idempotency.go

package main

import (
	"context"
	"encoding/json"
	"fmt"
	"io/ioutil"
	"net/http"
	"net/http/httptest"
	"sync"
	"time"

	"github.com/adyen/adyen-go-api-library/v2/src/adyen"
	"github.com/adyen/adyen-go-api-library/v2/src/checkout"
	"github.com/adyen/adyen-go-api-library/v2/src/common"
	"github.com/google/uuid"
)

type requestLogger struct{}

func (rl *requestLogger) RoundTrip(req *http.Request) (*http.Response, error) {
	body, _ := ioutil.ReadAll(req.Body)
	data := map[string]interface{}{}
	json.Unmarshal(body, &data)
	reference := data["reference"]
	idempotencyKey := req.Header.Get("Idempotency-Key")
	if reference != idempotencyKey {
		fmt.Printf("Request body %s had idempotencyKey %s", reference, idempotencyKey)
	}
	resp := httptest.NewRecorder()
	resp.WriteHeader(http.StatusOK)
	return resp.Result(), nil
}

func main() {
	client := adyen.NewClient(&common.Config{
		HTTPClient: &http.Client{
			Transport: &requestLogger{},
		},
	})

	s := &http.Server{
		Addr: ":8080",
		Handler: http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
			idempotencyKey := uuid.Must(uuid.NewRandom()).String()
			client.SetIdempotencyKey(idempotencyKey)
			client.Checkout.Payments(&checkout.PaymentRequest{
				Reference: idempotencyKey,
			})
			w.WriteHeader(http.StatusOK)

		}),
		ReadTimeout:    10 * time.Second,
		WriteTimeout:   10 * time.Second,
		MaxHeaderBytes: 1 << 20,
	}
	go s.ListenAndServe()

	wg := &sync.WaitGroup{}
	wg.Add(10)
	for r := 0; r < 10; r++ {
		fmt.Printf("Routine #%d", r)
		go func() {
			for i := 0; i < 100; i++ {
				fmt.Printf("Req#%d.%d", r, i)
				http.Get("http://localhost:8080")
			}
			wg.Done()
		}()
	}
	wg.Wait()
	ctx, cancel := context.WithTimeout(context.Background(), time.Second*5)
	defer cancel()
	s.Shutdown(ctx)
}