add unsupported media type for mime type checking

errs/errs.go

@@ -153,6 +153,7 @@ const (
 	// For Unauthorized errors, the response body should be empty.
 	// The error is logged and http.StatusForbidden (403) is sent.
 	Unauthorized
+	UnsupportedMediaType // Unsupported Media Type
 )
 
 func (k Kind) String() string {
@@ -185,8 +186,11 @@ func (k Kind) String() string {
 		return "unauthenticated request"
 	case Unauthorized:
 		return "unauthorized request"
+	case UnsupportedMediaType:
+		return "unsupported media type"
+	default:
+		return "unknown error kind"
 	}
-	return "unknown error kind"
 }
 
 // E builds an error value from its arguments.

errs/httperrors.go

@@ -264,6 +264,8 @@ func httpErrorStatusCode(k Kind) int {
 	switch k {
 	case Invalid, Exist, NotExist, Private, BrokenLink, Validation, InvalidRequest:
 		return http.StatusBadRequest
+	case UnsupportedMediaType:
+		return http.StatusUnsupportedMediaType
 	// the zero value of Kind is Other, so if no Kind is present
 	// in the error, Other is used. Errors should always have a
 	// Kind set, otherwise, a 500 will be returned and no