如何使用 shelf_web_socket 监听同一端口上的 http 和 ws 请求

Question

https://pub.dartlang.org/packages/shelf_web_socket显示了此示例

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

void main() {
  var handler = webSocketHandler((webSocket) {
    webSocket.listen((message) {
      webSocket.add("echo $message");
    });
  });

  shelf_io.serve(handler, 'localhost', 8080).then((server) {
    print('Serving at ws://${server.address.host}:${server.port}');
  });
}

我想知道如何将其与我的 HTTP 服务器初始化结合起来

import 'package:shelf/shelf.dart' as shelf;
import 'package:shelf/shelf_io.dart' as sIo;
import 'package:shelf_auth/shelf_auth.dart' as sAuth;
import 'package:shelf_auth/src/authentication.dart' as sAuth2;
import 'package:option/option.dart';
import 'package:shelf_web_socket/shelf_web_socket.dart' as sWs;

...

var authMiddleware = sAuth.authenticate(
    [new MyAuthenticator()],
    sessionHandler: new sAuth.JwtSessionHandler('bla', 'blub', new UserLookup()),
    allowHttp: true,
    allowAnonymousAccess: false);

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

// var wsHandler = sWs.webSocketHandler(_handleWebSocketConnect);

sIo.serve(handler, '0.0.0.0', servePort).then((server) {
  _log.finest('Serving at http://${server.address.host}:${server.port}');
});

需要做什么才能wsHandler调用 WebSocket 连接并handler继续处理 HTTP 请求（如果可能在同一端口上），并且如果可能的话使用配置的身份验证和会话管理。

我在不同的端口上尝试了它，但使用了身份验证/会话中间件（不知道这是否应该一起使用）

   var authMiddleware = sAuth.authenticate(
        [new MyAuthenticator()],
        sessionHandler: new sAuth.JwtSessionHandler('bla', 'blub', new UserLookup()),
        allowHttp: true,
        allowAnonymousAccess: false);

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

    sIo.serve(handler, '0.0.0.0', servePort).then((server) {
      _log.finest('Serving at http://${server.address.host}:${server.port}');
    });


    var wsHandler = const shelf.Pipeline()
      .addMiddleware(shelf.logRequests())
      .addMiddleware(authMiddleware)
      .addHandler(sWs.webSocketHandler(_handleWebSocketConnect));

    sIo.serve(wsHandler, '0.0.0.0', servePort + 1).then((server) {
      _log.finest('Serving at ws://${server.address.host}:${server.port}');
    });

并得到了

Illegal argument(s): webSocketHandler may only be used with a server that supports request hijacking.

Answer 1

目前，您的根处理程序是 http 处理程序。您需要设置一个处理程序，有条件地将请求发送到 ws 处理程序或您的 http 请求的另一个处理程序。例如

/ws -> 你的 ws 处理程序

/rest -> 你的其他处理程序

最简单的方法是使用像shelf_route这样的路由器。

然而，最近有人尝试了这一点，并遇到了架子上的错误，导致该功能停止工作。正如您在下面指出的那样，这是固定的但未合并。

问题解决后，您应该能够执行以下操作

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' as sWs;
import 'package:shelf_auth/shelf_auth.dart' as sAuth;
import 'dart:async';
import 'package:option/option.dart';
import 'package:shelf_exception_response/exception_response.dart';

void main(List<String> arguments) {

  var authMiddleware = sAuth.authenticate(
        [new MyAuthenticator()],
        sessionHandler: new sAuth.JwtSessionHandler('bla', 'blub', new UserLookup()),
        allowHttp: true,
        allowAnonymousAccess: false);


  var router = (route.router()
      ..get('/rest', _handleHttpRequest)
      ..get('/ws', sWs.webSocketHandler(_handleWebSocketConnect)));

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

  route.printRoutes(router);

  io.serve(handler, '127.0.0.1', 8080).then((server) {
    print('Serving at http://${server.address.host}:${server.port}');
  });
}

在问题解决之前，您可以将 router.handler 替换为

var hackyRouterHandler = (shelf.Request request) {
  var path = request.url.path;
  if (path.startsWith('/rest')) {
    return _handleHttpRequest(request);
  }
  else if (path.startsWith('/ws')) {
    return sWs.webSocketHandler(_handleWebSocketConnect)(request);
  }
  else {
    throw new NotFoundException();
  }
};