HotChocolate OpenTelemetry

HotChocolate remains my favorite GraphQL client for .NET. As I find it really important to monitor my applications, I have written multiple posts(hereand here) on how to integrate monitoring with HotChocolate.

At the beginning of this year, with the release of HotChocolate 12.5, support for OpenTelemetry was introduced. Although I updated my applications to start using it, it took me until now to write a corresponding blog post about it.

Instrument your GraphQL Server with OpenTelemetry

Let me walk you through the steps:

• We’ll start with an ASP.NET Core application with OpenTelemetry enabled. Therefore we added the following NuGet packages:
• OpenTelemetry.Extensions.Hosting
• OpenTelemetry.Instrumentation.AspNetCore
• OpenTelemetry.Instrumentation.Http
• OpenTelemetry.Instrumentation.SqlClient
• We also add a reference to the AzureMonitor exporter because we want to use Application Insights:
• Azure.Monitor.OpenTelemetry.Exporter
• Of course we need to add some code to enable OpenTelemetry:

	var api = ResourceBuilder.CreateEmpty()
	.AddService("Example-Service")
	.AddAttributes(new KeyValuePair<string, object>[]
	{
	new("development.environment",""),
	new("telemetry.sdk.name","dotnet"),
	new("telemetry.sdk.version","6.0.0"),
	});
	builder.Services.AddOpenTelemetryTracing(b =>
	{
	b.AddHttpClientInstrumentation();
	b.AddAspNetCoreInstrumentation();
	b.AddSqlClientInstrumentation(options => {
	options.SetDbStatementForText = true;
	});
	b.SetResourceBuilder(api);
	b.AddAzureMonitorTraceExporter(options =>
	{
	options.ConnectionString = Configuration.GetSection("ApplicationInsights").GetValue<string>("ConnectionString");
	});
	});

view raw Program.cs hosted with ❤ by GitHub

•   Everything we need to use OpenTelemetry with HotChocolate can be found in the following NuGet package:
• HotChocolate.Diagnostics
• After you have installed this package, we can extend the OpenTelemetry configuration:

	builder.Services.AddOpenTelemetryTracing(b =>
	{
	b.SetResourceBuilder(api);
	//Add GraphQL instrumentation
	b.AddHotChocolateInstrumentation();
	//Removed the other code
	});

view raw Program.cs hosted with ❤ by GitHub

• Almost there! As a last step, we need to update our GraphQL Server configuration:

	builder.Services.AddGraphQLServer()
	.AddQueryType<QueryType>()
	.AddInstrumentation(o => {
	o.RenameRootActivity = true;
	o.IncludeDocument = true;
	o.Scopes = ActivityScopes.All;
	})
	.AddApolloTracing(HotChocolate.Execution.Options.TracingPreference.OnDemand);

view raw Program.cs hosted with ❤ by GitHub

• Let me explain the settings I’m using a little bit more:
• Scopes: Allows you to specify which subscopes should be included in the trace data. I’ve set this to ‘ActivityScopes.All’ in this example but know that you can control this. Be aware that adding extra scopes has a performance impact. 
• RenameRootActivity: By setting this to ‘true’ the the Operation display name will be shown as part of the root activity.
• IncludeDocument: By setting this to ‘true’ the parsed document will be included in the trace data.

If we now have a look at how this arrives in Application Insights, you see that you get full traceability:

And if you look at a specific trace message, you get all the details:

More information: https://chillicream.com/docs/hotchocolate/server/instrumentation#opentelemetry