Sample setup code of how to keep using the standard logging frontend but using structlog to manage richer logging context

structlog_stdlib_takeover.py

import logging
import sys

import structlog
from pythonjsonlogger import jsonlogger

# Normal standard logging setup
logging.basicConfig(
    format="%(message)s",
    stream=sys.stderr,
    level=logging.INFO
)

# Takeover setup
structlog.configure(
    processors=[
        structlog.stdlib.filter_by_level,
        structlog.stdlib.add_logger_name,
        structlog.stdlib.add_log_level,
        structlog.stdlib.PositionalArgumentsFormatter(),
        structlog.processors.StackInfoRenderer(),
        structlog.processors.format_exc_info,
        structlog.processors.UnicodeDecoder(),
        # Transform event dict into `logging.Logger` method arguments.
        # "event" becomes "msg" and the rest is passed as a dict in
        # "extra". IMPORTANT: This means that the standard library MUST
        # render "extra" for the context to appear in log entries! See
        # warning below.
        structlog.stdlib.render_to_log_kwargs,
    ],
    logger_factory=structlog.stdlib.LoggerFactory(),
    wrapper_class=structlog.stdlib.BoundLogger,
    cache_logger_on_first_use=True,
)

handler = logging.StreamHandler(sys.stdout)
handler.setFormatter(jsonlogger.JsonFormatter())
root_logger = logging.getLogger()
root_logger.handlers = [handler]


# What you get in each module that logs
log = logging.getLogger(__name__)
log.info("Will it log?", extra={"key": "value"})