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NAME

Catmandu::Store::OpenSearch - A searchable store backed by Opensearch

SYNOPSIS

# From the command line

# Import data into OpenSearch
$ catmandu import JSON to OpenSearch --bag catmandu < data.json

# Export data from OpenSearch
$ catmandu export OpenSearch --bag catmandu to JSON > data.json

# Export only one record
$ catmandu export OpenSearch --bag catmandu --id 1234

# Export using an OpenSearch query
$ catmandu export OpenSearch --bag catmandu --query "name:Recruitment OR name:college"

# Export using a CQL query (needs a CQL mapping)
$ catmandu export OpenSearch --bag catmandu --cql-query "name any college"

# From Perl

use Catmandu;

my $store = Catmandu->store('OpenSearch');

my $obj1 = $store->bag('catmandu')->add({ name => 'Patrick' });

printf "obj1 stored as %s\n" , $obj1->{_id};

# Force an id in the store
my $obj2 = $store->bag('catmandu')->add({ _id => 'test123' , name => 'Nicolas' });

# Commit all changes
$store->bag('catmandu')->commit;

$store->bag('catmandu')->delete('test123');

$store->bag('catmandu')->delete_all;

# All bags are iterators
$store->bag->each(sub { ... });
$store->bag->take(10)->each(sub { ... });

# Query the store using a simple OpenSearch query
my $hits = $store->bag->search(query => '(content:this OR name:this) AND (content:that OR name:that)');

# Native queries are also supported by providing a hash of terms
# See the OpenSearch manual for more examples
my $hits = $store->bag->search(
    query => {
        # All name.exact fields that start with 'test'
        prefix => {
            'name.exact' => 'test'
        }
    } ,
    limit => 1000);

# Catmandu::Store::OpenSearch supports CQL...
my $hits = $store->bag->search(cql_query => 'name any "Patrick"');

CONSTRUCTOR ARGUMENTS

  • hosts

    Type: ArrayRef[Str]

    Description: List of opensearch hosts

    Default: ["localhost:9200"]

    Optional

  • user

    Type: Str

    Description: username credential, when Basic Auth is needed

    Optional

  • pass

    Type: Str

    Description: password credential, when Basic Auth is needed

    Optional

  • secure

    Type: Bool (0 or 1)

    Description: access opensearch hosts over HTTPS

    Default: 0

    Optional

  • bags

    Type: HashRef

    Typically looks like

      {
      "<bag>": {
          "index": "<opensearch-index-name>",
          "mapping": {
          
          },
          "cql_mapping": {
          
          }
      }
  }

    Optionally provide for each bag a index to indicate which index to use. This defaults to the bag's name.

    Optionally provide for each bag a mapping which contains a OpenSearch schema for each field in the index (See "INDEX MAPPING").

    Optionally provide for each bag a cql_mapping to map fields to CQL indexes. (See "CQL MAPPING")

    Optionally provide for each bag an on_error error handler (See below).

INHERITED METHODS

This Catmandu::Store implements:

Each Catmandu::Bag in this Catmandu::Store implements:

INDEX MAPPING

The mapping contains a OpenSearch schema mappings for each bag defined in the index. E.g.

{
    properties => {
        title => {
            type => 'text'
        }
    }
}

See https://opensearch.org/docs/latest/field-types/ for more information on mappings.

These mappings can be passed inside a Perl program, or be written into a Catmandu 'catmandu.yml' configuration file. E.g.

# catmandu.yml
store:
    search:
       package: OpenSearch
       options:
         bags:
           mybag:
             mapping:
               properties:
                 title:
                   type: text

Via the command line these configuration parameters can be read in by using the name of the store, search in this case:

$ catmandu import JSON to search --bag mybag < data.json
$ catmandu export search --bag mybag to JSON > data.json

CQL MAPPING

Catmandu::Store::OpenSearch supports CQL searches when a cql_mapping is provided for each bag. This hash contains a translation of CQL fields into OpenSearch searchable fields.

# Example mapping
 {
   indexes => {
     title => {
       op => {
         'any'   => 1 ,
         'all'   => 1 ,
         '='     => 1 ,
         '<>'    => 1 ,
         'exact' => {field => [qw(mytitle.exact myalttitle.exact)]}
       } ,
       field => 'mytitle',
       sort  => 1,
       cb    => ['Biblio::Search', 'normalize_title']
     }
   }
}

The CQL mapping above will support for the 'title' field the CQL operators: any, all, =, <> and exact.

The 'title' field will be mapping into the OpenSearch field 'mytitle', except for the 'exact' operator. In case of 'exact' we will search both the 'mytitle.exact' and 'myalttitle.exact' fields.

The CQL mapping allows for sorting on the 'title' field. If, for instance, we would like to use a special OpenSearch field for sorting we could have written "sort => { field => 'mytitle.sort' }".

The callback field cb contains a reference to subroutines to rewrite or augment a search query. In this case, the Biblio::Search package contains a normalize_title subroutine which returns a string or an ARRAY of strings with augmented title(s). E.g.

package Biblio::Search;

sub normalize_title {
   my ($self,$title) = @_;
   my $new_title =~ s{[^A-Z0-9]+}{}g;
   $new_title;
}

1;

Also this configuration can be added to a catmandu.yml configuration file like:

# catmandu.yml
store:
    search:
       package: OpenSearch
       options:
         bags:
           book:
             mapping:
               properties:
                 title:
                   type: text
             cql_mapping:
               indexes:
                   title:
                       op:
                           'any': true
                           'all': true
                           '=':   true
                           '<>':  true
                           'exact':
                               field: [ 'mytitle.exact' , 'myalttitle.exact' ]
                       field: mytitle
                       sort: true
                       cb: [ 'Biblio::Search' , 'normalize_title' ]

Via the command line these configuration parameters can be read in by using the name of the store, search in this case:

$ catmandu export search --bag book -q 'title any blablabla' to JSON > data.json

COMPATIBILITY

This perl client works with the current Opensearch server 7.* at the moment of writing

ERROR HANDLING

Error handling can be activated by specifying an error handling callback for index when creating a store. E.g. to create an error handler for the bag 'data' index use:

my $error_handler = sub {
    my ($action, $response, $i) = @_;
    do_something_with_error($response);
};

my $store = Catmandu::Store::OpenSearch->new(
    bags => { data => { on_error => $error_handler } }
});

Instead of a callback, the following shortcuts are also accepted for on_error:

log: log the response

throw: throw the response as an error

ignore: do nothing

my $store = Catmandu::Store::OpenSearch->new(
    bags => { data => { on_error => 'log' } }
});

SEE ALSO

Catmandu::Store

AUTHOR

  • Nicolas Franck, <nicolas.franck at ugent.be>

IMPORTANT

This module is still a work in progress, and needs further testing using it in a production system

LICENSE AND COPYRIGHT

This program is free software; you can redistribute it and/or modify it under the terms of either: the GNU General Public License as published by the Free Software Foundation; or the Artistic License.

See http://dev.perl.org/licenses/ for more information.