adds method for shortened spotify url expansion

example/example.dart

@@ -12,6 +12,10 @@ void main() async {
   var credentials = SpotifyApiCredentials(keyMap['id'], keyMap['secret']);
   var spotify = SpotifyApi(credentials);
 
+  print('\nExpannd shortened spotify link of https://spotify.link/hRkBrwub9xb');
+  var longLink = await spotify.expandLink('https://spotify.link/hRkBrwub9xb');
+  print(longLink);
+
   print('\nPodcast:');
   await spotify.shows
       .get('4rOoJ6Egrf8K2IrywzwOMk')

lib/src/spotify_base.dart

@@ -158,6 +158,9 @@ abstract class SpotifyApiBase {
     );
   }
 
+  /// Expands shortened spotify [url]
+  Future<String> expandLink(String url) async => _streamedHeadImpl(url, const {});
+
   Future<String> _get(String path) {
     return _getImpl('$_baseUrl/$path', const {});
   }
@@ -174,6 +177,15 @@ abstract class SpotifyApiBase {
     return _putImpl('$_baseUrl/$path', const {}, body);
   }
 
+  Future<String> _streamedHeadImpl(
+      String url, Map<String, String> headers) async {
+    return await _requestWrapper(() async {
+      final request = http.Request('HEAD', Uri.parse(url));
+      request.headers.addAll(headers);
+      return (await _client).send(request);
+    });
+  }
+
   Future<String> _getImpl(String url, Map<String, String> headers) async {
     return await _requestWrapper(() async =>
         await (await _client).get(Uri.parse(url), headers: headers));
@@ -202,14 +214,26 @@ abstract class SpotifyApiBase {
         .put(Uri.parse(url), headers: headers, body: body));
   }
 
-  Future<String> _requestWrapper(Future<http.Response> Function() request,
+  // the reason we are using [http.BaseResponse] is because
+  // otherwise we wouldn't be able to access the redirect url from
+  // BaseResponseWithUrl
+  Future<String> _requestWrapper(Future<http.BaseResponse> Function() request,
       {retryLimit = 5}) async {
     for (var i = 0; i < retryLimit; i++) {
       while (_shouldWait) {
         await Future.delayed(Duration(milliseconds: 500));
       }
       try {
-        return handleErrors(await request());
+        var response = await request();
+
+        // distinguish between url redirect responses and body responses
+        // note, that any response that also contains a redirect url
+        // will be chosen instead of its body contents
+        // FIXME: in future releases of http2, the url is a part of the [http.Response] type
+        if (response case http.BaseResponseWithUrl(:final url)) {
+            return url.toString();
+        }
+        return handleResponseWithBody(response as http.Response);
       } on ApiRateException catch (ex) {
         if (i == retryLimit - 1) rethrow;
         print(
@@ -226,7 +250,7 @@ abstract class SpotifyApiBase {
     return SpotifyApiCredentials._fromClient(await _client);
   }
 
-  String handleErrors(http.Response response) {
+  String handleResponseWithBody(http.Response response) {
     final responseBody = utf8.decode(response.bodyBytes);
     if (response.statusCode >= 400) {
       final jsonMap = json.decode(responseBody);

pubspec.yaml

@@ -4,12 +4,12 @@ version: 0.13.1
 homepage: https://github.com/rinukkusu/spotify-dart
 
 environment:
-  sdk: '>=2.18.0 <4.0.0'
+  sdk: '>=3.0.0 <4.0.0'
 
 dependencies:
-  http: ^1.1.0
+  http: ^1.2.0
   json_annotation: ^4.8.1
-  oauth2: ^2.0.0
+  oauth2: ^2.0.2
 
 dev_dependencies:
   lints: ">=2.1.1 <4.0.0"