code: protected function getContextMessage()
      {
          $context = ArrayHelper::filter($GLOBALS, $this->logVars);
          foreach ($this->maskVars as $var) {
              if (ArrayHelper::getValue($context, $var) !== null) {
                  ArrayHelper::setValue($context, $var, '***');
              }
          }
          $result = [];
          foreach ($context as $key => $value) {
              $result[] = "\${$key} = " . VarDumper::dumpAsString($value);
          }
  
          return implode("\n\n", $result);
      }
docs: Generates the context information to be logged.
  The default implementation will dump user information, system variables, etc.
  @return string the context information. If an empty string, it means no context information.