OTEL Instrumentation on Subgraphs

How to setup OTEL instrumentation on subgraphs.

The steps to instrument the subgraphs are as follows:

1. Instrument your application with OpenTelemetry.

2. Ensure you define a unique serviceName.

3. If you’re running on Cosmo Cloud, the OTEL endpoint is https://cosmo-otel.wundergraph.com

4. Set the endpoint URL path to /v1/traces (Usually the default)

5. To authenticate against the collector, make your OpenTelemetry agent authenticate using your federated graph token as a bearer token, by adding the following HTTP header: Authorization: Bearer <your token>

Examples

Go

client := otlptracehttp.NewClient(
    otlptracehttp.WithEndpoint("https://cosmo-otel.wundergraph.com"),
    otlptracehttp.WithHeaders(map[string]string{
        "Authorization": "Bearer <secret>",
    }),
)

tp := sdktrace.NewTracerProvider(
    sdktrace.WithResource(resource.NewSchemaless(semconv.ServiceNameKey.String(otelOpts.ServiceName))),
    sdktrace.WithSampler(
	sdktrace.ParentBased(
    	    sdktrace.TraceIDRatioBased(c.Sampler),
    	    // When the parent span is sampled, the child span will be sampled.
    	),
    ),
)

TypeScript

import { OTLPTraceExporter } from "@opentelemetry/exporter-trace-otlp-proto";

// Set OTEL_HTTP_ENDPOINT to https://cosmo-otel.wundergraph.com
// Set OTEL_AUTH_TOKEN to your graph authentication token
const otelAuthToken = process.env.OTEL_AUTH_TOKEN;
const otlpExporterHeaders = otelAuthToken
  ? { Authorization: `Bearer ${otelAuthToken}` }
  : undefined;

const otlpExporter = new OTLPTraceExporter({
  url: process.env.OTEL_HTTP_ENDPOINT,
  headers: otlpExporterHeaders,
});

Sampling Rate

Ensure that your subgraphs use parent-based sampling to inherit the sampling rate.

Example

Additionally, check our TypeScript example with OTEL.

Custom OTEL Metrics are currently not exposed but stored. Please contact us if you have advanced use cases.