Insecure Design

Make sure your systems are observable: your running code should issue logging statements and logs should be viewable at run time. You should be able to observe the type and volume of traffic hitting your servers and how much of your available bandwidth is being used.

Observability

   import logging

# Will print "WARNING:root:Watch out!" to the console.
logging.warning("Warning message")

# Configure the logs to include the time and date.
logging.basicConfig(
  format = "%(asctime)s %(levelname)s:%(message)s",
  level  = logging.DEBUG,
  force  = True
)

# Will prefix a timestamp with format "2010-12-12 11:41:42,612" to the log.
logging.info("Info message") 