feat(graphql): add possibility to update the client components

This is a very opinionated API, but it is required because it hide the complexity of the client under the hood.

The user should never know the how we use the component and how the client it built.

The user need to know that we are like Harry Potter and the stuff happens like magic.

Signed-off-by: Vincenzo Palazzo <[email protected]>

Author: vincenzopalazzo

packages/graphql/lib/src/graphql_client.dart

@@ -44,6 +44,19 @@ class GraphQLClient implements GraphQLDataProxy {
 
   late final QueryManager queryManager;
 
+  /// Create a copy of the client with the provided information.
+  GraphQLClient copyWith(
+      {Link? link,
+      GraphQLCache? cache,
+      DefaultPolicies? defaultPolicies,
+      bool? alwaysRebroadcast}) {
+    return GraphQLClient(
+        link: link ?? this.link,
+        cache: cache ?? this.cache,
+        defaultPolicies: defaultPolicies ?? this.defaultPolicies,
+        alwaysRebroadcast: alwaysRebroadcast ?? queryManager.alwaysRebroadcast);
+  }
+
   /// This registers a query in the [QueryManager] and returns an [ObservableQuery]
   /// based on the provided [WatchQueryOptions].
   ///

packages/graphql/test/graphql_client_test.dart

@@ -154,6 +154,7 @@ void main() {
           equals('bar'),
         );
       });
+
       test('successful response with parser', () async {
         final ResultParserFn<List<String>> parserFn = (data) {
           return (data['viewer']['repositories']['nodes'] as List)
@@ -1048,4 +1049,76 @@ void main() {
       expect(client.readQuery(queryRequest), equals(updatedQueryData));
     });
   });
+
+  group("Client management", () {
+    setUp(() {
+      link = MockLink();
+
+      client = GraphQLClient(
+        cache: getTestCache(),
+        link: link,
+      );
+    });
+
+    test('successful response with update link', () async {
+      final _options = QueryOptions(
+        document: parseString(readRepositories),
+        variables: <String, dynamic>{
+          'nRepositories': 42,
+        },
+      );
+      final repoData = readRepositoryData(withTypenames: true);
+
+      when(
+        link.request(any),
+      ).thenAnswer(
+        (_) => Stream.fromIterable([
+          Response(
+            data: repoData,
+            context: Context().withEntry(
+              HttpLinkResponseContext(
+                statusCode: 200,
+                headers: {'foo': 'bar'},
+              ),
+            ),
+            response: {},
+          ),
+        ]),
+      );
+      // FIXME(vincenzopalazzo): adding a new mock link, maybe to print some addition
+      // information.
+      link = MockLink();
+      when(
+        link.request(any),
+      ).thenAnswer(
+        (_) => Stream.fromIterable([
+          Response(
+            data: repoData,
+            context: Context().withEntry(
+              HttpLinkResponseContext(
+                statusCode: 200,
+                headers: {'foo': 'bar'},
+              ),
+            ),
+            response: {},
+          ),
+        ]),
+      );
+
+      client = client.copyWith(link: link);
+      final QueryResult r = await client.query(_options);
+
+      expect(r.exception, isNull);
+      expect(r.data, equals(repoData));
+
+      expect(
+        r.context.entry<HttpLinkResponseContext>()!.statusCode,
+        equals(200),
+      );
+      expect(
+        r.context.entry<HttpLinkResponseContext>()!.headers['foo'],
+        equals('bar'),
+      );
+    });
+  });
 }

packages/graphql_flutter/test/widgets/subscription_test.dart

@@ -114,4 +114,4 @@ void main() {
       verifyNoMoreInteractions(mockHttpClient);
     });
   });
-}
+}