membership input validation improved & tests

internal/controllers/membershipController.go

@@ -3,6 +3,7 @@ package controllers
 import (
 	"GoMembership/internal/models"
 	"GoMembership/internal/services"
+	"strings"
 
 	"net/http"
 	// "strconv"
@@ -31,7 +32,11 @@ func (mc *MembershipController) RegisterSubscription(c *gin.Context) {
 	id, err := mc.Service.RegisterSubscription(&regData.Model)
 	if err != nil {
 		logger.Error.Printf("Couldn't register Membershipmodel: %v", err)
-		c.JSON(int(id), "Couldn't register Membershipmodel")
+		if strings.Contains(err.Error(), "UNIQUE constraint failed") {
+			c.JSON(http.StatusConflict, "Duplicate subscription name")
+			return
+		}
+		c.JSON(http.StatusNotAcceptable, "Couldn't register Membershipmodel")
 		return
 	}
 	logger.Info.Printf("registering subscription: %+v", regData)