✨ Add graphql support and add first graphql endpoint

lib/src/common/github.dart

@@ -6,6 +6,8 @@ import 'package:http/http.dart' as http;
 import 'package:http_parser/http_parser.dart' as http_parser;
 import 'package:meta/meta.dart';
 
+import 'graphql_service.dart';
+
 ///  The Main GitHub Client
 ///
 ///  ## Example
@@ -63,6 +65,7 @@ class GitHub {
   UrlShortenerService? _urlShortener;
   UsersService? _users;
   ChecksService? _checks;
+  GraphQLService? _graphql;
 
   /// The maximum number of requests that the consumer is permitted to make per
   /// hour.
@@ -143,6 +146,9 @@ class GitHub {
   /// See https://developer.github.com/v3/checks/
   ChecksService get checks => _checks ??= ChecksService(this);
 
+  /// Service for GraphQL related methods of the GitHub API.
+  GraphQLService get graphql => _graphql ??= GraphQLService(this);
+
   /// Handles Get Requests that respond with JSON
   /// [path] can either be a path like '/repos' or a full url.
   /// [statusCode] is the expected status code. If it is null, it is ignored.

lib/src/common/graphql_service.dart

@@ -0,0 +1,47 @@
+import 'dart:async';
+
+import 'package:graphql/client.dart';
+
+import 'github.dart';
+
+/// Service for handling GraphQL requests.
+class GraphQLService {
+  final GitHub github;
+  late final GraphQLClient _client;
+
+  GraphQLService(this.github) {
+    final httpLink = HttpLink('https://api.github.com/graphql');
+
+    final authLink = AuthLink(
+      getToken: () async => 'Bearer ${github.auth.token}',
+    );
+
+    final link = authLink.concat(httpLink);
+
+    _client = GraphQLClient(cache: GraphQLCache(), link: link);
+  }
+
+  /// Performs a GraphQL query.
+  Future<QueryResult> query(
+    String query, {
+    Map<String, dynamic>? variables,
+  }) async {
+    final options = QueryOptions(
+      document: gql(query),
+      variables: variables ?? const <String, dynamic>{},
+    );
+    return _client.query(options);
+  }
+
+  /// Performs a GraphQL mutation.
+  Future<QueryResult> mutate(
+    String mutation, {
+    Map<String, dynamic>? variables,
+  }) async {
+    final options = MutationOptions(
+      document: gql(mutation),
+      variables: variables ?? const <String, dynamic>{},
+    );
+    return _client.mutate(options);
+  }
+}

lib/src/services/issues_service.dart

@@ -566,4 +566,31 @@ class IssuesService extends Service {
       statusCode: 204,
     );
   }
+
+  /// Deletes an issue.
+  ///
+  /// This uses the GraphQL API, since issue deletion is not available in the REST API.
+  ///
+  /// API docs: https://docs.github.com/en/graphql/reference/mutations#deleteissue
+  Future<void> deleteIssue(RepositorySlug slug, int issueNumber) async {
+    final issue = await get(slug, issueNumber);
+    final issueId = issue.nodeId;
+
+    const mutation = r'''
+      mutation DeleteIssue($issueId: ID!) {
+        deleteIssue(input: {issueId: $issueId}) {
+          clientMutationId
+        }
+      }
+    ''';
+
+    final result = await github.graphql.mutate(
+      mutation,
+      variables: {'issueId': issueId},
+    );
+
+    if (result.hasException) {
+      throw result.exception!;
+    }
+  }
 }

pubspec.yaml

@@ -10,6 +10,7 @@ environment:
 dependencies:
   flutter:
     sdk: flutter
+  graphql: ^5.2.1
   http: ^1.3.0
   http_parser:
   json_annotation: ^4.9.0

test/unit/issues_test.dart

@@ -1,6 +1,9 @@
 import 'dart:convert';
 
-import 'package:github_flutter/src/models/issues.dart';
+import 'package:github_flutter/src/common.dart';
+import 'package:github_flutter/src/common/graphql_service.dart';
+import 'package:graphql/client.dart';
+import 'package:http/http.dart' as http;
 import 'package:test/test.dart';
 
 const String testIssueCommentJson = '''
@@ -50,6 +53,76 @@ const String testIssueCommentJson = '''
   }
 ''';
 
+typedef GetJSONCallback =
+    Future<T> Function<S, T>(
+      String path, {
+      int? statusCode,
+      void Function(http.Response)? fail,
+      Map<String, String>? headers,
+      Map<String, String>? params,
+      JSONConverter<S, T>? convert,
+      String? preview,
+    });
+
+// A mock implementation of GitHub that uses noSuchMethod to avoid implementing
+// all methods of the GitHub class.
+class MockGitHub implements GitHub {
+  @override
+  late final GraphQLService graphql;
+
+  late GetJSONCallback onGetJSON;
+
+  MockGitHub(this.graphql);
+
+  @override
+  Future<T> getJSON<S, T>(
+    String path, {
+    int? statusCode,
+    void Function(http.Response)? fail,
+    Map<String, String>? headers,
+    Map<String, String>? params,
+    JSONConverter<S, T>? convert,
+    String? preview,
+  }) {
+    return onGetJSON<S, T>(
+      path,
+      statusCode: statusCode,
+      fail: fail,
+      headers: headers,
+      params: params,
+      convert: convert,
+      preview: preview,
+    );
+  }
+
+  @override
+  dynamic noSuchMethod(Invocation invocation) {
+    // This is needed to avoid implementing all methods of the GitHub class.
+    // We only care about getJSON and graphql.
+  }
+}
+
+// A manual mock for GraphQLService to avoid mockito issues.
+class MockGraphQLService implements GraphQLService {
+  // Callback to be set by the test.
+  late Future<QueryResult> Function(String, Map<String, dynamic>?) onMutate;
+
+  @override
+  Future<QueryResult> mutate(
+    String mutation, {
+    Map<String, dynamic>? variables,
+  }) {
+    return onMutate(mutation, variables);
+  }
+
+  // Unimplemented members
+  @override
+  GitHub get github => throw UnimplementedError();
+  @override
+  Future<QueryResult> query(String query, {Map<String, dynamic>? variables}) =>
+      throw UnimplementedError();
+}
+
 void main() {
   group('Issue Comments', () {
     test('IssueComment from Json', () {
@@ -61,4 +134,152 @@ void main() {
       expect('CaseyHillers', issueComment.user!.login);
     });
   });
+
+  group('IssuesService', () {
+    late IssuesService issuesService;
+    late MockGitHub mockGitHub;
+    late MockGraphQLService mockGraphQLService;
+
+    setUp(() {
+      mockGraphQLService = MockGraphQLService();
+      mockGitHub = MockGitHub(mockGraphQLService);
+      issuesService = IssuesService(mockGitHub);
+    });
+
+    test('deleteIssue success', () async {
+      // Arrange
+      String? capturedMutation;
+      Map<String, dynamic>? capturedVariables;
+      final slug = RepositorySlug('owner', 'repo');
+      const issueNumber = 1;
+      const issueNodeId = 'issue-node-id-456';
+
+      mockGitHub.onGetJSON = <S, T>(
+        String path, {
+        int? statusCode,
+        void Function(http.Response)? fail,
+        Map<String, String>? headers,
+        Map<String, String>? params,
+        JSONConverter<S, T>? convert,
+        String? preview,
+      }) async {
+        if (path == '/repos/owner/repo/issues/1') {
+          final issueJson = {
+            'id': 1,
+            'node_id': issueNodeId,
+            'number': issueNumber,
+            'state': 'open',
+            'title': 'Test Issue',
+            'url': 'https://api.github.com/repos/owner/repo/issues/1',
+            'html_url': 'https://github.com/owner/repo/issues/1',
+            'body': 'Test Body',
+          };
+          final issue = convert!(issueJson as S);
+          return issue;
+        }
+        throw Exception('Unexpected path: $path');
+      };
+
+      mockGraphQLService.onMutate = (mutation, variables) {
+        capturedMutation = mutation;
+        capturedVariables = variables;
+        return Future.value(
+          QueryResult(
+            options: QueryOptions(
+              document: gql(''),
+            ), // ignore: deprecated_member_use
+            source: QueryResultSource.network,
+            data: const {
+              'deleteIssue': {'clientMutationId': '1234'},
+            },
+          ),
+        );
+      };
+
+      // Act
+      await issuesService.deleteIssue(slug, issueNumber);
+
+      // Assert
+      expect(capturedMutation, contains('mutation DeleteIssue'));
+      expect(capturedVariables, {'issueId': issueNodeId});
+    });
+
+    test('deleteIssue failure on get', () async {
+      // Arrange
+      final slug = RepositorySlug('owner', 'repo');
+      const issueNumber = 1;
+
+      mockGitHub.onGetJSON = <S, T>(
+        String path, {
+        int? statusCode,
+        void Function(http.Response)? fail,
+        Map<String, String>? headers,
+        Map<String, String>? params,
+        JSONConverter<S, T>? convert,
+        String? preview,
+      }) async {
+        throw Exception('Failed to get issue');
+      };
+
+      // Act & Assert
+      expect(
+        () => issuesService.deleteIssue(slug, issueNumber),
+        throwsA(isA<Exception>()),
+      );
+    });
+
+    test('deleteIssue failure on mutate', () async {
+      // Arrange
+      final slug = RepositorySlug('owner', 'repo');
+      const issueNumber = 1;
+      const issueNodeId = 'issue-node-id-456';
+
+      mockGitHub.onGetJSON = <S, T>(
+        String path, {
+        int? statusCode,
+        void Function(http.Response)? fail,
+        Map<String, String>? headers,
+        Map<String, String>? params,
+        JSONConverter<S, T>? convert,
+        String? preview,
+      }) async {
+        if (path == '/repos/owner/repo/issues/1') {
+          final issueJson = {
+            'id': 1,
+            'node_id': issueNodeId,
+            'number': issueNumber,
+            'state': 'open',
+            'title': 'Test Issue',
+            'url': 'https://api.github.com/repos/owner/repo/issues/1',
+            'html_url': 'https://github.com/owner/repo/issues/1',
+            'body': 'Test Body',
+          };
+          final issue = convert!(issueJson as S);
+          return issue;
+        }
+        throw Exception('Unexpected path: $path');
+      };
+
+      final exception = OperationException(
+        graphqlErrors: [const GraphQLError(message: 'Failed to delete')],
+      );
+      mockGraphQLService.onMutate = (mutation, variables) {
+        return Future.value(
+          QueryResult(
+            options: QueryOptions(
+              document: gql(''),
+            ), // ignore: deprecated_member_use
+            source: QueryResultSource.network,
+            exception: exception,
+          ),
+        );
+      };
+
+      // Act & Assert
+      expect(
+        () => issuesService.deleteIssue(slug, issueNumber),
+        throwsA(isA<OperationException>()),
+      );
+    });
+  });
 }