         .firstWhere((e) => e.contains('ytplayer.config ='));
     if (playerConfigScript == null) {
       var errorReason =
-          videoWatchPageHtml.querySelector('#unavailable-message').text.trim();
+          videoWatchPage.querySelector('#unavailable-message').text.trim();
       throw VideoUnplayableException(videoId, errorReason);
     }
 
@@ -458,8 +457,7 @@ class YoutubeExplode {
 
   /// Returns the video watch page document.
   Future<Document> getVideoWatchPage(String videoId) async {
-    var url =
-        'https://youtube.com/watch?v=$videoId&bpctr=9999999999&hl=en';
+    var url = 'https://youtube.com/watch?v=$videoId&bpctr=9999999999&hl=en';
     var req = await client.get(url);
     if (req.statusCode != 200) {
       return null;

pubspec.yaml

@@ -1,6 +1,6 @@
 name: youtube_explode_dart
 description: A port in dart of the youtube explode library. Supports several API functions.
-version: 0.0.15
+version: 0.0.16
 homepage: https://github.com/Hexer10/youtube_explode_dart
 
 environment: