Supervisor - A process to supervisor other processes
A supervisor is a process that controls other processes. One of the most well known ones is /sbin/init, which is ran by the *nix kernel to set up the initial environment. Init is also used to monitor and keep processes running when they exit.
While this supervisor is no replacement for init, it does share some of those characteristics. A daemon that runs in the background, monitoring a series of processes, restarting them should they exit. It also has a command line utility to start, stop, stat and reload a monitored process.
To do this, the supervisor is broken up into three parts. Each part is represented by an object. Each object is a based on a POE session and the events that they can respond too.
One part has the concept of a managed process. It contains the neccessary methods and events to control a process. When a process exits, an event is generated and sent to the supervisor.
A second part has the ability to allow access from external utilities to the managed processes. This allows utilities to start, stop, stat and/or reload managed processes.
And thirdly, there is a part that controls this interaction between the managed processes, external events and the neccesity of keeping those processes running.
So to do all this, the three parts are broken out over several modules.
Basic functionality is provided by these modules.
Supervisor::Base - sets version number and provides documentation Supervisor::Class - defines the constants and common utilty functions Supervisor::Constants - provides uniform constants for the environment Supervisor::Log - provides a common logging interface Supervisor::Session - provides a base POE session Supervisor::Utils - provides common utility functions
Process management is provided by these modules:
Supervisor::Process - base module for a managed process Supervidor::ProcessFactory - loads multiple processes from a config file
The external interface is provided by these modules:
Supervisor::RPC::Server - provide an interface to the external world Supervisor::RPC::Client - used by external world to communcicate
The internal interface between processes and the external world:
Supervisor::Controller - controls the processes and external access
These modules all combined togther make a supervisor that will keep a process running and allow control of that process from external utilties.
Supervisor::Base Supervisor::Class Supervisor::Constants Supervisor::Controller Supervisor::Log Supervisor::Process Supervisor::ProcessFactory Supervisor::Session Supervisor::Utils Supervisor::RPC::Server Supervisor::RPC::Client
Kevin L. Esteb, <kesteb@wsipc.org>
Copyright (C) 2009 by Kevin L. Esteb
This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself, either Perl version 5.8.5 or, at your option, any later version of Perl 5 you may have available.
To install Supervisor, copy and paste the appropriate command in to your terminal.
cpanm
cpanm Supervisor
CPAN shell
perl -MCPAN -e shell install Supervisor
For more information on module installation, please visit the detailed CPAN module installation guide.