/ 
Svsh-1.002000
River stage zero No dependents
/ Svsh

NAME

Svsh - Process supervision shell for daemontools/perp/s6/runit (base class)

SYNOPSIS

package Svsh::SomeSupervisor;

use Moo;
use namespace::clean;

with 'Svsh';

# implement required methods

DESCRIPTION

svsh is a shell for process supervision suites of the daemontools family, including perp, s6 and runit. Refer to svsh for documentation of the shell itself. This file documents the base class for Svsh adapter classes.

ATTRIBUTES

basedir

Required, Read-Only.

The base directory from which the process supervisor is managing services.

bindir

Read-Only.

The directory where the process supervisor's tools are located. Any call to the supervisor's tools will be prefixed with this path if provided. For usage in case the tools are not in the running user's PATH environment variable.

collapse

Read-Write.

A boolean indicating whether the collapse option should be enabled.

statuses

Read-Only.

A hash-ref of services and their statuses (this is automatically populated by the respective status() method in the adapter classes. For every service, a hash-ref with status, duration and pid keys should exist.

REQUIRED METHODS

status()

Finds all services managed by the supervisor, and populates the statuses attribute.

start( @services )

Starts a list of services if they are down.

stop( @services )

Stops a list of services (should not restart them).

restart( @services )

Stops and starts a list of services. Generally, this is implemented with a QUIT signal to the services, but check with the specific adapter class.

signal( $signal, @services )

Sends UNIX signal to a list of services.

fg( $service )

Finds the log file to which a service is writing, and displays it on screen with the tail -f command.

WANTED METHODS

These methods are not required by adapter classes. If they are not implemented, they will be unavailable in the shell.

rescan()

Causes the supervisor to rescan the service directory to find new or removed services.

terminate()

Terminates the supervisor. Should also terminate all running services.

METHODS

run_cmd( $cmd, [ @args ] )

Runs a shell command with zero or more arguments and returns its output. If the bindir attribute is set, and the $cmd is one of the supervision suite's library of tools, $cmd will be prefixed with bindir.

find_logfile( $pid )

Finds the log file into which a logging program is currently writing to. $pid is the process ID of the logging program. Currently, tinylog, s6-log, svlogd and multilog are supported.

Returns undef if the file is not found.

BUGS AND LIMITATIONS

No bugs have been reported.

Please report any bugs or feature requests to bug-Svsh@rt.cpan.org, or through the web interface at http://rt.cpan.org/NoAuth/ReportBug.html?Queue=Svsh.

SUPPORT

You can find documentation for this module with the perldoc command.

perldoc Svsh

You can also look for information at:

AUTHOR

Ido Perlmuter <ido at ido50 dot net>

LICENSE AND COPYRIGHT

Copyright (c) 2015, Ido Perlmuter ido at ido50 dot net.

This module is free software; you can redistribute it and/or modify it under the same terms as Perl itself, either version 5.8.1 or any later version. See perlartistic and perlgpl.

The full text of the license can be found in the LICENSE file included with this module.

DISCLAIMER OF WARRANTY

BECAUSE THIS SOFTWARE IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY FOR THE SOFTWARE, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE SOFTWARE "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE SOFTWARE IS WITH YOU. SHOULD THE SOFTWARE PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, REPAIR, OR CORRECTION.

IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR REDISTRIBUTE THE SOFTWARE AS PERMITTED BY THE ABOVE LICENCE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE THE SOFTWARE (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A FAILURE OF THE SOFTWARE TO OPERATE WITH ANY OTHER SOFTWARE), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.