NAME

Data::WeightedRoundRobin - Serve data in a Weighted RoundRobin manner.

SYNOPSIS

use Data::WeightedRoundRobin;
my $dwr = Data::WeightedRoundRobin->new([
    qw/foo bar/,
    { value => 'baz', weight => 50 },
    { key => 'hoge', value => [qw/fuga piyo/], weight => 120 },
]);
$dwr->next; # 'foo' : 'bar' : 'baz' : [qw/fuga piyo/] = 100 : 100 : 50 : 120

DESCRIPTION

Data::WeightedRoundRobin is a Serve data in a Weighted RoundRobin manner.

METHODS

new([$list:ARRAYREF, $option:HASHREF])

Creates a Data::WeightedRoundRobin instance.

$dwr = Data::WeightedRoundRobin->new();               # empty rr data
$dwr = Data::WeightedRoundRobin->new([qw/foo bar/]);  # foo : bar = 100 : 100

# foo : bar : baz : qux = 100 : 100 : 120 : 50 :
$dwr = Data::WeightedRoundRobin->new([
    'foo',
    { value => 'bar' },
    { value => 'baz', weight => 120 },
    { key => 'qux', value => [qw/q u x/], weight => 50 },
    \{ foo => 'bar' },
]);

Sets default_weight option, DEFAULT is $Data::WeightedRoundRobin::DEFAULT_WEIGHT.

# foo : bar : baz = 0.3 : 0.7 : 1
$dwr = Data::WeightedRoundRobin->new([
    { value => 'foo', weight => 0.3 },
    { value => 'bar', weight => 0.7 },
    { value => 'baz' },
], { default_weight => 1 });

next()

Fetch a data.

 my $dwr = Data::WeightedRoundRobin->new([
     qw/foo bar/],
     { value => 'baz', weight => 50 },
 );
 
 # Infinite loop
 while (my $data = $dwr->next) {
     say $data; # foo : bar : baz = 100 : 100 : 50 
 }

set($list:ARRAYREF)

Sets datum.

$drw->set([
    { value => 'foo', weight => 100 },
    { value => 'bar', weight => 50  },
]);

You can specify the following data.

[qw/foo/]                           # eq [ { key => 'foo', value => 'foo', weight => 100 } ]
[{ value => 'foo' }]                # eq [ { key => 'foo', value => 'foo', weight => 100 } ]
[{ key => 'foo', value => 'foo' }]  # eq [ { key => 'foo', value => 'foo', weight => 100 } ] 

add($value:SCALAR || $value:HASHREF)

Add a value. You can add NOT already value. Returned value is 1 or 0, but if error is undef.

use Test::More;
my $dwr = Data::WeightedRoundRobin->new([qw/foo bar/]);
is $dwr->add('baz'), 1, 'added baz';
is $dwr->add('foo'), 0, 'foo is exists';
is $dwr->add({ value => 'hoge', weight => 80 }), 1, 'added hoge with weight 80';
is $dwr->add(), undef, 'error';

replace($value:SCALAR || $value::HASHREF)

Replace a value. Returned value is 1 or 0, but if error is undef.

use Test::More;
my $dwr = Data::WeightedRoundRobin->new([qw/foo/, { value => 'bar', weight => 50 }]);
is $dwr->replace('bar'), 1, 'replaced bar to default weight (50 -> 100)';
is $dwr->replace('hoge'), 0, 'hoge is not found';
is $dwr->replace({ value => 'foo', weight => 80 }), 1, 'replaced foo with weight 80';
is $dwr->replace(), undef, 'error';

remove($value:SCALAR)

Remove a value. Returned value is 1 or 0, but if error is undef.

use Test::More;
my $dwr = Data::WeightedRoundRobin->new([qw/foo bar/]);
is $dwr->remove('foo'), 1, 'removed foo';
is $dwr->remove('hoge'), 0, 'hoge is not found';
is $dwr->remove(), undef, 'error';

save()

When destroyed $guard is gone, will return to the saved state.

my $dwr = Data::WeightedRoundRobin->new([qw/foo bar/]);
{
    my $guard = $drw->save;
    $drw->remove('foo');
    is $drw->next, 'bar';
}

# return to saved state
my $data = $dwr->next; # foo or bar

AUTHOR

xaicron <xaicron {at} cpan.org>

COPYRIGHT

Copyright 2011 - xaicron

LICENSE

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

SEE ALSO