Merge pull request #99 from cybozu-go/issue-98

issue-98: Fixed determination of whether root user exists or not

cmd/moco-agent/cmd/root.go

@@ -259,7 +259,7 @@ func initializeMySQLForMOCO(ctx context.Context, socketPath string, logger logr.
  if err == nil {
  break
  }
- if server.IsAccessDenied(err) {
+ if server.UserNotExists(err) {
  // There is no passwordless 'root'@'localhost' account.
  // It means the initialization has been completed.
  return nil

server/connect.go

@@ -53,9 +53,14 @@ func GetMySQLConnLocalSocket(user, password, socket string) (*sqlx.DB, error) {
  return db, nil
 }
 
-func IsAccessDenied(err error) bool {
+func UserNotExists(err error) bool {
+ // For security reason, error messages are randomly output when a user does not exist.
+ // https://github.com/mysql/mysql-server/commit/b40001faf6229dca668c9d03ba75c451f999c9f5
+ // This function assumes the user does not exist when the following message is output:
+ // ERROR 1045 (28000): Access denied for user 'root'@'localhost' (using password: NO)
+ // ERROR 1524 (HY000): Plugin 'mysql_native_password' is not loaded
  var merr *mysql.MySQLError
- if errors.As(err, &merr) && merr.Number == 1045 {
+ if errors.As(err, &merr) && (merr.Number == 1045 || merr.Number == 1524) {
  return true
  }