[Payment service] Missing attaching Formatter and StreamHandler to application logger

[joaomrcsmartins]

Hi team, I believe I've found a small bug in the payment service logging. I've been using your demo app (thanks btw for creating it and sharing it) as a "guinea pig" of sorts and particularly focused on the logs. When using the load generator with forced errors (bad calls to /api/payment/pay, I looked into the payment service.

There seems to be missing the part where the Formatter is attached to the StreamHandler and the handler to the logger.

robot-shop/payment/payment.py

Lines 151 to 154 in e2cfded

	sh = logging.StreamHandler(sys.stdout)
	sh.setLevel(logging.INFO)
	fmt = logging.Formatter('%(asctime)s - %(name)s - %(levelname)s - %(message)s')
	app.logger.info('Payment gateway {}'.format(PAYMENT_GATEWAY))

It seems to be missing something like this:

sh = logging.StreamHandler(sys.stdout)
sh.setLevel(logging.INFO)
fmt = logging.Formatter('%(asctime)s - %(name)s - %(levelname)s - %(message)s')
sh.setFormatter(fmt)
app.logger.addHandler(sh)

Also, this part should be done before instantiating the RabbitMQ publisher since it passes the app logger as an argument:

robot-shop/payment/payment.py

Lines 147 to 148 in e2cfded

	# RabbitMQ
	publisher = Publisher(app.logger)

Thanks again for the work to have this demo tool publicly open!