Neolixir

A declarative ORM abstraction layer for Neo4j. Provides model definition via polymorphic classes, schema definition, property typing, query abstraction, event handling and session management.

Documentation

Detailed documentation coming soon. In the meantime, please see the Quick Start section below.

You can also review the slides from the original Montréal-Python presentation here.

Quick Start

Installation

The current stable version requires py2neo 2.0, which requires Python 2.7+.

NOTE: Neo4j 3.0+ and Python 3.0+ support is currently still under development.

Neolixir is now available on PyPI, so you can just install directly with pip:

pip install neolixir

Basic Usage

Define a model:

from neolixir import *

class Person(Node):
    name = String()
    born = DateTime()
    friends = RelOut('friends_with')

Set some values:

>>> bob = Person()
>>> bob
<Person (0x16cf310): 
Id = None
Descriptors = ['born', 'friends', 'name']
Properties = {}
>
>>> bob.name = 'Bob'
>>> bob.born = '1970-01-01'
>>> bob
<Person (0x16cf310): 
Id = None
Descriptors = ['born', 'friends', 'name']
Properties = {'born': '1970-01-01 00:00:00', 'name': u'Bob'}
>

Add a friend:

>>> alice = Person()
>>> alice.name = 'Alice'
>>> bob.friends.append(alice)
<Relationship (0x16ef850): (None)-[None:friends_with]->(None) {}>
>>> bob.friends
[<Person (0x16e83d0): 
Id = None
Descriptors = ['born', 'friends', 'name']
Properties = {'name': u'Alice'}
>]

If your Neo4j server requires authentication:

>>> metadata.authenticate('user', 'password')
True

Commit the session:

>>> metadata.session.commit()
>>> bob.id
315
>>> alice.id
316

Reload from database:

>>> metadata.session.clear()
>>> bob = Person.get(315)
>>> bob
<Person (0x17971d0): 
Id = 315
Descriptors = ['born', 'friends', 'name']
Properties = {u'born': u'1970-01-01 00:00:00', u'name': u'Bob', u'__class__': u'Person'}
>
>>> bob.friends
[<Person (0x17c3210): 
Id = 316
Descriptors = ['born', 'friends', 'name']
Properties = {u'name': u'Alice', u'__class__': u'Person'}
>]
>>> bob.friends.rels()
[<Relationship (0x17c3050): (315)-[155:friends_with]->(316) {u'__class__': u'Relationship'}>]

Development

This software is open-source and released under the MIT License. Feel free to clone, modify and contribute.

If contributing code, please follow the existing coding style and make sure to run and update the tests.

Running the Tests

Tests are based on pytest and are located in the tests/ directory.

In order to run the tests:

1. Set up a neo4j instance running at localhost:7474. Alternatively, you may specify a different database using the NEO4J_TEST_SERVER variable, e.g. NEO4J_TEST_SERVER=localhost:7480.

   WARNING: running the tests will clear the contents of this database.

2. Make sure the virtualenv Python package is installed.

3. Clone this repo and go to its root directory.

4. The first time, you will need to build the test virtualenv:

   $ ./virtualenv/build.sh

5. Activate the virtualenv you wish to test against, by default:

   $ source ./virtualenv/python-2.7-py2neo-2.0.8/bin/activate

6. Run the tests:

   $ py.test tests

   Or, if your server is not at the default address:

   $ NEO4J_TEST_SERVER=localhost:7480 py.test tests

About

Developed and maintained by Ivo Tzvetkov at ChallengeU. Twitter: @ivotkv. Gmail: ivotkv.

Copyright (c) 2013 Ivaylo Tzvetkov, ChallengeU. Released under the terms of the MIT License.