shelf_route and shelf_web_socket

[Oliver]

I'm trying to use shelf_route in combination with shelf_web_socket to have both multiple WebSocket endpoints and a REST api on the same webserver.

My current code looks like this (stripped down):

import 'package:shelf/shelf.dart' as shelf;
import 'package:shelf/shelf_io.dart' as io;
import 'package:shelf_route/shelf_route.dart' as route;
import 'package:shelf_web_socket/shelf_web_socket.dart';


void main(List<String> arguments) {

  r(shelf.Request re) {
    return new shelf.Response.ok('test');
  }

  var router = (route.router()
      ..add( '/rest', ['GET'], r)
      ..add( '/ws', ['GET'], webSocketHandler((ws) {
        print('Connected!');
      })));

  var handler = const shelf.Pipeline()
      .addMiddleware(shelf.logRequests())
      .addHandler(router.handler);

  io.serve(handler, '127.0.0.1', 30091).then((server) {
    print('Serving at http://${server.address.host}:${server.port}');
  });
}

The code works fine for the REST part. But if I try to connect to the websocket server, I get the following exception:

Error thrown by handler.
Illegal argument(s): webSocketHandler may only be used with a server that supports request hijacking.
package:shelf_web_socket/src/web_socket_handler.dart 53:7  handle
package:shelf_route/shelf_route.dart 294:20                _Route.handle
package:shelf_route/shelf_route.dart 224:24                _handleRequest
dart:isolate                                               _RawReceivePortImpl._handleMessage

At the beginning of a request, hijacking seems to be supported. But the problem comes in combination with the route package.

I tracked the problem down to the Request.change method in the shelf package. It copies a request, but doesn't copy the hijacking handler. 

I wonder if this behavior is intentional and I'm using the packages in the wrong way, or if it was missed during writing the package?

[Oliver]

I created a simple fix for the problem here.

[Natalie Weizenbaum]

It looks like the shelf_route package isn't properly forwarding the request objects so that they preserve all of their metadata, in particular the onHijack field. It should be using Request.change to create new requests based on old ones, but it may not be.

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[Anders Holmgren]

I recommend you file a bug on shelf. It seems pretty clear cut to me unless I'm missing something too.

[Natalie Weizenbaum]

I believe this is a bug in shelf_route, not shelf itself.

On Mon, Sep 22, 2014 at 1:17 PM, Anders Holmgren <andersm...@gmail.com> wrote:

I recommend you file a bug on shelf. It seems pretty clear cut to me unless I'm missing something too.

[Oliver]

No, shelf_route uses Request.change. But the problem is that the Request.change method from shelf is not forwarding the onHijack callback at all. See https://github.com/dart-lang/bleeding_edge/blob/master/dart/pkg/shelf/lib/src/request.dart#L197

I would expect that it looks somehow like this: https://github.com/Fox32/shelf/blob/master/lib/src/request.dart#L119

[Natalie Weizenbaum]

Ah, you're right. Can you file an issue against shelf for that, or better yet, submit a patch?

[Oliver]

I created issue 21043 for that.

I would submit a patch if that package would be hosted on GitHub. Setting it up for Google Code is to much work =(