Daemonizer: Simple framework for creating daemons with Ruby
====================================

**Homepage**:     [http://daemonizer.org](http://daemonizer.org)   
**Git**:          [http://github.com/glebpom/daemonizer](http://github.com/glebpom/daemonizer)   
**Author**:       Gleb Pomykalov    
**Copyright**:    2010    
**License**:      MIT License    
**Status**:       alpha    

Synopsis
--------

Daemonizer is a simple ruby framework to create custom daemons. It is fully 
compatible with EventMachine, Rails and any other Ruby frameworks. Two workers
type supported - forked and threaded.


Feature List
------------
                                                                              
**1. Demfile (similar to Gemfile, Rakefile)** as a configuration file. It is 
possible to describe different background pools there.

**2. Two engines**: :thread and :fork. (thread is currently broken)
                                                                              
**3. Monitoring**: If child is found dead it will be immediately 
restored
                                                                              
**4. Logging** (via [http://log4r.rubyforge.org/](log4r))

Installing
----------

To install Daemonizer, use the following command:

    $ gem install daemonizer
    
(Add `sudo` if you're installing under a POSIX system as root)                                                                              

Usage
-----

**Demfile example:**

    engine :fork 
    workers 2

    pool :daemonizer do
      workers 4
      poll_period 5
      log_file "log/daemonizer.log" #relative to Demfile
  
      before_init do |logger, block|
        block.call
      end
  
      after_init do |logger, worker_id, workers_count|
        logger.info "Started #{worker_id} from #{workers_count}"
    
        exit = false
    
        stop = proc {
          exit = true
        }

        trap('TERM', stop)
        trap('INT', stop)
        trap('EXIT', stop)
    
        loop do
          break if exit
          logger.info "Ping #{worker_id}"
          sleep 10
        end
    
        true
      end
    end

    pool :new_daemonizer do
      workers 4
      poll_period 5
      log_file "log/daemonizer.log" #relative to Demfile

      handler ::MyBackgroundSolution::DaemonizerHandler
  
      set_option :queue, lambda { |worker_id, worker_count| "queue_#{worker_id}"}
    end


**Handler example**

    module MyBackgroundSolution
      class DaemonizerHandler < Daemonizer::Handler
        def before_init(block)
          require File.join(Daemonizer.root, '/config/environment') #Require rails
          require 'my_background_solution/worker' #Require our code
          super #now we are ready to fork
        end

        def after_init 
          #we are in worker process
          logger.info "Starting cycle. We are number #{worker_id} from #{workers_count}"
          logger.info "Options - #{option(:queue)}" #We can get option :queue, which is set with set_option in pool configuration
          worker = Worker.new
          worker.run
          logger.info "Ending cycle"
        end
      end
    end
    
Who are the authors
-------------------

This gem has been created in qik.com for our internal use and then 
the sources were opened for other people to use. All the code in this package 
has been developed by Gleb Pomykalov, and is based on 
[http://github.com/kovyrin/loops](loops) code written by 
Alexey Kovyrin. The gem is released under the MIT license. For more details, 
see the LICENSE file.