NAME
Data::SearchEngine::ElasticSearch - ElasticSearch support for Data::SearchEngine
VERSION
version 0.21
SYNOPSIS
use Data::SearchEngine::Query;
use Data::SearchEngine::ElasticSearch;
my $dse = Data::SearchEngine::ElasticSearch->new(
servers => [ '127.0.0.1:9200' ]
);
my $query = Data::SearchEngine::Query->new(
index => 'tweets',
page => 1,
count => 10,
order => { _score => { order => 'asc' } },
type => 'query_string',
facets => {
etype => { terms => { field => 'etype' } },
author_organization_literal => { terms => { field => 'author_organization_literal' } },
author_literal => { terms => { field => 'author_literal' } },
source_literal => { terms => { field => 'source_literal' } },
}
);
my $results = $dse->search($query);DESCRIPTION
Data::SearchEngine::ElasticSearch is a backend for Data::SearchEngine. It aims to generalize the features of ElasticSearch so that application authors are insulated from some of the differences betwene search modules.
IMPLEMENTATION NOTES
This module is opinionated. ElasticSearch's query language and features are powerful and difficult to reign in. Therefore this module has taken some steps to bring things toward a more central feature set.
Incomplete
ElasticSearch's query DSL is large and complex. It is not well suited to abstraction by a library like this one. As such you will almost likely find this abstraction lacking. Expect it to improve as the author uses more of ElasticSearch's features in applications.
Resultes
The _index and _version keys will both be populated in the returned Data::SearchEngine::Item.
Explanations
Setting debug to a true value will cause <explain> to be set when the query is sent to ElasticSearch. You can find the explanation by examining the raw attribute of the Data::SearchEngine::Results object.
Queries
It is expected that if your Data::SearchEngine::Query object has any query set then it must also have a type.
The query is then passed on to ElasticSearch thusly:
$es->search(
# ...
query => { $query->type => $query->query }
# ...
);So if you want to do a query_string query, you would set up your query like this:
my $query = Data::SearchEngine::Query->new(
# ...
type => 'query_string',
query => { query => 'some query text' }
# ...
);See the documents for ElasticSearch's DLS for more details.
Indexing
ElasticSearch wants an index and type for each Item that is indexed. It is expected that you will populate these values in the item thusly:
my $item = Data::SearchEngine::Item->new(
id => $something,
values => {
index => 'twitter',
type => 'tweet',
# and whatever else
}
);
$dse->add($item);Filters
If you set multiple filters they will be ANDed together. If you want to change this behavior then you can supply an additional argument to the query method:
$dse->search($query, 'or');This defaults to 'and'.
Facets & Filters
If you use facets then any filters will be copied into the facet's facet_filter so that the facets are limited similarly to the results.
ATTRIBUTES
servers
The servers to which we'll be connecting.
transport
The transport to use. Refer to ElasticSearch for more information.
METHODS
add ([ $items ])
Add items to the index. Keep in mind that the Data::SearchEngine::Item should have values set for index and type.
engine
Returns the underlying ElasticSearch implementation.
present ($item)
Returns true if the Data::SearchEngine::Item is present. Uses the item's id.
remove_by_id ($item)
Remove the specified item from the index. Uses the item's id.
search ($query)
Search!
find_by_id ($index, $type, $id)
Find a document by it's unique id.
AUTHOR
Cory G Watson <gphat@cpan.org>
COPYRIGHT AND LICENSE
This software is copyright (c) 2012 by Cold Hard Code, LLC.
This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.