ActiveSupport::TaggedLogging

Wraps any standard Logger object to provide tagging capabilities.

logger = ActiveSupport::TaggedLogging.new(Logger.new(STDOUT))
logger.tagged('BCX') { logger.info 'Stuff' }                            # Logs "[BCX] Stuff"
logger.tagged('BCX', "Jason") { logger.info 'Stuff' }                   # Logs "[BCX] [Jason] Stuff"
logger.tagged('BCX') { logger.tagged('Jason') { logger.info 'Stuff' } } # Logs "[BCX] [Jason] Stuff"

This is used by the default Rails.logger as configured by Railties to make it easy to stamp log lines with subdomains, request ids, and anything else to aid debugging of multi-user production applications.