Adliance.AspNetCore.Buddy.OpenTelemetry 8.0.0.9

Adliance.AspNetCore.Buddy.OpenTelemetry

The OpenTelemetry Buddy makes instrumentation of ASP.NET Core web services easy.

Features

• Frontend instrumentation
• Backend instrumentation
• Background jobs with Hangfire

Setup library in an ASP.NET project

The package offers the AddBuddyOpenTelemetry extensions to add the instrumentation and exporter.

using Adliance.AspNetCore.Buddy.OpenTelemetry.Extensions;

// ...

public void ConfigureServices(IServiceCollection services)
{
  //...
  services.AddBuddyOpenTelemetry(Configuration.GetSection("OpenTelemetry"))    
  // if you use Hangfire, also add
  services.AddBuddyOpenTelemetryHangfire(Configuration.GetSection("OpenTelemetry"));
}

public void Configure(IApplicationBuilder app)
{
    // if you want to instrument the frontend
    app.UseBuddyOpenTelemetryBrowserAssets();
}

To also send log messages from Microsoft.Extensions.Logging, the package offers another AddBuddyOpenTelemetry extension.

using Adliance.AspNetCore.Buddy.OpenTelemetry.Extensions;

// ...

public static IHostBuilder CreateHostBuilder(string[] args) =>
    Host.CreateDefaultBuilder(args)
        .ConfigureWebHostDefaults(webBuilder =>
        {
            webBuilder.UseStartup<Startup>();
            webBuilder.ConfigureLogging((context, builder) =>
            {
                builder.AddBuddyOpenTelemetry(context.Configuration.GetSection("OpenTelemetry"));
            });
        });

Configuration (appsettings.json)

Add a section in the configuration of your project and add at least the following configuration:

{
  "OpenTelemetry": {
    "ServiceName": "example server"
  }
}

It is also possible to overwrite defaults for the exporter like this:

{
  "OpenTelemetry": {
    "ServiceName": "example server",
    "OtlpExporter": {
      "Endpoint": "http://localhost:4317",
      "Protocol": "0", // 0 ... gRPC, 1 ... http/protobuf
      "Headers": "X-Api-Key=123,X-Api-Version=1.0",
      "TimeoutMilliseconds": 60000
    }
  }
}

Frontend instrumentation

It is important to pass a trace parent to the frontend tracing SDK, such that the spans can be grouped together later on. This can be achieved by adding a meta tag to the head section of the HTML by

1. Adding the following code to _ViewImports.cshtml:

@inject Adliance.AspNetCore.Buddy.OpenTelemetry.HtmlHelper OtelHtmlHelper

2. Adding the following in the head section of your _Layout.cshtml before closing the body section:

@Html.Raw(OtelHtmlHelper.TraceParentTag)

The UseBuddyOpenTelemetryBrowserAssets extension method adds a middleware to serve the necessary JavaScript file at the /otel-$version/telemetry.js endpoint. This must also be referenced in your _Layout.cshtml:

@Html.Raw(OtelHtmlHelper.IncludeAndInitializeJavascript)


<script>
    
    window.buddyTelemetry.traceSpan("example span", () => "the result");
</script>