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.

Methods

Class Public methods

new(logger)

# File activesupport/lib/active_support/tagged_logging.rb, line 63
def self.new(logger)
  logger = logger.dup

  if logger.formatter
    logger.formatter = logger.formatter.dup
  else
    # Ensure we set a default formatter so we aren't extending nil!
    logger.formatter = ActiveSupport::Logger::SimpleFormatter.new
  end

  logger.formatter.extend Formatter
  logger.extend(self)
end

Instance Public methods

flush()

# File activesupport/lib/active_support/tagged_logging.rb, line 83
def flush
  clear_tags!
  super if defined?(super)
end

tagged(*tags)

# File activesupport/lib/active_support/tagged_logging.rb, line 79
def tagged(*tags)
  formatter.tagged(*tags) { yield self }
end