Filter hasAllowedScheme(String attribute, Iterable<String> schemes)

Source

static Filter hasAllowedScheme(String attribute, Iterable<String> schemes) =>
    (t, o) {
      var uri = o[attribute];
      if (uri == null || !isValid(uri)) {
        return false;
      }
      var scheme = Uri.parse(uri).scheme;
      return scheme.isEmpty || schemes.contains(scheme);
    };