1 files changed, 51 insertions, 0 deletions
diff --git a/Timeline/Models/Http/Common.cs b/Timeline/Models/Http/Common.cs
new file mode 100644
index 00000000..74959088
--- /dev/null
+++ b/Timeline/Models/Http/Common.cs
@@ -0,0 +1,51 @@
+namespace Timeline.Models.Http
+{
+    public class CommonResponse
+    {
+        public static class ErrorCodes
+        {
+            /// <summary>
+            /// Used when the model is invaid.
+            /// For example a required field is null.
+            /// </summary>
+            public const int InvalidModel = -100;
+        }
+
+        public static CommonResponse InvalidModel(string message)
+        {
+            return new CommonResponse(ErrorCodes.InvalidModel, message);
+        }
+
+        public CommonResponse()
+        {
+
+        }
+
+        public CommonResponse(int code, string message)
+        {
+            Code = code;
+            Message = message;
+        }
+
+        public int Code { get; set; }
+        public string Message { get; set; }
+    }
+
+    public static class CommonPutResponse
+    {
+        public const int CreatedCode = 0;
+        public const int ModifiedCode = 1;
+
+        public static CommonResponse Created { get; } = new CommonResponse(CreatedCode, "A new item is created.");
+        public static CommonResponse Modified { get; } = new CommonResponse(ModifiedCode, "An existent item is modified.");
+    }
+
+    public static class CommonDeleteResponse
+    {
+        public const int DeletedCode = 0;
+        public const int NotExistsCode = 1;
+
+        public static CommonResponse Deleted { get; } = new CommonResponse(DeletedCode, "An existent item is deleted.");
+        public static CommonResponse NotExists { get; } = new CommonResponse(NotExistsCode, "The item does not exist.");
+    }
+}