large refactor, fixes #2

server/internal/utils/json.go

@@ -0,0 +1,10 @@
+package utils
+
+import "encoding/json"
+
+func Unmarshal(in interface{}, raw []byte, callback func() error) error {
+	if err := json.Unmarshal(raw, &in); err != nil {
+		return err
+	}
+	return callback()
+}