Node.js服务端运行SignalR客户端遇连接拒绝错误，求解决方法

问题描述 #

尝试在Node.js环境运行SignalR客户端时出现连接拒绝错误，客户端代码及报错信息如下：

客户端代码（Chat.js） #

const signalR = require("@microsoft/signalr");

const connection = new signalR.HubConnectionBuilder()
  .withUrl("http://127.0.0.1:7265/chathub")
  .configureLogging(signalR.LogLevel.Information)
  .build();

const start = async () => {
  try {
    await connection.start();
    console.log("Connected to signal r hub");
  } catch (error) {
    console.log(error);
  }
};
// starting the app
const startApp = async () => {
  await start(); // connection will stablised
};

startApp();

报错信息 #

[2023-04-08T07:27:03.490Z] Error: Failed to complete negotiation with the server: FetchError: request to http://127.0.0.1:7265/chathub/negotiate?negotiateVersion=1 failed, reason: connect ECONNREFUSED 127.0.0.1:7265
[2023-04-08T07:27:03.490Z] Error: Failed to start the connection: Error: Failed to complete negotiation with the server: FetchError: request to http://127.0.0.1:7265/chathub/negotiate?negotiateVersion=1 failed, reason: connect ECONNREFUSED 127.0.0.1:7265
FailedToNegotiateWithServerError: Failed to complete negotiation with the server: FetchError: request to http://127.0.0.1:7265/chathub/negotiate?negotiateVersion=1 failed, reason: connect ECONNREFUSED 127.0.0.1:7265
    at HttpConnection._getNegotiationResponse (/Users/user/Desktop/WebChat-Client-master/node_modules/@microsoft/signalr/dist/cjs/HttpConnection.js:256:35)
    at processTicksAndRejections (node:internal/process/task_queues:96:5)
    at async HttpConnection._startInternal (/Users/user/Desktop/WebChat-Client-master/node_modules/@microsoft/signalr/dist/cjs/HttpConnection.js:172:41)
    at async HttpConnection.start (/Users/user/Desktop/WebChat-Client-master/node_modules/@microsoft/signalr/dist/cjs/HttpConnection.js:75:9)
    at async HubConnection._startInternal (/Users/user/Desktop/WebChat-Client-master/node_modules/@microsoft/signalr/dist/cjs/HubConnection.js:132:9)
    at async HubConnection._startWithStateTransitions (/Users/user/Desktop/WebChat-Client-master/node_modules/@microsoft/signalr/dist/cjs/HubConnection.js:109:13)
    at async start (/Users/user/Desktop/WebChat-Client-master/chat.js:10:5)
    at async startApp (/Users/user/Desktop/WebChat-Client-master/chat.js:18:3) {
  errorType: 'FailedToNegotiateWithServerError'
}

解决步骤 #

报错核心是connect ECONNREFUSED 127.0.0.1:7265，说明客户端无法连接到指定地址的SignalR服务端，按以下步骤排查：

• 确认服务端是否运行
  检查7265端口是否被占用：

  • Mac/Linux执行：lsof -i :7265
  • Windows执行：netstat -ano | findstr :7265
    如果无输出，说明SignalR服务端未启动，先启动服务端再试。

• 验证服务端Hub路由配置
  手动在浏览器访问http://127.0.0.1:7265/chathub/negotiate，如果返回JSON格式的协商数据，说明路由配置正常；如果404或无法访问，检查服务端的Hub注册代码（比如ASP.NET Core中需确保app.MapHub<ChatHub>("/chathub");已正确添加）。

• 核对连接地址正确性

  • 确认服务端实际监听的端口和协议（比如服务端用HTTPS的话，客户端地址要改成https://127.0.0.1:7265/chathub）
  • 若服务端和客户端不在同一机器，替换127.0.0.1为服务端的实际IP或域名。

• 处理跨域问题（若存在跨域场景）
  如果客户端Node.js服务和SignalR服务端不在同一域名/端口，需在服务端配置CORS，允许客户端的请求来源。以ASP.NET Core为例，需添加：

  builder.Services.AddCors(options =>
  {
      options.AddPolicy("AllowNodeClient", policy =>
      {
          policy.WithOrigins("http://你的客户端地址")
                .AllowAnyHeader()
                .AllowAnyMethod()
                .AllowCredentials();
      });
  });
  
  app.UseCors("AllowNodeClient");
  

• 添加重连逻辑（可选优化）
  为客户端添加断开自动重连逻辑，提升稳定性：

  connection.onclose(async () => {
    console.log("连接断开，5秒后尝试重连...");
    setTimeout(start, 5000);
  });
  

内容的提问来源于stack exchange，提问作者jalil_cse