NAME

REST::Neo4p - Perl object bindings for a Neo4j database

SYNOPSIS

 use REST::Neo4p;
 REST::Neo4p->connect('http://127.0.0.1:7474');
 $i = REST::Neo4p::Index->new('node', 'my_node_index');
 $i->add_entry(REST::Neo4p::Node->new({ name => 'Fred Rogers' }),
                                      guy  => 'Fred_Rogers');
 $index = REST::Neo4p->get_index_by_name('my_node_index','node');
($my_node) = $index->find_entries('guy' => 'Fred_Rogers');
 $new_neighbor = REST::Neo4p::Node->new({'name' => 'Donkey Hoty'});
 $my_reln = $my_node->relate_to($new_neighbor, 'neighbor');

 $query = REST::Neo4p::Query->new("START n=node(".$my_node->id.")
                                   MATCH p = (n)-[]->()
                                   RETURN p");
 $query->execute;
 $path = $query->fetch->[0];
 @path_nodes = $path->nodes;
 @path_rels = $path->relationships;

Batch processing (see REST::Neo4p::Batch for more)

#!perl
# loader...
use REST::Neo4p;
use REST::Neo4p::Batch;

open $f, shift() or die $!;
batch {
  while (<$f>) {
   chomp;
   ($name, $value) = split /\t/;
   REST::Neo4p::Node->new({name => $name, value => $value});
  } 'discard_objs';
exit(0);

DESCRIPTION

REST::Neo4p provides a Perl 5 object framework for accessing and manipulating a Neo4j graph database server via the Neo4j REST API. Its goals are

(1) to make the API as transparent as possible, allowing the user to work exclusively with Perl objects, and

(2) to exploit the API's self-discovery mechanisms, avoiding as much as possible internal hard-coding of URLs.

Neo4j entities are represented by corresponding classes:

• Nodes : REST::Neo4p::Node

• Relationships : REST::Neo4p::Relationship

• Indexes : REST::Neo4p::Index

Actions on class instances have a corresponding effect on the database (i.e., REST::Neo4p approximates an ORM).

The class REST::Neo4p::Query provides a DBIesqe Cypher query facility.

Property Auto-accessors

Depending on the application, it may be natural to think of properties as fields of your nodes and relationships. To create accessors named for the entity properties, set

$REST::Neo4p::CREATE_AUTO_ACCESSORS = 1;

Then, when "set_property()" is used to first create and set a property, accessors will be created on the class:

$node1->set_property({ flavor => 'strange', spin => -0.5 });
printf "Quark has flavor %s\n", $node1->flavor;
$node1->set_spin(0.5);

If your point of reference is the database, rather than the objects, auto-accessors may be confusing, since once the accessor is created for the class, it will exist for all future instances:

print "Yes I can!\n" if REST::Neo4p::Node->new()->can('flavor');

but there is no fundamental reason why new nodes or relationships must have the property (it is NoSQL, after all). Therefore this is a choice for you to make; the default is no auto-accessors.

CLASS METHODS

connect()

REST::Neo4p->connect( $server )

get_node_by_id()

$node = REST::Neo4p->get_node_by_id( $id );

get_relationship_by_id()

$relationship = REST::Neo4p->get_relationship_by_id( $id );

get_index_by_name()

$node_index = REST::Neo4p->get_index_by_name( $name, 'node' );
$relationship_index = REST::Neo4p->get_index_by_name( $name, 'relationship' );

get_relationship_types()

@all_relationship_types = REST::Neo4p->get_relationship_types;

get_indexes(), get_node_indexes(), get_relationship_indexes()

@all_indexes = REST::Neo4p->get_indexes;
@node_indexes = REST::Neo4p->get_node_indexes;
@relationship_indexes = REST::Neo4p->get_relationship_indexes;

SEE ALSO

REST::Neo4p::Node,REST::Neo4p::Relationship,REST::Neo4p::Index, REST::Neo4p::Query, REST::Neo4p::Path, REST::Neo4p::Batch

AUTHOR

Mark A. Jensen
CPAN ID: MAJENSEN
majensen -at- cpan -dot- org

LICENSE

Copyright (c) 2012 Mark A. Jensen. This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.