Style Guide

This style guide extends PEP 8 with recommendations that should be followed in this project.

Logging

Use the appropriate log level based on these meanings:

• DEBUG: troubleshooting - not for testing.

• INFO: normal operation - state changes.

• WARNING: might be a problem - inform user.

• ERROR: definitely a problem - inform developer.

• FATAL/CRITICAL: too similar to ERROR - just throw an exception.

Log message with a format string to avoid interpolating variables when the log level is not applicable:

logging.info(
    "Starting %(service)s on port %(port)s",
    {"service": service, "port": port},
)

Testing

• Test the interface, not the implementation.

• Test the messages, not the state.

• Separate dependency tree from runtime tree.

• Only mock types that you own.

• Unit test behavior, not methods.

• We can write the test, but can we live with it?