lucifer/internal/httperr/error.go

package httperr

import (
	"fmt"
	"log"
	"net/http"
	"strconv"
	"time"

	"git.aiterp.net/lucifer/lucifer/internal/respond"
	"github.com/google/uuid"
)

// Error is an error that can be used.
type Error struct {
	Status  int
	Kind    string
	Message string
}

func (err Error) Error() string {
	return err.Kind + ": " + err.Message
}

// ErrLoginRequired is a common error for when a session is expected, but none is found.
var ErrLoginRequired = Error{Status: 401, Kind: "login_required", Message: "You are not logged in."}

// ErrAccessDenied is a common error for when a session is expected, but none is found.
var ErrAccessDenied = Error{Status: 403, Kind: "access_denied", Message: "You cannot do that."}

// NotFound generates a 404 error.
func NotFound(model string) Error {
	return Error{Status: 404, Kind: "not_found", Message: model + " not found"}
}

// Respond responds with the error using the format in the `respond` package. If
// the error is not a httperr.Error, then it'll be logged and a 500 will be returned.
func Respond(w http.ResponseWriter, err error) {
	if httpErr, ok := err.(Error); ok {
		respond.Error(w, httpErr.Status, httpErr.Kind, httpErr.Message)
	} else {
		errIDStr := ""
		errID, err2 := uuid.NewRandom()
		if err2 != nil {
			errID, err2 = uuid.NewUUID()
			if err2 != nil {
				errIDStr = strconv.FormatInt(time.Now().UnixNano(), 36)
			} else {
				errIDStr = errID.String()
			}
		} else {
			errIDStr = errID.String()
		}

		log.Printf("ERROR [%s]: %s", errIDStr, err.Error())
		respond.Error(w, 500, "internal_error", fmt.Sprintf("Something went wrong. It has been logged with the ID %s", errIDStr))
	}
}