Need more headers in AuthLink

[endigo]

Our API service uses access-token and refresh token.

Here just one header: 'Authorization'
https://github.com/zino-app/graphql-flutter/blob/next/lib/src/link/auth/link_auth.dart#L21

We need 3 custom named headers.
for example:

HttpLink(uri: global.graphqlEndpoint, headers: {
  'x-token': state.user.accessToken,
  'x-refresh-token': state.user.refreshToken,
  'accept-language': locale.toString()
}),

Thanks.

[HofmannZ]

You can write your own Link:

typedef GetHeaders = Future<Map<String, String>> Function();

class CustomAuthLink extends Link {
  CustomAuthLink({
    this.getHeaders,
  }) : super(
          request: (Operation operation, [NextLink forward]) {
            StreamController<FetchResult> controller;

            Future<void> onListen() async {
              try {
                final Map<String, String> headers = await getHeaders();

                operation.setContext(<String, Map<String, String>>{
                  'headers': headers
                });
              } catch (error) {
                controller.addError(error);
              }

              await controller.addStream(forward(operation));
              await controller.close();
            }

            controller = StreamController<FetchResult>(onListen: onListen);

            return controller.stream;
          },
        );

  GetHeaders getHeaders;
}

And then you can implement it just as you would with the AuthLink.

Hope that helps!

[HofmannZ]

Closing, seems revolved.

[5hanth]

@HofmannZ need to reopen this as the above CustomAuthLink's parameter signatures fails for 4.0.0

[HofmannZ]

@5hanth we moved to a new link system, see https://github.com/zino-app/graphql-flutter/blob/beta/changelog-v3-v4.md#we-now-use-the-gql_link-system

[bgparkerdev]

If people are having a hard time finding an example. https://github.com/gql-dart/gql/blob/master/links/gql_link/example/gql_link_example.dart

[MSRPRO]

You can create your own link (updated answer 2021) :

import 'dart:async';

import 'package:graphql/client.dart';

typedef _RequestTransformer = FutureOr<Request> Function(Request request);

class CustomAuthLink extends _AsyncReqTransformLink {
  CustomAuthLink({
    required this.getHeaders,
  }) : super(requestTransformer: transform(getHeaders));

  final FutureOr<Map<String, String>>? Function() getHeaders;

  static _RequestTransformer transform(
    FutureOr<Map<String, String>>? Function() getHeaders,
  ) =>
      (Request request) async {
        final Map<String, String>? headers = await getHeaders();
        return request.updateContextEntry<HttpLinkHeaders>(
          (_headers) => HttpLinkHeaders(
            headers: headers!,
          ),
        );
      };
}

class _AsyncReqTransformLink extends Link {
  final _RequestTransformer requestTransformer;

  _AsyncReqTransformLink({
    required this.requestTransformer,
  });

  @override
  Stream<Response> request(
    Request request, [
    NextLink? forward,
  ]) async* {
    final req = await requestTransformer(request);

    yield* forward!(req);
  }
}