Fix JWT and add test

lib/src/model/jwt.dart

@@ -236,6 +236,9 @@ sealed class SpinifyJWT {
   /// Creates JWT from [secret] (with HMAC-SHA256 algorithm)
   /// and current payload.
   String encode(String secret);
+
+  /// Creates a JSON representation of payload.
+  Map<String, Object?> toJson();
 }
 
 final class _SpinifyJWTImpl extends SpinifyJWT {
@@ -256,28 +259,30 @@ final class _SpinifyJWTImpl extends SpinifyJWT {
   }) : super._();
 
   factory _SpinifyJWTImpl.decode(String jwt, [String? secret]) {
-    // Разделение токена на составляющие части
+    // Split token into parts
     var parts = jwt.split('.');
     if (parts.length != 3) {
+      // coverage:ignore-line
       throw const FormatException(
           'Invalid token format, expected 3 parts separated by "."');
     }
     final <String>[encodedHeader, encodedPayload, encodedSignature] = parts;
 
     if (secret != null) {
-      // Вычисление подписи
+      // Compute signature
       final key = utf8.encode(secret); // Your 256 bit secret key
       final bytes = utf8.encode('$encodedHeader.$encodedPayload');
-      var hmacSha256 = Hmac(sha256, key); // HMAC-SHA256
-      var digest = hmacSha256.convert(bytes);
-
-      // Кодирование подписи
-      var computedSignature = base64Url.encode(digest.bytes);
+      final hmacSha256 = Hmac(sha256, key); // HMAC-SHA256
+      final digest = hmacSha256.convert(bytes);
+      final computedSignature = const _UnpaddedBase64Converter()
+          .convert(base64Url.encode(digest.bytes));
 
-      // Сравнение подписи в токене с вычисленной подписью
+      // Check signature equality
+      // coverage:ignore-start
       if (computedSignature != encodedSignature) {
         throw const FormatException('Invalid token signature');
       }
+      // coverage:ignore-end
     }
 
     Map<String, Object?> payload;
@@ -286,10 +291,12 @@ final class _SpinifyJWTImpl extends SpinifyJWT {
           .fuse<String>(const Utf8Decoder())
           .fuse<Map<String, Object?>>(
               const JsonDecoder().cast<String, Map<String, Object?>>())
-          .convert(encodedPayload);
+          .convert(const _NormilizeBase64Converter().convert(encodedPayload));
     } on Object catch (_, stackTrace) {
+      // coverage:ignore-start
       Error.throwWithStackTrace(
           const FormatException('Can\'t decode token payload'), stackTrace);
+      // coverage:ignore-end
     }
     try {
       return _SpinifyJWTImpl(
@@ -310,8 +317,10 @@ final class _SpinifyJWTImpl extends SpinifyJWT {
         expireAt: payload['expire_at'] as int?,
       );
     } on Object catch (_, stackTrace) {
+      // coverage:ignore-start
       Error.throwWithStackTrace(
           const FormatException('Invalid token payload data'), stackTrace);
+      // coverage:ignore-end
     }
   }
 
@@ -402,6 +411,23 @@ final class _SpinifyJWTImpl extends SpinifyJWT {
     return '$encodedHeader.$encodedPayload.$encodedSignature';
   }
 
+  @override
+  Map<String, Object?> toJson() => <String, Object?>{
+        'sub': sub,
+        if (channel != null) 'channel': channel,
+        if (exp != null) 'exp': exp,
+        if (iat != null) 'iat': iat,
+        if (jti != null) 'jti': jti,
+        if (aud != null) 'aud': aud,
+        if (iss != null) 'iss': iss,
+        if (info != null) 'info': info,
+        if (b64info != null) 'b64info': b64info,
+        if (channels != null) 'channels': channels,
+        if (subs != null) 'subs': subs,
+        if (meta != null) 'meta': meta,
+        if (expireAt != null) 'expireAt': expireAt,
+      };
+
   @override
   String toString() => 'SpinifyJWT{sub: $sub}';
 }
@@ -418,3 +444,14 @@ class _UnpaddedBase64Converter extends Converter<String, String> {
     return input;
   }
 }
+
+/// A converter thats normalizes Base64-encoded strings
+class _NormilizeBase64Converter extends Converter<String, String> {
+  const _NormilizeBase64Converter();
+
+  @override
+  String convert(String input) {
+    final padding = (4 - input.length % 4) % 4;
+    return input + '=' * padding;
+  }
+}

pubspec.yaml

@@ -56,7 +56,6 @@ dependencies:
   fixnum: ^1.1.0
   stack_trace: ^1.11.0
 
-
 dev_dependencies:
   build_runner: ^2.4.6
   pubspec_generator: ^4.0.0

test/unit/jwt_test.dart

@@ -0,0 +1,55 @@
+// ignore_for_file: prefer_const_constructors
+
+import 'package:spinify/spinify.dart';
+import 'package:test/test.dart';
+
+void main() {
+  group('JWT', () {
+    test('Create', () {
+      expect(() => SpinifyJWT(sub: 'sub'), returnsNormally);
+    });
+
+    test('Encode_and_decode', () {
+      final jwt = SpinifyJWT(
+        sub: 'sub',
+        channel: 'channel',
+        iat: 1234567890,
+        exp: 1234567890,
+        iss: 'iss',
+        aud: 'aud',
+        jti: 'jti',
+        expireAt: 1234567890,
+        b64info: 'b64info',
+        channels: const <String>[
+          'channel1',
+          'channel2',
+        ],
+        subs: const <String, Object?>{},
+        info: const <String, Object?>{},
+        meta: const <String, Object?>{},
+      );
+      expect(jwt, isA<SpinifyJWT>());
+      expect(jwt.toString(), equals('SpinifyJWT{sub: ${jwt.sub}}'));
+      final encoded = jwt.encode('secret');
+      expect(encoded, isA<String>());
+      final decoded = SpinifyJWT.decode(encoded, 'secret');
+      expect(
+        decoded,
+        isA<SpinifyJWT>()
+            .having((e) => e.sub, 'sub', jwt.sub)
+            .having((e) => e.channel, 'channel', jwt.channel)
+            .having((e) => e.iat, 'iat', jwt.iat)
+            .having((e) => e.exp, 'exp', jwt.exp)
+            .having((e) => e.iss, 'iss', jwt.iss)
+            .having((e) => e.aud, 'aud', jwt.aud)
+            .having((e) => e.jti, 'jti', jwt.jti)
+            .having((e) => e.expireAt, 'expireAt', jwt.expireAt)
+            .having((e) => e.b64info, 'b64info', jwt.b64info)
+            .having((e) => e.channels, 'channels', jwt.channels)
+            .having((e) => e.subs, 'subs', jwt.subs),
+      );
+      expect(decoded.toJson(), equals(jwt.toJson()));
+      expect(decoded.toString(), equals(jwt.toString()));
+    });
+  });
+}

test/unit/spinify_test.dart

@@ -234,7 +234,9 @@ void main() {
                       greaterThan(Int64.ZERO),
                     ),
                   ]));
-              client.close();
+              client
+                ..newSubscription('channel')
+                ..close();
               async.elapse(client.config.timeout);
               expect(
                   client.metrics,
@@ -261,8 +263,14 @@ void main() {
                     ),
                   ]));
               expect(() => client.metrics.toString(), returnsNormally);
+              expect(client.metrics.toString(), equals('SpinifyMetrics{}'));
               expect(() => client.metrics.toJson(), returnsNormally);
               expect(client.metrics.toJson(), isA<Map<String, Object?>>());
+              expect(client.metrics.channels, hasLength(2));
+              expect(
+                  client.metrics.channels['channel'],
+                  isA<SpinifyMetrics$Channel>().having((c) => c.toString(),
+                      'subscriptions', equals(r'SpinifyMetrics$Channel{}')));
             }));
   });
 }

test/unit_test.dart

@@ -1,6 +1,7 @@
 import 'package:test/test.dart';
 
 import 'unit/config_test.dart' as config_test;
+import 'unit/jwt_test.dart' as jwt_test;
 import 'unit/logs_test.dart' as logs_test;
 import 'unit/server_subscription_test.dart' as server_subscription_test;
 import 'unit/spinify_test.dart' as spinify_test;
@@ -11,5 +12,6 @@ void main() {
     config_test.main();
     spinify_test.main();
     server_subscription_test.main();
+    jwt_test.main();
   });
 }