Implement v5 - 1

analysis_options.yaml

@@ -15,5 +15,5 @@ linter:
      - prefer_contains
 
 analyzer:
-#   exclude:
-#     - path/to/excluded/files/**
+   exclude:
+     - example\**

lib/src/channel/channel_client.dart

@@ -0,0 +1,3 @@
+class ChannelClient {
+  ChannelClient._();
+}

lib/src/exceptions/fatal_failure_exception.dart

@@ -0,0 +1,26 @@
+import 'dart:io';
+
+import 'package:http/http.dart';
+
+import 'youtube_explode_exception.dart';
+
+/// Exception thrown when a fatal failure occurs.
+class FatalFailureException implements YoutubeExplodeException {
+  final String message;
+
+  /// Initializes an instance of [FatalFailureException]
+  FatalFailureException(this.message);
+
+  /// Initializes an instance of [FatalFailureException] with an [HttpRequest]
+  FatalFailureException.httpRequest(Response response)
+      : message = '''
+Failed to perform an HTTP request to YouTube due to a fatal failure.
+In most cases, this error indicates that YouTube most likely changed something, which broke the library.
+If this issue persists, please report it on the project's GitHub page.
+Request: ${response.request}
+Response: $response
+''';
+
+  @override
+  String toString() => 'FatalFailureException: $message';
+}

lib/src/exceptions/request_limit_exceeded_exception.dart

@@ -0,0 +1,25 @@
+import 'package:http/http.dart';
+
+import 'youtube_explode_exception.dart';
+
+/// Exception thrown when a fatal failure occurs.
+class RequestLimitExceeded implements YoutubeExplodeException {
+  final String message;
+
+  /// Initializes an instance of [FatalFailureException]
+  RequestLimitExceeded(this.message);
+
+  /// Initializes an instance of [FatalFailureException] with an [HttpRequest]
+  RequestLimitExceeded.httpRequest(Response response)
+      : message = '''
+Failed to perform an HTTP request to YouTube because of rate limiting.
+This error indicates that YouTube thinks there were too many requests made from this IP and considers it suspicious.
+To resolve this error, please wait some time and try again -or- try injecting an HttpClient that has cookies for an authenticated user.
+Unfortunately, there's nothing the library can do to work around this error.
+Request: ${response.request}
+Response: $response
+''';
+
+  @override
+  String toString() => 'FatalFailureException: $message';
+}

lib/src/exceptions/youtube_explode_exception.dart

@@ -0,0 +1,5 @@
+/// Parent class for domain exceptions thrown by [YoutubeExplode]
+abstract class YoutubeExplodeException implements Exception {
+  final String message;
+  YoutubeExplodeException(this.message);
+}

lib/src/extensions/helpers_extension.dart

@@ -1,4 +1,4 @@
-import '../cipher/cipher_operations.dart';
+import '../reverse_engineering/cipher/cipher_operations.dart';
 
 /// Utility for Strings.
 extension StringUtility on String {

lib/src/reverse_engineering/cipher/cipher.dart

@@ -2,8 +2,8 @@ library youtube_explode.cipher;
 
 import 'package:http/http.dart' as http;
 
-import '../exceptions/exceptions.dart';
-import '../extensions/helpers_extension.dart';
+import '../../exceptions/exceptions.dart';
+import '../../extensions/helpers_extension.dart';
 import 'cipher_operations.dart';
 
 final _deciphererFuncNameExp = RegExp(

lib/src/reverse_engineering/responses/channel_page.dart

@@ -0,0 +1,54 @@
+import 'package:html/dom.dart';
+import 'package:html/parser.dart' as parser;
+
+class ChannelPage {
+  final Document _root;
+
+
+  bool get isOk => _root.querySelector('meta[property="og:url"]') != null;
+
+  String get channelUrl => _root
+      .querySelectorThrow('meta[property="og:url"]')
+      .getAttributeThrow('content');
+
+  String get channelId => channelId.substringAfter('channel/');
+
+  String get channelTitle => _root
+      .querySelectorThrow('meta[property="og:title"]')
+      .getAttributeThrow('content');
+
+  String get channelLogoUrl => _root
+      .querySelectorThrow('meta[property="og:image"]')
+      .getAttributeThrow('content');
+
+  ChannelPage(this._root);
+
+  ChannelPage.parse(String raw) : _root = parser.parse(raw);
+
+  static Future<ChannelPage> hello() {}
+}
+
+extension on Document {
+  Element querySelectorThrow(String selectors) {
+    var element = querySelector(selectors);
+    if (element == null) {
+      //TODO: throw
+    }
+    return element;
+  }
+}
+
+extension on Element {
+  String getAttributeThrow(String name) {
+    var attribute = attributes[name];
+    if (attribute == null) {
+      //TODO: throw
+    }
+    return attribute;
+  }
+}
+
+extension on String {
+  String substringAfter(String separator) =>
+      substring(indexOf(separator) + length);
+}

lib/src/reverse_engineering/reverse_engineering.dart

@@ -0,0 +1 @@
+export 'youtube_http_client.dart';

lib/src/reverse_engineering/youtube_http_client.dart

@@ -0,0 +1,69 @@
+import 'package:http/http.dart';
+
+class YoutubeHttpClient {
+  final Client _httpClient = Client();
+
+  /// Throws if something is wrong with the response.
+  void _validateResponse(Request request, int statusCode) {
+    if (request.url.host.endsWith('.google.com') &&
+        request.url.path.startsWith('/sorry/')) {
+      //TODO: throw RequestLimitExceededException.FailedHttpRequest(response);
+    }
+
+    if (statusCode >= 500) {
+      //TODO: TransientFailureException.FailedHttpRequest(response);
+    }
+
+    if (statusCode == 429) {
+      //TODO: throw RequestLimitExceededException.FailedHttpRequest(response);
+    }
+
+    if (statusCode >= 400) {
+      //TODO: throw FatalFailureException.FailedHttpRequest(response);
+    }
+  }
+
+  Future<Response> get(dynamic url, {Map<String, String> headers}) {
+    return _httpClient.get(url, headers: headers);
+  }
+
+  Future<Response> head(dynamic url, {Map<String, String> headers}) {
+    return _httpClient.head(url, headers: headers);
+  }
+
+  Future<String> getString(dynamic url,
+      {Map<String, String> headers, bool validate = true}) async {
+    var response = await _httpClient.get(url, headers: headers);
+
+    if (validate) {
+      _validateResponse(response.request, response.statusCode);
+    }
+
+    return response.body;
+  }
+
+  Stream<List<int>> getStream(dynamic url,
+      {Map<String, String> headers,
+        int from,
+        int to,
+        bool validate = true}) async* {
+    var request = Request('get', url);
+    request.headers['range'] = 'bytes=$from-$to';
+    var response = await request.send();
+    if (validate) {
+      _validateResponse(response.request, response.statusCode);
+    }
+    yield* response.stream;
+  }
+
+  Future<int> getContentLength(dynamic url,
+      {Map<String, String> headers, bool validate = true}) async {
+    var response = await head(url, headers: headers);
+
+    if (validate) {
+      _validateResponse(response.request, response.statusCode);
+    }
+
+    return int.parse(response.headers['content-length']);
+  }
+}

lib/src/youtube_explode_base.dart

@@ -11,6 +11,8 @@ import 'extensions/extensions.dart';
 import 'models/models.dart';
 import 'parser.dart' as parser;
 
+import 'channel/channel_client.dart';
+
 /// YoutubeExplode entry class.
 class YoutubeExplode {
   static final _regMatchExp = RegExp(r'youtube\..+?/watch.*?v=(.*?)(?:&|/|$)');
@@ -24,7 +26,7 @@ class YoutubeExplode {
 
   /// HTTP Client.
   // Visible only for extensions.
-  http.Client client;
+  final http.Client client;
 
   /// Initialize [YoutubeExplode] class and http client.
   YoutubeExplode() : client = http.Client();