def wait_for_service(self, app_name, port, expected_output=None, timeout=<NUM_LIT:100>):
logger.info('<STR_LIT>')<EOL>try:<EOL><INDENT>Probe(timeout=timeout, pause=<NUM_LIT:10>, fnc=self.request_service, app_name=app_name,<EOL>port=port, expected_output=expected_output, expected_retval=True).run()<EOL><DEDENT>except ProbeTimeout:<EOL><INDENT>logger.warning("<STR_LIT>")<EOL>raise ConuException("<STR_LIT>")<EOL><DEDENT>
Block until service is not ready to accept requests,
raises an exc ProbeTimeout if timeout is reached
:param app_name: str, name of the app
:param port: str or int, port of the service
:param expected_output: If not None method will check output returned from request
       and try to find matching string.
:param timeout: int or float (seconds), time to wait for pod to run
:return: None