otelgraphql

README

OpenTelemetry Go instrumentation for the graphql-go GraphQL Server

This instrumentation records GraphQL operations using OpenTelemetry API.

Installation

go get github.com/rlakhtakia/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/rlakhtakia/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.

Documentation

Index

• func Version() string
• type Option
  • func WithTracerProvider(provider oteltrace.TracerProvider) Option
• type Tracer
  • func NewTracer(opts ...Option) *Tracer
  • func (t Tracer) TraceField(ctx context.Context, label, typeName, fieldName string, trivial bool, ...) (context.Context, tracer.FieldFinishFunc)
  • func (t Tracer) TraceQuery(ctx context.Context, queryString string, operationName string, ...) (context.Context, tracer.QueryFinishFunc)
  • func (t Tracer) TraceValidation(ctx context.Context) tracer.ValidationFinishFunc

Functions

func Version

func Version() string

Version is the current release version.

Types

type Option

type Option interface {
	// contains filtered or unexported methods
}

Option specifies instrumentation configuration options.

func WithTracerProvider

func WithTracerProvider(provider oteltrace.TracerProvider) Option

WithTracerProvider specifies a tracer provider to use for creating a tracer. If none is specified, the global provider is used.

type Tracer

type Tracer struct {
	// contains filtered or unexported fields
}

func NewTracer

func NewTracer(opts ...Option) *Tracer

func (Tracer) TraceField

func (t Tracer) TraceField(
	ctx context.Context,
	label,
	typeName,
	fieldName string,
	trivial bool,
	args map[string]interface{},
) (context.Context, tracer.FieldFinishFunc)

func (Tracer) TraceQuery

func (t Tracer) TraceQuery(
	ctx context.Context,
	queryString string, operationName string,
	variables map[string]interface{},
	_ map[string]*introspection.Type,
) (context.Context, tracer.QueryFinishFunc)

func (Tracer) TraceValidation

func (t Tracer) TraceValidation(ctx context.Context) tracer.ValidationFinishFunc