Using logging in multiple modules

python

logging

configuration

best-practices

byAnton Shumikhin·Oct 28, 2024

Centralize logging by setting up a single logging configuration at your program's starting point. Apply the logging.getLogger(__name__) method within each module to maintain consistent and easily-traceable log output.

# Define your logging configuration once at the entry point of your program
import logging
# It's like setting the stage before the drama (your code execution) unfolds
logging.basicConfig(format='%(asctime)s - %(module)s - %(levelname)s: %(message)s', level=logging.INFO)

# Then, in all other modules simply get a logger specific to that module
logger = logging.getLogger(__name__)

# Now, pour your heart out; tell the logger what it needs to know
logger.info("This info is being tracked all the way from the module where I was born!")

Each module gets its own logger when getLogger(__name__) is invoked, linking logs back to their respective modules. This streamlines the debugging process like a well-oiled machine.

Centralized logging configuration

The inheritance factor and handling responsibilities

A centralized configuration is like the code sheriff, maintaining law and order (quality and consistency) and adjusting log levels and formats across all your modules.

Pythonic package logging configuration

For package-wide logging apply root logger configuration in the package's __init__.py. It ensures a standard logging setup across all submodules.

Customization is the spice of logging

basicConfig makes sense for simpler applications, but for King Kongs of complexity, go for fileConfig or dictConfig.

Recyclable logging configuration

Keep the configuration separate in logging.conf or a dictionary (JSON/YAML). You can change log settings without performing open heart surgery on your code.

Advanced logging strategies

Singleton pattern in logging configuration

Use a singleton pattern for your logging configuration. It's like being the only copy of a rare book – there is one and only one instance, ensuring uniformity.

Propagate flag

Understand logger.propagate. When true, log entries from child loggers bubble up to the root logger. Like diligent kids reporting to their parent.

Well-structured logging messages

Improve log readability using custom log formats with relevant contextual information. Because the who, what, and where makes a log entry a juicy detective story!

Logging efficiency

Optimize logging in high-performance environments, using appropriate log levels, and avoiding complex calculations in hot code paths. It's like removing speed bumps from a racing track!

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