emf-aws-client-gist.go

package main

import (
	"context"
	"time"

	"github.com/aws/aws-lambda-go/lambda"
	"github.com/aws/aws-sdk-go/aws/request"
	"github.com/aws/aws-sdk-go/aws/session"
	"github.com/prozz/aws-embedded-metrics-golang/emf"
)

func handler(ctx context.Context, event MyEvent) (string, error) {
	_, _ = getAwsSession()
	// do something with the AWS session
	return "done", nil
}

func main() {
	lambda.Start(handler)
}

type MyEvent struct {
	URL string `json:"url"`
}

func getAwsSession() (*session.Session, error) {
	s, e := session.NewSession()
	if e != nil {
		return nil, e
	}

	s.Handlers.Complete.PushFrontNamed(request.NamedHandler{
		Name: "MetricHandler",
		Fn: func(r *request.Request) {
			m := emf.New().Namespace("CustomNamespace")
			defer m.Log()

			m.DimensionSet(
				emf.NewDimension("Endpoint", r.ClientInfo.ServiceName),
				emf.NewDimension("Operation", r.Operation.Name)).
				MetricFloatAs("Duration", float64(time.Since(r.AttemptTime).Milliseconds()), emf.Milliseconds)
		},
	})

	return s, nil
}