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NAME

Data::Riak::MapReduce - A map/reduce query

VERSION

version 0.10

SYNOPSIS

my $riak = Data::Riak->new;

my $mr = Data::Riak::MapReduce->new({
    riak => $riak,
    inputs => [ [ "products8", $arg ] ],
    phases => [
        Data::Riak::MapReduce::Phase::Map->new(
            language => "javascript",
            source => "
            function(v) {
              var m = v.values[0].data.toLowerCase().match(/\w*/g);
              var r = [];
              for(var i in m) {
                if(m[i] != '') {
                  var o = {};
                  o[m[i]] = 1;
                  r.push(o);
                }
              }
              return r;
            }
            ",
        ),
        Data::Riak::MapReduce::Phase::Reduce->new(
            language => "javascript",
            source => "
            function(v) {
              var r = {};
              for(var i in v) {
                for(var w in v[i]) {
                  if(w in r) r[w] += v[i][w];
                  else r[w] = v[i][w];
                }
              }
              return [r];
            }
            ",
        ),
    ]
});

my $results = $mr->mapreduce;

DESCRIPTION

A map/reduce query.

ATTRIBUTES

inputs

Inputs to this query. There are few allowable forms.

For a single bucket:

inputs => "bucketname"

For a bucket and key (or many!):

inputs => [ [ "bucketname", "keyname" ] ]

inputs => [ [ "bucketname", "keyname" ], [ "bucketname", "keyname2" ] ]

And finally:

inputs => [ [ "bucketname", "keyname", "keyData" ] ]

phases

An arrayref of phases that will be executed in order. The phases should be one of Data::Riak::MapReduce::Phase::Link, Data::Riak::MapReduce::Phase::Map, or Data::Riak::MapReduce::Phase::Reduce.

METHODS

mapreduce

Execute the mapreduce query.

To enable streaming, do the following:

my $results = $mr->mapreduce(chunked => 1);

AUTHOR

Andrew Nelson <anelson at cpan.org>

COPYRIGHT AND LICENSE

This software is copyright (c) 2012 by Infinity Interactive.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.