otelgraphql

OpenTelemetry Go instrumentation for the graphql-go GraphQL Server

This instrumentation records GraphQL operations using OpenTelemetry API.

Installation

go get github.com/uptrace/opentelemetry-go-extra/otelgraphql

Usage

graphql-go already provides a tracer interface along with its respective opentracing implementation This interface consists of the following methods, all of which get context.Context as a parameter:

TraceValidation: traces the schema validation step which precedes the actual operation.

TraceQuery: traces the actual operation, query or mutation, as a whole

TraceField: traces a field-specific operation; its span should typically be a sub-span of the TraceQuery one;

otelgraphql provides an implementation of this interface, which is practically a port of the opentracing one that comes pre-packaged with graphql-go.

Some other points:

1. graphql-go exposes a single HTTP Handler for all graphql operations. That makes it a natural fit for otelhttp and other router packages instrumentation, if propagating frontend baggage (e.g. headers) is required.
2. graphql-go resolver methods do get context.Context as a parameter, which allows for field-specific (sub-)span creation, if TraceQuery does not suffice.

import (
  "context"
  "log"
  "net/http"

  "github.com/graph-gophers/graphql-go"
  "github.com/graph-gophers/graphql-go/relay"

  "github.com/uptrace/opentelemetry-go-extra/otelgraphql"
)

tracer := otelgraphql.NewTracer(otelgraphql.WithTracerProvider(traceProvider))

opts := []graphql.SchemaOpt{
  graphql.Tracer(tracer),
}
schema = graphql.MustParseSchema(schemaString, &RootResolver{}, opts...)

http.Handle("/graphql", &relay.Handler{Schema: schema})

log.Fatal(http.ListenAndServe(":8080", nil))

See example for details.