AspNetCore.SignalR.OpenTelemetry

This is an Instrumentation Library, which instruments ASP.NET Core SignalR and collect traces about SignalR hub method invocations.

Table of Contents

• Install
• Usage
• Example
• Related Work

Install

NuGet: AspNetCore.SignalR.OpenTelemetry

dotnet add package AspNetCore.SignalR.OpenTelemetry

Usage

var builder = WebApplication.CreateBuilder(args);

builder.Services.AddSignalR()
    .AddHubInstrumentation(); // <- Add this!

builder.Services.AddOpenTelemetry()
    .ConfigureResource(builder =>
    {
        builder.AddService("AspNetCore.SignalR.OpenTelemetry.Example");
    })
    .WithTracing(providerBuilder =>
    {
        providerBuilder
            .AddAspNetCoreInstrumentation()
            .AddSignalRInstrumentation() // <- Add this!
            .AddOtlpExporter();
    });

Example

The example code architecture is as follows.

graph LR;
    app[ASP.NET Core Server] --> otelc[OpenTelemetry Collector];
    otelc --> Tempo;
    Grafana --> Tempo;

Loading

The example code can be quickly executed from Visual Studio.

It can also be quickly executed from the CLI.

$ docker compose build
$ docker compose up

• App Server: http://localhost:8080/signalr-dev/index.html
• Grafana: http://localhost:3000/explore

In Grafana, you can see the SignalR method call trace as follows.

Related Work

• nenoNaninu/TypedSignalR.Client
  • C# Source Generator to create strongly typed SignalR clients.
• nenoNaninu/TypedSignalR.Client.TypeScript
  • TypeScript source generator to provide strongly typed SignalR clients by analyzing C# type definitions.
• nenoNaninu/TypedSignalR.Client.DevTools
  • SignalR development tools inspired by SwaggerUI.