not found page

internal/server/response/error.go

@@ -14,6 +14,7 @@ type (
 		err    error
 		msg    string
 		status int
+		html   []byte
 	}
 )
 
@@ -77,6 +78,11 @@ func (e ErrorResponse) Wrap(err error) ErrorResponse {
 	return e
 }
 
+func (e ErrorResponse) HTML(h []byte) ErrorResponse {
+	e.html = h
+	return e
+}
+
 // error implementation
 
 func (e ErrorResponse) Error() string {
@@ -130,6 +136,19 @@ func (e ErrorResponse) GetMsg() (string, bool) {
 	return "", false
 }
 
+func (e ErrorResponse) GetHTML() ([]byte, bool) {
+	if len(e.html) != 0 {
+		return e.html, true
+	}
+
+	ce, ok := GetError(e.err)
+	if ok {
+		return ce.GetHTML()
+	}
+
+	return nil, false
+}
+
 func GetError(err error) (e ErrorResponse, ok bool) {
 	ok = errors.As(err, &e)
 	return e, ok