apmgokit

package main

import (
	"context"

	kitgrpc "github.com/go-kit/kit/transport/grpc"
	"google.golang.org/grpc"

	pb "google.golang.org/grpc/examples/helloworld/helloworld"

	"go.elastic.co/apm"
	"go.elastic.co/apm/module/apmgrpc"
)

func main() {
	// When dialling the gRPC client connection, use the apmgrpc.NewUnaryClientInterceptor
	// function (from module/apmgrpc). This will trace all outgoing requests, as long as
	// the context supplied to methods include an apm.Transaction.
	conn, err := grpc.Dial("localhost:1234", grpc.WithUnaryInterceptor(apmgrpc.NewUnaryClientInterceptor()))
	if err != nil {
		panic(err)
	}
	defer conn.Close()

	// Create your go-kit/kit/transport/grpc.Client as usual, without any tracing middleware.
	client := kitgrpc.NewClient(
		conn, "helloworld.Greeter", "SayHello",
		func(ctx context.Context, req interface{}) (interface{}, error) {
			return &pb.HelloRequest{Name: req.(string)}, nil
		},
		func(ctx context.Context, resp interface{}) (interface{}, error) {
			return resp, nil
		},
		&pb.HelloReply{},
	)

	tx := apm.DefaultTracer.StartTransaction("name", "type")
	ctx := apm.ContextWithTransaction(context.Background(), tx)
	defer tx.End()

	_, err = client.Endpoint()(ctx, "world")
	if err != nil {
		panic(err)
	}
}

Output:

package main

import (
	"context"
	"net"

	kitgrpc "github.com/go-kit/kit/transport/grpc"

	netcontext "golang.org/x/net/context"
	"google.golang.org/grpc"

	pb "google.golang.org/grpc/examples/helloworld/helloworld"

	"go.elastic.co/apm"
	"go.elastic.co/apm/module/apmgrpc"
)

func main() {
	// Create your go-kit/kit/transport/grpc.Server as usual, without any tracing middleware.
	endpoint := func(ctx context.Context, req interface{}) (interface{}, error) {
		// The middleware added to the underlying gRPC server will be propagate
		// a transaction to the context passed to your endpoint. You can then
		// report endpoint-specific spans using apm.StartSpan.
		span, ctx := apm.StartSpan(ctx, "name", "endpoint")
		defer span.End()
		return nil, nil
	}
	var encodeRequest func(ctx context.Context, req interface{}) (interface{}, error)
	var decodeResponse func(ctx context.Context, req interface{}) (interface{}, error)
	service := &helloWorldService{kitgrpc.NewServer(
		endpoint,
		encodeRequest,
		decodeResponse,
	)}

	// When creating the underlying gRPC server, use the apmgrpc.NewUnaryServerInterceptor
	// function (from module/apmgrpc). This will trace all incoming requests.
	s := grpc.NewServer(grpc.UnaryInterceptor(apmgrpc.NewUnaryServerInterceptor()))
	defer s.GracefulStop()
	lis, err := net.Listen("tcp", "localhost:0")
	if err != nil {
		panic(err)
	}
	go s.Serve(lis)
	pb.RegisterGreeterServer(s, service)
}

type helloWorldService struct {
	sayHello *kitgrpc.Server
}

func (s *helloWorldService) SayHello(ctx netcontext.Context, req *pb.HelloRequest) (*pb.HelloReply, error) {
	_, rep, err := s.sayHello.ServeGRPC(ctx, req)
	if err != nil {
		return nil, err
	}
	return rep.(*pb.HelloReply), nil
}

Output:

package main

import (
	"context"
	"net/http"
	"net/url"

	kithttp "github.com/go-kit/kit/transport/http"

	"go.elastic.co/apm"
	"go.elastic.co/apm/module/apmhttp"
)

func main() {
	// When constructing the kit/transport/http.Client, pass in an http.Client
	// instrumented using apmhttp.WrapClient (from module/apmhttp). This will
	// trace all outgoing requests, as long as the context supplied to methods
	// include an apm.Transaction.
	client := kithttp.NewClient(
		"GET", &url.URL{ /*...*/ },
		kithttp.EncodeJSONRequest,
		func(_ context.Context, r *http.Response) (interface{}, error) { return nil, nil },
		kithttp.SetClient(apmhttp.WrapClient(http.DefaultClient)),
	)

	tx := apm.DefaultTracer.StartTransaction("name", "type")
	ctx := apm.ContextWithTransaction(context.Background(), tx)
	defer tx.End()

	_, err := client.Endpoint()(ctx, struct{}{})
	if err != nil {
		panic(err)
	}
}

Output:

package main

import (
	"context"
	"net/http"

	kithttp "github.com/go-kit/kit/transport/http"

	"go.elastic.co/apm"
	"go.elastic.co/apm/module/apmhttp"
)

func main() {
	// Create your go-kit/kit/transport/http.Server as usual, without any tracing middleware.
	endpoint := func(ctx context.Context, req interface{}) (interface{}, error) {
		// The middleware added to the underlying gRPC server will be propagate
		// a transaction to the context passed to your endpoint. You can then
		// report endpoint-specific spans using apm.StartSpan.
		span, ctx := apm.StartSpan(ctx, "name", "endpoint")
		defer span.End()
		return nil, nil
	}
	server := kithttp.NewServer(
		endpoint,
		kithttp.NopRequestDecoder,
		func(_ context.Context, w http.ResponseWriter, _ interface{}) error { return nil },
	)

	// Use apmhttp.Wrap (from module/apmhttp) to instrument the
	// kit/transport/http.Server. This will trace all incoming requests.
	http.ListenAndServe("localhost:1234", apmhttp.Wrap(server))
}

Output: