NAME

    Catmandu::Store::MongoDB - A searchable store backed by MongoDB

SYNOPSIS

        # On the command line
        $ catmandu import -v JSON --multiline 1 to MongoDB --database_name bibliography --bag books < books.json
        $ catmandu export MongoDB --database_name bibliography --bag books to YAML
        $ catmandu count MongoDB --database_name bibliography --bag books --query '{"PublicationYear": "1937"}'
    
        # In perl
        use Catmandu::Store::MongoDB;
    
        my $store = Catmandu::Store::MongoDB->new(database_name => 'test');
    
        my $obj1 = $store->bag->add({ name => 'Patrick' });
    
        printf "obj1 stored as %s\n" , $obj1->{_id};
    
        # Force an id in the store
        my $obj2 = $store->bag->add({ _id => 'test123' , name => 'Nicolas' });
    
        my $obj3 = $store->bag->get('test123');
    
        $store->bag->delete('test123');
    
        $store->bag->delete_all;
    
        # All bags are iterators
        $store->bag->each(sub { ... });
        $store->bag->take(10)->each(sub { ... });
    
        # Search
        my $hits = $store->bag->search(query => '{"name":"Patrick"}');
        my $hits = $store->bag->search(query => '{"name":"Patrick"}' , sort => { age => -1} );
        my $hits = $store->bag->search(query => {name => "Patrick"} , start => 0 , limit => 100);
        my $hits = $store->bag->search(query => {name => "Patrick"} , fields => {_id => 0, name => 1});
    
        my $next_page = $hits->next_page;
        my $hits = $store->bag->search(query => '{"name":"Patrick"}' , page => $next_page);
    
        my $iterator = $store->bag->searcher(query => {name => "Patrick"});
        my $iterator = $store->bag->searcher(query => {name => "Patrick"}, fields => {_id => 0, name => 1});
    
        # Catmandu::Store::MongoDB supports CQL...
        my $hits = $store->bag->search(cql_query => 'name any "Patrick"');

DESCRIPTION

    A Catmandu::Store::MongoDB is a Perl package that can store data into
    MongoDB databases. The database as a whole is called a 'store'.
    Databases also have compartments (e.g. tables) called Catmandu::Bag-s.

METHODS

 new(database_name => $name, %connectio_opts)

 new(database_name => $name , bags => { data => { cql_mapping =>
 $cql_mapping } })

    Create a new Catmandu::Store::MongoDB store with name $name. Optionally
    provide connection parameters (see MongoDB::MongoClient for possible
    options).

    The store supports CQL searches when a cql_mapping is provided. This
    hash contains a translation of CQL fields into MongoDB searchable
    fields.

     # Example mapping
     $cql_mapping = {
         indexes => {
              title => {
                op => {
                  'any'   => 1 ,
                  'all'   => 1 ,
                  '='     => 1 ,
                  '<>'    => 1 ,
                  'exact' => {field => [qw(mytitle.exact myalttitle.exact)]}
                } ,
                sort  => 1,
                field => 'mytitle',
                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 mapped into the MongoDB field 'mytitle',
    except for the 'exact' operator. In case of 'exact' both the
    'mytitle.exact' and 'myalttitle.exact' fields will be searched.

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

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

        package Biblio::Search;
    
        sub normalize_title {
           my ($self,$title) = @_;
           # delete all bad characters
           my $new_title =~ s{[^A-Z0-9]+}{}g;
           $new_title;
        }
    
        1;

 bag($name)

    Create or retieve a bag with name $name. Returns a Catmandu::Bag.

 client

    Return the MongoDB::MongoClient instance.

 database

    Return a MongoDB::Database instance.

 drop

    Delete the store and all it's bags.

Search

    Search the database: see Catmandu::Searchable. This module supports an
    additional search parameter:

        - fields => { <field> => <0|1> } : limit fields to return from a query (see L<MongoDB Tutorial|https://docs.mongodb.org/manual/tutorial/project-fields-from-query-results/>)

SEE ALSO

    Catmandu::Bag, Catmandu::Searchable , MongoDB::MongoClient

AUTHOR

    Nicolas Steenlant, <nicolas.steenlant at ugent.be>

CONTRIBUTORS

    Johann Rolschewski, <jorol at cpan.org>

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.