NAME

Net::Sentinel - Manages a given condition and actions to take when the condition is true

SYNOPSIS

The Net::Sentinel object requires a name describing it, a directory to operated from, a condition to execute to check if actions need to be ran and a list of actions to run should the condition return true.

# A sub to check every second. A return value of 1 indiciates the actions need
# to be ran. A return value of 0 indicates that the condition is not met. A log
# message is required to be returned by the condition explaing the result
sub some_condition {
   if ( 1 == 1 ) {
       return ( 1, "tripped" );
   }
   else {
       return ( 0, "all good" );
   }
}

# A sub to passed to Net::Sentinel::Action to be ran when the condtion is true
sub some_action {
   print "I was ran.\n";
}

# The sentinel object that manages the condition and actions
my $sentinel = Net::Sentinel->new(
    'name'      => 'the-watcher',
    'base-dir'  => '/var/sentinel/',
    'condition' => \&some_condition,
    'actions'   => [
        Net::Sentinel::Action->new(
            'name'  => 'the-action',
            'spawn' => \&some_action,
            'type'  => ACTION,
        ),
    ],
);

# Turn the sentinel on
$sentinel->start;

DESCRIPTION

This class defines the Net::Sentinel which executes the supplied condition and executes all supplied actions when the condition is true

METHODS

new( %params ) (constructor)

Creates a new Sentinel.

Required values are name (scalar), base-dir (scalar), condition (coderef), actions (arrayref of Net::Sentinel::Actions).

Returns: New instance of Sentinel

start

Daemonizes the Sentinel.

Returns: exit

stop

Stops the daemon.

Returns: exit

status

Prints the current state of the Sentinel.

Returns: exit

set_name( $name )

Sets the name of the Sentinel

Returns: undef

get_name

Gets the name of the Sentinel

Returns: name (scalar)

set_once

Sets the once flag on the Sentinel. The Sentinel will only trigger once and exit on recovery.

Returns: undef

get_once

Gets the once flag

Returns: once (scalar)

set_base_dir( $base_dir )

Sets the director from which the Sentinel will operate from

Returns: undef

get_base_dir

Gets the directory where the Sentinel is operating from

Returns: base_dir (scalar)

set_condition( \&condition )

Sets the coderef the Sentinel will execute every iteration to check if true. If the condition is true the Sentinel will execute all Net::Sentinel::Actions defined.

Returns: undef

get_condition

Gets the condition coderef to execute.

Returns: condition (coderef)

set_condition_delay( $recovery_seconds )

Sets the delay (in seconds) the Sentinel should wait before executing the condition. Default is to check the condition every second

Returns: undef

get_condition_delay

Gets the congition delay seconds

Returns: condition_delay (scalar)

set_actions( \@actions )

Sets the Actions the Sentinel will execute when the condition is true

Returns: undef

get_actions

Returns the Actions that Sentinel will execute when the condition is true

Returns: actions (arrayref)

set_recovery( \@recovery_actions )

Sets the Actions to run on recovery when the condition returns to false

Returns: undef

get_recovery

Returns the Actions to run on recovery

Returns: recovery (arrayref)

set_recovery_time( $recovery_delay )

Sets the amount of time in seconds the Sentinel should wait after condition returns false before executing recovery actions.

Returns: undef

get_recovery_time

Gets the recovery time delay.

Returns: recovery_time (scalar)

set_timeout( $socket_timeout )

Sets the timeout on the UNIX socket the Sentinel uses

Returns: undef

get_timeout

Gets the UNIX socket timeout

Returns: timeout (scalar)