--- /dev/null
+<?php
+
+namespace seekat\API\ContentType;
+
+use http\Message\Body;
+
+interface Handler {
+ /**
+ * List handled types
+ * @return array
+ */
+ function types() : array;
+
+ /**
+ * Decode HTTP message body
+ * @param Body $body
+ * @return mixed
+ */
+ function decode(Body $body);
+
+ /**
+ * Encode HTTP message body
+ * @param $data
+ * @return Body
+ */
+ function encode($data) : Body;
+}