1 files changed, 17 insertions, 0 deletions
diff --git a/BackEnd/Timeline/Services/User/UserServiceExtensions.cs b/BackEnd/Timeline/Services/User/UserServiceExtensions.cs
new file mode 100644
index 00000000..82b55fba
--- /dev/null
+++ b/BackEnd/Timeline/Services/User/UserServiceExtensions.cs
@@ -0,0 +1,17 @@
+using System.Collections.Generic;
+using System.Threading.Tasks;
+
+namespace Timeline.Services.User
+{
+    public static class UserServiceExtensions
+    {
+        public static async Task ThrowIfUserNotExist(this IUserService service, long userId)
+        {
+            if (!await service.CheckUserExistenceAsync(userId))
+            {
+                throw new EntityNotExistException(EntityTypes.User,
+                    new Dictionary<string, object> { ["id"] = userId });
+            }
+        }
+    }
+}