require 'active_support/core_ext/object/blank'
require 'active_support/deprecation'
require 'logger'
module ActiveSupport
# Wraps any standard Logger class to provide tagging capabilities. Examples:
#
# 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.
class TaggedLogging
def initialize(logger)
@logger = logger
end
def tagged(*tags)
new_tags = push_tags(*tags)
yield self
ensure
pop_tags(new_tags.size)
end
def push_tags(*tags)
tags.flatten.reject(&:blank?).tap do |new_tags|
current_tags.concat new_tags
end
end
def pop_tags(size = 1)
current_tags.pop size
end
def clear_tags!
current_tags.clear
end
def silence(temporary_level = Logger::ERROR, &block)
@logger.silence(temporary_level, &block)
end
deprecate :silence
def add(severity, message = nil, progname = nil, &block)
message = (block_given? ? block.call : progname) if message.nil?
@logger.add(severity, "#{tags_text}#{message}", progname)
end
%w( fatal error warn info debug unknown ).each do |severity|
eval <<-EOM, nil, __FILE__, __LINE__ + 1
def #{severity}(progname = nil, &block)
add(Logger::#{severity.upcase}, nil, progname, &block)
end
EOM
end
def flush
clear_tags!
@logger.flush if @logger.respond_to?(:flush)
end
def method_missing(method, *args)
@logger.send(method, *args)
end
private
def tags_text
tags = current_tags
if tags.any?
tags.collect { |tag| "[#{tag}] " }.join
end
end
def current_tags
Thread.current[:activesupport_tagged_logging_tags] ||= []
end
end
end