Improved URL validation

qurl/qurl.go

@@ -29,6 +29,14 @@ func (q *QURL) CheckValid() error {
 		return err
 	}
 
+	if u.Scheme == "" {
+		return fmt.Errorf("URLs must begin with a scheme (e.g. https:)")
+	}
+
+	if u.Host == "" && u.RawQuery == "" && u.RawPath == "" && u.Fragment == "" {
+		return fmt.Errorf("URLs must contain a path, host, query or fragment element")
+	}
+
 	if !u.IsAbs() {
 		return fmt.Errorf("Relative URLs are not allowed")
 	}