+
+ @staticmethod
+ def verify_vat_retval(vat_out, exp_retval=0, err_msg='VAT cmd failed'):
+ """Verify return value of VAT command.
+
+ VAT command JSON output should be object (dict in python) or array. We
+ are looking for something like this: { "retval": 0 }. Verification is
+ skipped if VAT output does not contain return value element or root
+ elemet is array.
+
+ :param vat_out: VAT command output in python representation of JSON.
+ :param exp_retval: Expected return value (default 0).
+ :err_msg: Message to be displayed in case of error (optional).
+ :type vat_out: dict or list
+ :type exp_retval: int
+ :type err_msg: str
+ :raises RuntimeError: If VAT command return value is incorrect.
+ """
+ if type(vat_out) is dict:
+ retval = vat_out.get('retval')
+ if retval is not None:
+ if retval != exp_retval:
+ raise RuntimeError(err_msg)