A Resource must be a struct that implements the Resource interface

resource.go

@@ -16,7 +16,7 @@ type Resource interface {
 }
 
 // GetResource unmarshal the request body and return the resource
-func GetResource(req *http.Request, resource interface{}) {
+func GetResource(req *http.Request, resource Resource) {
 	body, _ := ioutil.ReadAll(req.Body)
 
 	if IsJSONAPI(req) {