POE::Component::Supervisor - Erlang-inspired babysitting
use POE; use POE::Component::Supervisor; POE::Component::Supervisor->new( children => [ POE::Component::Supervisor::Supervised::Proc->new( ... ), # monitor UNIX procs POE::Component::Supervisor::Supervised::Session->new( ... ), # monitor POE sessions ], );
This is a port of the Erlang process supervisor (http://www.erlang.org/doc/design_principles/sup_princ.html).
This will monitor instances of children, restarting them as necessary should they exit.
Restart throttling is not yet implemented but planned for a future version.
A supervisor has any number of supervised child descriptors, which in turn instantiate handles for each spawned instance of the child.
Supervised children are essential object factories for handles. They spawn new instances of the child they describe by instantiating handles.
A handle will do the actual management of the child, sending events to the supervisor when the child is terminated, and also facilitate explicit termination of the child's instance.
Based on its
restart_policy the supervisor may order other handles to also stop, and ask various child descriptors to respawn certain children.
POE REFERENCE COUNTING
When no more children are being supervised the POE reference count for the supervisor's session will go down to zero. If no
alias is set up then the session will close. If an
alias is set and no other sessions are doing anything the session will also close. See POE, and MooseX::POE::Aliased.
This defaults to
undef, unlike the role, so that a supervisor session will close automatically once it has no more children to supervise.
Changes the default to true, to allow usage of an already configured Log::Dispatch::Config setup.
This is one of
If the POE::Component::Supervisor::Supervised object describing the child deems the child should be restarted, then the value of this attribute controls which other children to also restart.
onedenotes that only the child which died will be restarted.
restwill cause all the children appearing after the child which died in the children array to be restarted, but not the children preceding it.
allwill restart all the children.
This is the array of children being supervised.
It is a required argument.
Note that the array reference will be modified if new children are introduced and when children are removed (even during normal shutdown), so pass in a copy of an array if this is a problem for you.
The order of the children matters, see
- new %args
- start @children
Spawn and supervise the children described by the descriptors in @children.
- stop [ @children ]
Stop the specified children.
If no arguments are provided all the children are stopped.
- should_restart_child $child, %args
$childby calling "should_restart" in POE::Component::Supervisor::Supervised.
Currently always returns false. In the future restart throttling will be implemented using this method.
trueis returned an error will be thrown by the supervisor.
Stevan Little <firstname.lastname@example.org>
Yuval Kogman <email@example.com<gt>
Copyright (c) 2008, 2010 Infinity Interactive, Yuval Kogman. All rights reserved This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.