root/lang/perl/Data-Valve/trunk/lib/Data/Valve/BucketStore/WithKeyedMutex.pm @ 15788

# $Id$

package Data::Valve::BucketStore::WithKeyedMutex;
use Moose::Role;
use Moose::Util::TypeConstraints;

use KeyedMutex;

class_type 'KeyedMutex';

coerce 'KeyedMutex'
    => from 'HashRef'
        => via {
            my $h = $_;
            KeyedMutex->new($h->{args});
        }
;

has 'mutex' => (
    is => 'rw',
    isa => 'KeyedMutex',
    coerce => 1,
);

no Moose;

sub BUILD {
    my $self = shift;

    # if no keyedmutex was provided explicitly, we attempt to create one
    # however, if the creation of this object fails, well, we can go
    # without it in degraded mode
    if ( ! $self->mutex ) {
        my $mutex = eval {KeyedMutex->new };
        if ($mutex) {
            $self->mutex($mutex);
        } else {
            warn $@;
        }
    }
}

sub lock {
    my ($self, $key) = @_;

    my $mutex = $self->mutex;
    return 1 unless $mutex;
    my $rv = eval { $mutex->lock($key, 1) };
    # if in case an error has been reported, we should ditch the mutex,
    # cause it will keep giving errors (or worse yet, crash)
    if ($@) {
        $self->mutex(undef);
    }
    return $rv;
}

1;