エラー処理

package main

import (
  "github.com/stripe/stripe-go/v72"
  "github.com/stripe/stripe-go/v72/paymentintent"
  "log"
)

func example_function(params *stripe.PaymentIntentParams) {
  stripe.Key = 
"sk_test_BQokikJOvBiI2HlWgH4olfQ2"
  _, err := paymentintent.New(params)
  if err == nil {
    log.Println("No error.")
  } else {
    if stripeErr, ok := err.(*stripe.Error); ok {
      switch stripeErr.Type {
        case stripe.ErrorTypeCard:
          log.Println("A payment error occurred:", stripeErr.Msg)
        case stripe.ErrorTypeInvalidRequest:
          log.Println("An invalid request occurred.")
        default:
          log.Println("Another Stripe error occurred.")
      }
    } else {
      log.Println("An error occurred that was unrelated to Stripe.")
    }
  }
}

package main

import (
  "encoding/json"
  "io/ioutil"
  "log"
  "net/http"

  "github.com/stripe/stripe-go/v72"
  "github.com/stripe/stripe-go/v72/webhook"
)

func main() {
  http.HandleFunc("/webhook", handleWebhook)
  addr := "localhost:4242"
  log.Printf("Listening on %s", addr)
  log.Fatal(http.ListenAndServe(addr, nil))
}

func handleWebhook(w http.ResponseWriter, req *http.Request) {
  const MaxBodyBytes = int64(65536)
  req.Body = http.MaxBytesReader(w, req.Body, MaxBodyBytes)
  payload, err := ioutil.ReadAll(req.Body)
  if err != nil {
    log.Printf("Error reading request body: %v\n", err)
    w.WriteHeader(http.StatusServiceUnavailable)
    return
  }

  // Replace this endpoint secret with your endpoint's unique secret
  // If you are testing with the CLI, find the secret by running 'stripe listen'
  // If you are using an endpoint defined with the API or dashboard, look in your webhook settings
  // at https://dashboard.stripe.com/webhooks
  endpointSecret := "whsec_..."
  signatureHeader := req.Header.Get("Stripe-Signature")

  // Get an event object
  event, err := webhook.ConstructEvent(payload, signatureHeader, endpointSecret)
  if err != nil {
    log.Printf("⚠️  Webhook signature verification failed. %v\n", err)
    w.WriteHeader(http.StatusBadRequest) // Return a 400 error on a bad signature
    return
  }
  // Use its type to find out what happened
  switch event.Type {
  case "payment_intent.payment_failed":

    // Get the object affected by unmarshalling event data into
    // the appropriate struct for the event type
    var paymentIntent stripe.PaymentIntent
    err := json.Unmarshal(event.Data.Raw, &paymentIntent)
    if err != nil {
      log.Printf("Error parsing webhook JSON: %v\n", err)
      w.WriteHeader(http.StatusBadRequest)
      return
    }

    // Use stored data to get an error object
    e := paymentIntent.LastPaymentError

    // Use its type to choose a response
    switch e.Type {
    case "card_error":
      log.Println("A payment error occurred: ", e.Msg)
    case "invalid_request":
      log.Println("An invalid request occurred.")
    default:
      log.Println("Another problem occurred, maybe unrelated to Stripe.")
    }
  default:
    log.Println("Unhandled event type: ", event.Type)
  }

  w.WriteHeader(http.StatusOK)
}

stripe.Key = 
"sk_test_BQokikJOvBiI2HlWgH4olfQ2"

pi, _ := paymentintent.Get(
  
"{{PAYMENT_INTENT_ID}}",
  nil,
)
paymentErr := pi.LastPaymentError
if paymentErr != nil {
  log.Printf("PaymentIntent %s experienced a %s error.", pi.ID, paymentErr.Type)
}