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

Well when you've got a lot of traffic running in debug or info mode, the logs aren't readable anyway, with or without newlines. But in case of debug mode in development when you've got separate requests in your log, it's really hard to read without the new lines...

Ahh, that makes sense. I've updated to include a newline before the PID if the logged message starts with a newline. :)

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.