NAME

Test::SharedObject - Data sharing in multi process.

SYNOPSIS

use strict;
use warnings;

use Test::More tests => 2;
use Test::SharedFork;
use Test::SharedObject;

my $shared = Test::SharedObject->new(0);
is $shared->get, 0;

my $pid = fork;
die $! unless defined $pid;
if ($pid == 0) {# child
    $shared->txn(sub {
        my $counter = shift;
        $counter++;
        return $counter;
    });
    exit;
}
wait;

is $shared->get, 1;

DESCRIPTION

Test::SharedObject provides atomic data operation between multiple process.

METHODS

• my $shared = Test::SharedObject->new($value)

  Creates a new Test::SharedObject instance. And set $value as initial value.

  Internally, Creates temporary file, and serialize $value by Storable, and save.

• $shared->txn(\&coderef)

  Provides atomic data operation between multiple process in \&coderef. Set shared value as first arguments in \&coderef, and return value as new shared value.

  Internally:

  • Lock temporary file.
  • Read shared value.
  • Executes \&coderef. (Set shared value as first arguments)
  • Write return value as shared value.
  • Unlock temporary file.

  Good Example:

  $shared->txn(sub {
      my $counter = shift;
      $counter++; # atomic!!
      return $counter;
  });
  

  Bad Example:

  my $counter;
  $shared->txn(sub {
      $counter = shift;
  });
  $counter++; # *NOT* atomic!!
  $shared->txn(sub {
      return $counter;
  });
  

• $shared->set($value)

  Set $value as shared value. The syntactic sugar for $shared->txn().

• my $value = $shared->get()

  Get shared value. The syntactic sugar for $shared->txn().

LICENSE

Copyright (C) karupanerura.

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

AUTHOR

karupanerura karupa@cpan.org