Module: Djinn::Base

Includes:
Logging, Tonic
Included in:
Djinn, Rails
Defined in:
lib/djinn/base.rb,
lib/djinn/base/dsl.rb,
lib/djinn/base/tonic.rb,
lib/djinn/base/logging.rb,
lib/djinn/base/pid_file.rb

Overview

The base class from which all Djinn spring forth

Defined Under Namespace

Modules: Dsl, Logging, Tonic Classes: PidFile

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods included from Logging

#cyan, #green, #log, #red

Methods included from Tonic

#daemonize

Instance Attribute Details

#config ⇒ Object (readonly)

Returns the value of attribute config.



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# File 'lib/djinn/base.rb', line 15

def config
  @config
end

Instance Method Details

#handle_exit ⇒ Object

Override this with useful exit code if you need to, but remember to call super or call exit yourself, or your Djinn will be immortal. This is truly terrible code, and will be removed soon.



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# File 'lib/djinn/base.rb', line 33

def handle_exit
  __exit! if respond_to?(:__exit!)
  exit(0)
end

#initialize ⇒ Object 



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# File 'lib/djinn/base.rb', line 17

def initialize
  @config = { :__daemonize => true }
end

#perform(config = {}) ⇒ Object

Base implementation does nothing worthwhile, you should override this in your own implementation.



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# File 'lib/djinn/base.rb', line 23

def perform config={}
  while
    log("[#{name}] Djinn is running.. and doing nothing worthwhile.")
    sleep(5)
  end 
end

#restart(config = {}) ⇒ Object

Convenience method, really just calls stop and then start for you :P



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# File 'lib/djinn/base.rb', line 71

def restart config={}
  stop
  start(config)
end

#run(config = {}) {|_self| ... } ⇒ Object

Starts the Djinn in the foreground, which is often useful for testing or other noble pursuits.

Yields:

  • (_self)

Yield Parameters:

  • _self (Djinn::Base) —

    the object that the method was called on



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# File 'lib/djinn/base.rb', line 57

def run config={}, &block
  @config.update(config).update(load_config)
  # @config = (config.empty?) ? load_config : config
  log "Starting #{name} in the foreground.."
  trap('TERM') { handle_exit }
  trap('INT')  { handle_exit }
  yield(self) if block_given?
  (respond_to?(:__start!)) ? __start! : perform(@config)
  # If this process doesn't loop or otherwise breaks out of 
  # the loop we still want to clean up after ourselves
  handle_exit
end

#start(config = {}, &block) ⇒ Object

Starts the Djinn in the background.



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# File 'lib/djinn/base.rb', line 39

def start config={}, &block
  @config.update(config).update(load_config)
  #@config = (config.empty?) ? load_config : config
  log "Starting #{name} in the background.."
  logfile = get_logfile(config)
  daemonize(logfile, get_pidfile(config)) do
    yield(self) if block_given?
    trap('TERM') { handle_exit }
    trap('INT')  { handle_exit }
    (respond_to?(:__start!)) ? __start! : perform(@config)
    # If this process doesn't loop or otherwise breaks out of 
    # the loop we still want to clean up after ourselves
    handle_exit
  end
end

#stop(config = {}) {|_self| ... } ⇒ Object

Stops the Djinn, unless you change the location of the pid file, in which case its all about you and the kill command

Yields:

  • (_self)

Yield Parameters:

  • _self (Djinn::Base) —

    the object that the method was called on



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# File 'lib/djinn/base.rb', line 78

def stop config={}
  @config.update(config).update(load_config)
  # @config = (config.empty?) ? load_config : config
  yield(self) if block_given?
  __stop! if respond_to?(:__stop!)
  pidfile = get_pidfile(@config)
  log 'No such process' and exit unless pidfile.pid
  begin
    log "Sending TERM signal to process #{pidfile.pid}"
    Process.kill("TERM", pidfile.pid)
  rescue
    log 'Could not find process'
  ensure
    pidfile.remove
  end
  
end