部署到Prod时，WebSockets不能与SignalR Core一起使用 [英] WebSockets don't work with SignalR Core when deployed to Prod

问题描述

在IIS 8.5后面运行的ASP.NET Core 2.1

ASP.NET Core 2.1 running behind IIS 8.5

SignalR在连接时似乎没有协商子协议，因此无法完成连接.从客户端发送到服务器的消息永远不会收到.

SignalR doesn't seem to negotiate a Sub-Protocol when connecting and fails to complete the connection. Messages sent from the client to the server are never received.

我无法将站点配置为直接从Kestrel提供服务，因为这是共享服务器. 将传输方式更改为长时间轮询. 我尝试禁用HTTPS/HSTS重定向.

I can't configure the site to serve from Kestrel directly as this is a shared server. Changing the transport to long-polling works. I have tried disabling HTTPS/HSTS redirection.

随附来自客户端和服务器的日志:

Attached are the logs from the client and the server:

客户日志:

Information: Normalizing 'hubs/screen' to 'https://<url>/hubs/screen'.
Utils.ts:173 Information: WebSocket connected to ws://<url>/hubs/screen?id=
...
Error: Connection disconnected with error 'Error: Server timeout elapsed without receiving a message from the server.'.<id>

服务器日志:

dbug: Microsoft.AspNetCore.Http.Connections.Internal.HttpConnectionManager[1]
      New connection <id> created.
dbug: Microsoft.AspNetCore.Http.Connections.Internal.HttpConnectionDispatcher[10]
      Sending negotiation response.
dbug: Microsoft.AspNetCore.Http.Connections.Internal.HttpConnectionDispatcher[4]
      Establishing new connection.
dbug: Microsoft.AspNetCore.SignalR.HubConnectionHandler[5]
      OnConnectedAsync started.
dbug: Microsoft.AspNetCore.Http.Connections.Internal.Transports.WebSocketsTransport[1]
      Socket opened using Sub-Protocol: '(null)'.
dbug: Microsoft.AspNetCore.Http.Connections.Internal.Transports.WebSocketsTransport[14]
      Socket connection closed prematurely.
System.Net.WebSockets.WebSocketException (0x80004005): The remote party closed the WebSocket connection without completing the close handshake. ---> System.Net.WebSockets.WebSocketException (0x80004005): The remote party closed the WebSocket connection without completing the close handshake.
   at System.Net.WebSockets.ManagedWebSocket.ThrowIfEOFUnexpected(Boolean throwOnPrematureClosure)
   at System.Net.WebSockets.ManagedWebSocket.EnsureBufferContainsAsync(Int32 minimumRequiredBytes, Boolean throwOnPrematureClosure)
   at System.Net.WebSockets.ManagedWebSocket.ReceiveAsyncPrivate[TWebSocketReceiveResultGetter,TWebSocketReceiveResult](Memory`1 payloadBuffer, CancellationToken cancellationToken, TWebSocketReceiveResultGetter resultGetter)
   at System.Net.WebSockets.ManagedWebSocket.ReceiveAsyncPrivate[TWebSocketReceiveResultGetter,TWebSocketReceiveResult](Memory`1 payloadBuffer, CancellationToken cancellationToken, TWebSocketReceiveResultGetter resultGetter)
   at System.Net.WebSockets.WebSocket.ReceiveAsync(Memory`1 buffer, CancellationToken cancellationToken)
   at Microsoft.AspNetCore.Http.Connections.Internal.Transports.WebSocketsTransport.StartReceiving(WebSocket socket)
fail: Microsoft.AspNetCore.SignalR.HubConnectionContext[5]
      Failed connection handshake.
dbug: Microsoft.AspNetCore.Http.Connections.Internal.Transports.WebSocketsTransport[4]
      Waiting for the application to finish sending data.
dbug: Microsoft.AspNetCore.Http.Connections.Internal.Transports.WebSocketsTransport[2]
      Socket closed.

推荐答案

我发现了问题！

我们有一个自定义IIS模块，该模块将服务器名称+请求计时作为HTTP标头注入，这导致SignalR失败. (该模块可能只是盲目地注入其标头，而不考虑Websockets)

We had a custom IIS module that injected server name + request timing as an HTTP header and this was causing SignalR to fail. (The module was probably just blindly injecting its header, without respect to Websockets)

这篇关于部署到Prod时，WebSockets不能与SignalR Core一起使用的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！