DEV Community

Cover image for nderstanding Reverse Proxy with .NET & SignalR (With Source Code + ZIP)
Morteza Jangjoo
Morteza Jangjoo

Posted on

nderstanding Reverse Proxy with .NET & SignalR (With Source Code + ZIP)

#dotnet #csharp #proxy #reverse

Reverse Proxy plays a critical role in modern web architecture — especially when building real-time applications using SignalR.
In this guide, we’ll break down what a reverse proxy is, why you need it, and how to use it with .NET + YARP + SignalR.

Fully working example
Client → Proxy → SignalR architecture
ZIP source code included

What is a Reverse Proxy?

A reverse proxy is a server that sits in front of your backend services and forwards client requests to them.

Key benefits:

  • Load balancing
  • SSL termination
  • Central authentication & security
  • WebSockets support (important for SignalR!)
  • Routing multiple services under one public endpoint

📡 Why use Reverse Proxy with SignalR?

When building real-time systems (trading apps, dashboards, chat, IoT streaming) you may need:

Challenge Reverse Proxy Solution
Clients change endpoints? One static external URL ✅
SSL offload? Proxy handles certs ✅
Distribute load? Proxy balances hubs ✅
Run multiple backend instances? Cluster routing ✅

Architecture 

Client → Reverse Proxy (YARP) → SignalR Server
Enter fullscreen mode Exit fullscreen mode

Full Example

We will run:

App Port
SignalR Server 5000
YARP Reverse Proxy 6000
Client connects to proxy ✅

Folder Structure 

ReverseProxyDemo/
 ├── SignalRServer        // .NET real-time server
 ├── ReverseProxy         // YARP proxy
 └── SignalRClient        // Console test client
Enter fullscreen mode Exit fullscreen mode

Code — SignalR Server (/SignalRServer/Program.cs) 

using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.SignalR;

var builder = WebApplication.CreateBuilder(args);
builder.Services.AddSignalR();
var app = builder.Build();
app.MapGet("/", () => "SignalR Server Running");
app.MapHub<ChatHub>("/hub/chat");
app.Run();

public class ChatHub : Hub { }
Enter fullscreen mode Exit fullscreen mode

Code — YARP Reverse Proxy (/ReverseProxy/Program.cs) 

var builder = WebApplication.CreateBuilder(args);
builder.Services.AddReverseProxy().LoadFromConfig(builder.Configuration.GetSection("ReverseProxy"));
var app = builder.Build();
app.MapReverseProxy();
app.Run();
Enter fullscreen mode Exit fullscreen mode

appsettings.json 

{
  "ReverseProxy": {
    "Routes": {
      "signalrRoute": {
        "ClusterId": "signalrCluster",
        "Match": { "Path": "/hub/{**catch-all}" }
      }
    },
    "Clusters": {
      "signalrCluster": {
        "Destinations": {
          "destination1": { "Address": "http://localhost:5000" }
        }
      }
    }
  }
}
Enter fullscreen mode Exit fullscreen mode

Code — Client (/SignalRClient/Program.cs) 

using Microsoft.AspNetCore.SignalR.Client;
Console.WriteLine("Client connecting...");
var connection = new HubConnectionBuilder()
    .WithUrl("http://localhost:6000/hub/chat")
    .Build();
await connection.StartAsync();
Console.WriteLine("Connected to SignalR via Reverse Proxy!");
Enter fullscreen mode Exit fullscreen mode

Running the project

Start SignalR server 

cd SignalRServer
dotnet run --urls=http://localhost:5000
Enter fullscreen mode Exit fullscreen mode

Start Reverse Proxy 

cd ReverseProxy
dotnet run --urls=http://localhost:6000
Enter fullscreen mode Exit fullscreen mode

Start Client 

cd SignalRClient
dotnet run
Enter fullscreen mode Exit fullscreen mode

Output:

Client connecting...
Connected to SignalR via Reverse Proxy!
Enter fullscreen mode Exit fullscreen mode

Download Full Source Code (ZIP)

Link: (https://github.com/Morteza-Jangjoo/Reverse_Proxy)

This ZIP contains all three projects ready to run.

Conclusion

Reverse Proxy is essential in modern .NET architectures — especially when building real-time SignalR apps.

With YARP you get:

WebSockets support
Load balancing
Easy routing
Production-ready reverse proxy

Next Step

Want the same setup with:

  • Docker + Nginx
  • Angular real-time dashboard
  • Kubernetes setup

Comment below and I’ll publish part 2

💬 Feedback

If this helped you, drop a ❤️ and follow for more .NET + Realtime + Cloud tutorials.

Top comments (0)