Embedded Linux Development Using Yocto Project Cookbook - Second Edition

Adding logging to recipes

BitBake recipes accept either Bash or Python code. Python logging is done through the bb class and uses the standard logging Python library module. It has the following components:

• bb.plain: This uses logger.plain. It can be used for debugging, but should not be committed to the source.
• bb.note: This uses logger.info.
• bb.warn: This uses logger.warn.
• bb.error: This uses logger.error.
• bb.fatal: This uses logger.critical and exits BitBake.
• bb.debug: This should be passed a log level as the first argument and uses logger.debug.

To print debug output from Bash in our recipes, we need to use the logging class by executing:

inherit logging  

The logging class is inherited by default by all recipes containing base.bbclass ...