feat: custom claims (#53)

backend/internal/middleware/error_handler.go

@@ -0,0 +1,101 @@
+package middleware
+
+import (
+	"errors"
+	"fmt"
+	"github.com/gin-gonic/gin"
+	"github.com/gin-gonic/gin/binding"
+	"github.com/go-playground/validator/v10"
+	"github.com/stonith404/pocket-id/backend/internal/common"
+	"gorm.io/gorm"
+	"log"
+	"net/http"
+	"strings"
+)
+
+type ErrorHandlerMiddleware struct{}
+
+func NewErrorHandlerMiddleware() *ErrorHandlerMiddleware {
+	return &ErrorHandlerMiddleware{}
+}
+
+func (m *ErrorHandlerMiddleware) Add() gin.HandlerFunc {
+	return func(c *gin.Context) {
+		c.Next()
+		for _, err := range c.Errors {
+
+			// Check for record not found errors
+			if errors.Is(err, gorm.ErrRecordNotFound) {
+				errorResponse(c, http.StatusNotFound, "Record not found")
+				return
+			}
+
+			// Check for validation errors
+			var validationErrors validator.ValidationErrors
+			if errors.As(err, &validationErrors) {
+				message := handleValidationError(validationErrors)
+				errorResponse(c, http.StatusBadRequest, message)
+				return
+			}
+
+			// Check for slice validation errors
+			var sliceValidationErrors binding.SliceValidationError
+			if errors.As(err, &sliceValidationErrors) {
+				if errors.As(sliceValidationErrors[0], &validationErrors) {
+					message := handleValidationError(validationErrors)
+					errorResponse(c, http.StatusBadRequest, message)
+					return
+				}
+			}
+
+			var appErr common.AppError
+			if errors.As(err, &appErr) {
+				errorResponse(c, appErr.HttpStatusCode(), appErr.Error())
+				return
+			}
+
+			log.Println(err)
+			c.JSON(http.StatusInternalServerError, gin.H{"error": "Something went wrong"})
+		}
+	}
+}
+
+func errorResponse(c *gin.Context, statusCode int, message string) {
+	// Capitalize the first letter of the message
+	message = strings.ToUpper(message[:1]) + message[1:]
+	c.JSON(statusCode, gin.H{"error": message})
+}
+
+func handleValidationError(validationErrors validator.ValidationErrors) string {
+	var errorMessages []string
+
+	for _, ve := range validationErrors {
+		fieldName := ve.Field()
+		var errorMessage string
+		switch ve.Tag() {
+		case "required":
+			errorMessage = fmt.Sprintf("%s is required", fieldName)
+		case "email":
+			errorMessage = fmt.Sprintf("%s must be a valid email address", fieldName)
+		case "username":
+			errorMessage = fmt.Sprintf("%s must only contain lowercase letters, numbers, underscores, dots, hyphens, and '@' symbols and not start or end with a special character", fieldName)
+		case "url":
+			errorMessage = fmt.Sprintf("%s must be a valid URL", fieldName)
+		case "min":
+			errorMessage = fmt.Sprintf("%s must be at least %s characters long", fieldName, ve.Param())
+		case "max":
+			errorMessage = fmt.Sprintf("%s must be at most %s characters long", fieldName, ve.Param())
+		case "urlList":
+			errorMessage = fmt.Sprintf("%s must be a list of valid URLs", fieldName)
+		default:
+			errorMessage = fmt.Sprintf("%s is invalid", fieldName)
+		}
+
+		errorMessages = append(errorMessages, errorMessage)
+	}
+
+	// Join all the error messages into a single string
+	combinedErrors := strings.Join(errorMessages, ", ")
+
+	return combinedErrors
+}