Rails 3 logs with severity and PIDs

better_logger.rb

# You must require this file in application.rb, above the Application
# definition, for this to work. For example:
#
#   # Syslog-like Rails logs
#   if Rails.env.production?
#     require File.expand_path('../../lib/better_logger', __FILE__)
#   end
#
#   module MyApp
#     class Application < Rails::Application

require 'active_support/buffered_logger'

class BetterLogger < ActiveSupport::BufferedLogger

  SEVERITIES = Severity.constants.sort_by{|c| Severity.const_get(c) }

  def add(severity, message = nil, progname = nil, &block)
    return if @level > severity
    message = (message || (block && block.call) || progname).to_s
    # Prepend pid and severity to the written message
    log = "[%s] %-5.5s %s" % [$$, SEVERITIES[severity], message.gsub(/^\n+/, '')]
    # If a newline is necessary then create a new message ending with a newline.
    log << "\n" unless log[-1] == ?\n
    buffer << log
    auto_flush
    message
  end

  class Railtie < ::Rails::Railtie
    # overwrite Rails' initializer to set up our own instead
    initializer :initialize_logger do |app|
      Rails.logger = begin
        logger = BetterLogger.new(app.config.paths.log.to_a.first)
        level_name = app.config.log_level.to_s.upcase
        logger.level = ActiveSupport::BufferedLogger.const_get(level_name)
        logger.auto_flushing = false if Rails.env.production?
        logger
      end
      ActiveSupport::Dependencies.logger = Rails.logger

      # cache has no callback of its own, but is set before this callback
      ActiveSupport.on_load(:before_initialize) do
        Rails.cache.logger = Rails.logger
      end
      ActiveSupport.on_load(:active_record) do
        ActiveRecord::Base.logger = Rails.logger
      end
      ActiveSupport.on_load(:action_controller) do
        ActionController::Base.logger = Rails.logger
      end
      ActiveSupport.on_load(:action_mailer) do
        ActionMailer::Base.logger = Rails.logger
      end
    end

  end

end

Couldnt you eliminate a bunch of the code by just overriding the add() method in an initializer?

Something like:

class Railtie < ::Rails::Railtie
    initializer "swap in PidLogger" do
      module ActiveSupport
         class BufferedLogger
            def add(severity, message = nil, progname = nil, &block)
               return if @level > severity
               message = (message || (block && block.call) || progname).to_s
               # Insert a newline before the log line if there was one in the first place.
               log = (message[0] == ?\n) ? "\n" : ""
               # Prepend pid and severity to the written message
               log << "[#{$$}] #{SEVERITIES[severity]} #{message.gsub(/^\n+/, '')}"
               # If a newline is necessary then end with a newline.
               log << "\n" unless log[-1] == ?\n
               buffer << log
              auto_flush
              log
            end
        end
    end
 end

Probably, but I wasn't comfortable monkeypatching BufferedLogger.

Hi man,

I forked your code, but instead of recreating everything that is done in the method and the initializer I just extend the actual logger object.
Pretty neat solution.