Using .NET Core 2.2 and Angular 8 with package "@aspnet/signalr": "^1.1.4"
.
I have set up a hub in .NET Core 2.2 which works fine with another Angular project using the same package.
Startup.cs
:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.AspNetCore.Mvc;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Hosting;
using Microsoft.Extensions.Logging;
using SignalrChat.Services;
namespace SignalrChat
{
public class Startup
{
public Startup(IConfiguration configuration)
{
Configuration = configuration;
}
public IConfiguration Configuration { get; }
// This method gets called by the runtime. Use this method to add services to the container.
public void ConfigureServices(IServiceCollection services)
{
services.AddCors(o => o.AddPolicy("CorsPolicy", builder =>
{
builder
.AllowAnyHeader()
.AllowAnyMethod()
.SetIsOriginAllowed(_ => true)
.AllowCredentials();
}));
services.AddSignalR();
services.AddSingleton<IChatRoomService, InMemoryChatRoomService>();
services.AddControllers();
}
// This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
{
if (env.IsDevelopment())
{
app.UseDeveloperExceptionPage();
}
app.UseRouting();
app.UseAuthorization();
app.UseCors("CorsPolicy");
app.UseEndpoints(endpoints =>
{
endpoints.MapControllers();
endpoints.MapHub<ChatHub>("/chat");
});
}
}
}
Hub:
using Microsoft.AspNetCore.SignalR;
using SignalrChat.Models;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
namespace SignalrChat
{
public class ChatHub : Hub
{}
}
Angular:
import * as signalR from "@aspnet/signalr";
import {
Component, Inject, OnInit
} from '@angular/core';
import { DeviceDetectorService } from 'ngx-device-detector';
import { DOCUMENT } from '@angular/common';
import { Router } from '@angular/router';
@Component({
selector: 'app-root',
templateUrl: './app.component.html',
styleUrls: ['./app.component.css']
})
export class AppComponent implements OnInit {
ngOnInit(): void {
this.hub = new signalR.HubConnectionBuilder()
.configureLogging(signalR.LogLevel. Trace)
.withUrl('http://localhost:56328/chat')
.build();
this.hub.serverTimeoutInMilliseconds = 100000;
this.hub.keepAliveIntervalInMilliseconds = 100000;
this.hub
.start()
.then(() => {
console.log('Connection started!');
console.log('Getting all rooms');
})
.catch(err => {
console.log(err);
console.log(this.hub);
});
}
}
Here is the log for hub.start()
from Angular project that works fine:
[2019-12-31T11:43:30.214Z] Debug: Starting HubConnection.
Utils.js:213 [2019-12-31T11:43:30.215Z] Debug: Starting connection with transfer format 'Text'.
Utils.js:213 [2019-12-31T11:43:30.220Z] Debug: Sending negotiation request: http://localhost:56328/chat/negotiate.
Utils.js:213 [2019-12-31T11:43:31.382Z] Debug: Selecting transport 'WebSockets'.
client:52 [WDS] Live Reloading enabled.
Utils.js:209 [2019-12-31T11:43:32.001Z] Information: WebSocket connected to ws://localhost:56328/chat?id=NafCuVY_brPNmqQlN2EvXw.
Utils.js:213 [2019-12-31T11:43:32.003Z] Debug: Sending handshake request.
Utils.js:209 [2019-12-31T11:43:32.006Z] Information: Using HubProtocol 'json'.
Utils.js:213 [2019-12-31T11:43:32.053Z] Debug: Server handshake complete.
But for the other angular project with the exact same code and package to the same hub, it cannot proceed. Here is the log:
[2019-12-31T11:41:35.294Z] Debug: Starting HubConnection.
Utils.js:213 [2019-12-31T11:41:35.639Z] Debug: Starting connection with transfer format 'Text'.
Utils.js:213 [2019-12-31T11:41:35.644Z] Debug: Sending negotiation request: http://localhost:56328/chat/negotiate.
core.js:16829 Angular is running in the development mode. Call enableProdMode() to enable the production mode.
Utils.js:213 [2019-12-31T11:41:36.574Z] Debug: Selecting transport 'WebSockets'.
WebSocket connection to 'ws://localhost:4200/sockjs-node/694/1skccdzm/websocket' failed: WebSocket is closed before the connection is established.
[2019-12-31T11:41:38.814Z] Information: WebSocket connected to ws://localhost:56328/chat?id=qO3s36husX9-boU1SwyaBg.
Utils.js:213 [2019-12-31T11:41:38.820Z] Debug: Sending handshake request.
app.component.ts:34 WebSocket is not in the OPEN state
I tried to change all the packages of the "not-wroking angular" to the same as the "working-angular", the problem still remains.
UPDATE
I found out that changing http transport mode of signalR.HubConnectionBuilder() will get it worked as below:
var options = {
transport: signalR.HttpTransportType.ServerSentEvents ,
logging: signalR.LogLevel.Trace,
};
this.hub = new signalR.HubConnectionBuilder()
//.withUrl('http://localhost:56328/chat' , options)
.withUrl('http://localhost:49941/chat', options)
.build();
ServerSentEvent is successful, yet the websocket and longpolling modes are not.
Thanks to @Fei Han for mentioning this useful solution: it worked when i changed my code to this:
Object.defineProperty(WebSocket, 'OPEN', { value: 1, });
this.hub
.start()
.then(() => {
console.log('Connection started!');
})
.catch(err => {
console.log(err);
});