Show the source of your Rails log messages. Put this file in your config/initializers directory.

detailed_logger.rb

require 'active_support/buffered_logger'

class ActiveSupport::BufferedLogger

  def add(severity, message = nil, progname = nil, &block)
    add_debugging_details(severity)
    @log.add(severity, message, progname, &block)
  end

  private

  EXCLUDE_CALLERS = Gem.paths.path.clone << 'script/rails' << RbConfig::CONFIG['rubylibdir'] << __FILE__

  def add_debugging_details(severity)
    caller_in_app = caller.select do |line|
      EXCLUDE_CALLERS.detect { |gem_path| line.starts_with?(gem_path) }.nil?
    end

    return if caller_in_app.empty?

    @log.add(severity, "Your code in \e[1;33m#{caller_in_app.first.sub(%r(^#{Rails.root}/), '')}\e[0;0m triggered:")
  end

end if Rails.env.development?