NAME

ControlFreak::Proxy - Delegate some control to an intermediary process.

DESCRIPTION

There are some cases where you want some services managed in a special way, and it makes no sense to implement this in ControlFreak itself.

Indeed, one design trait of ControlFreak is its absolute simplicity, we don't want to clutter it with features that are only rarely used or that could make the controller unstable.

One example of that is Memory Sharing. If you have 20 application processes running on one machine all having the same code running, there is a memory benefit into making sure the app is loaded in the parent process of all these applications. Indeed, it would allow all children to initially share parent code and thus potentially reduce the memory footprint of the application by quite a while, maybe. But, it's out of question for the controller to load that code in its own memory. A better solution is to use a ControlFreak::Proxy separate process that will:

• load the application code once and for all

• take commands from the main controller (over pipes)

• fork children when instructed, that exec some user defined commands

SYNOPSIS

  $proxy = ControlFreak::Proxy->new(
      ctrl => $ctrl,
      cmd  => '/usr/bin/cfk-share-mem-proxy.pl --preload Some::Module',

  );
  $proxy->add_service($svc);
  $proxy->destroy_service($svc);
  $proxy->run;
  $proxy->start_service($svc);
  $proxy->stop_service($svc);
  @list = $proxy->services;
  $proxy->shutdown;
  $proxy->is_running;

METHODS

new(%param)

status_as_text

Returns the status of the proxy, including its eventual pid in one line of text, where the following fields are seperated with tabs:

• name

• status ('up' or 'down')

• pid, if proxy is up

services

Returns a list of ControlFreak::Service objects related to the proxy.

add_service($svc)

Declares a service under the control of the proxy.

start_service

Given a ControlFreak::Service, check that it is effectively under the control of a ControlFreak::Proxy object and contact the later to instruct it to start the service on our behalf.

add_env($key => $value)

Adds an environment key, value pair to the proxy

clear_env()

Resets proxy environment to empty.

run

Runs the proxy command.

shutdown

Quits the proxy (and consequently stops all related services).

has_stopped

Called when the proxy has exited. It performs a number of cleaning tasks.