photos/internal/httphelpers/error.go

package httphelpers

import (
	"errors"
	"fmt"
	"net/http"

	"github.com/minio/minio-go/v6"
)

var ErrorBadRequest = errors.New("bad request")
var ErrorMethodNotAllowed = errors.New("method not allowed")
var ErrorNotFound = errors.New("not found")
var ErrorUnauthorized = errors.New("unauthorized")

func ErrorResponse(w http.ResponseWriter, err error) {
	if err == nil {
		panic("Sneaky, you called ErrorResponse without an error. I shall destroy you")
	}
	errorMessage := err.Error()
	errorStatus := http.StatusInternalServerError

	if errors.Is(err, ErrorBadRequest) {
		errorStatus = http.StatusBadRequest
	}
	if errors.Is(err, ErrorMethodNotAllowed) {
		errorStatus = http.StatusMethodNotAllowed
	}
	if errors.Is(err, ErrorNotFound) {
		errorStatus = http.StatusNotFound
	}

	var minioErrorResponse minio.ErrorResponse
	if errors.As(err, &minioErrorResponse) {
		if minioErrorResponse.Code == "NoSuchKey" {
			errorStatus = http.StatusNotFound
		}
		if minioErrorResponse.Code == "NoSuchBucket" {
			errorStatus = http.StatusNotFound
		}
		// Do not handle MinIO AccessDenied: that's a server error. Our credentials should always be correct
	}

	// Let Header.Write() handle escaping
	w.Header().Add("X-Debug-Error", errorMessage)
	w.WriteHeader(errorStatus)
}

func ErrorFromStatus(code int) error {
	if code == http.StatusOK {
		return nil
	}
	if code == http.StatusNotFound {
		return ErrorNotFound
	}
	if code == http.StatusBadRequest {
		return ErrorBadRequest
	}
	if code == http.StatusUnauthorized {
		return ErrorUnauthorized
	}
	return fmt.Errorf("%s", http.StatusText(code))
}