neo4j

Node-Neo4j

This is a Node.js driver for Neo4j via it's REST API.

This driver has undergone a complete rewrite for Neo4j v2. It now only supports Neo4j 2.x — but it supports it really well. (If you're still on Neo4j 1.x, you can still use node-neo4j v1.)

What is Neo4j?

Neo4j is a transactional, open-source graph database. A graph database manages data in a connected data structure, capable of representing any kind of data in a very accessible way. Information is stored in nodes and relationships connecting them, both of which can have arbitrary properties. To learn more visit What is a Graph Database?

Installation

npm install neo4j --save

Usage

var neo4j = require('neo4j');
var db = new neo4j.GraphDatabase('http://username:password@localhost:7474');

db.cypher({
    query: 'MATCH (u:User {email: {email}}) RETURN u',
    params: {
        email: '[e-mail]',
    },
}, function (err, results) {
    if (err) throw err;
    var result = results[0];
    if (!result) {
        console.log('No user found.');
    } else {
        var user = result['u'];
        console.log(JSON.stringify(user, null, 4));
    }
});

Yields e.g.:

{
    "_id": 12345678,
    "labels": [
        "User",
        "Admin"
    ],
    "properties": {
        "name": "Alice Smith",
        "email": "[e-mail]",
        "emailVerified": true,
        "passwordHash": "..."
    }
}

Getting Help

If you're having any issues you can first refer to the API documentation.

If you encounter any bugs or other issues, please file them in the issue tracker.

We also now have a Google Group! Post questions and participate in general discussions there.

You can also ask a question on StackOverflow

Neo4j version support

Version	Ver 1.x	Ver 2.x
1.5-1.9	Yes	No
2.0	Yes	Yes
2.1	Yes	Yes
2.2	No	Yes

Neo4j feature support

Feature	Ver 1.x	Ver 2.x
Auth	No	Yes
Remote Cypher	Yes	Yes
Transactions	No	No
High Availability	No	No
Embedded JVM support	No	No

Node.js is asynchronous, which means this library is too: most functions take callbacks and return immediately, with the callbacks being invoked when the corresponding HTTP requests and responses finish.

Because async flow in Node.js can be quite tricky to handle, we strongly recommend using a flow control tool or library to help. Our personal favorite is Streamline.js, but other popular choices are async, Step, Seq, TameJS and IcedCoffeeScript.

Once you've gotten the basics down, skim through the full API documentation to see what this library can do, and take a look at @aseemk's node-neo4j-template app for a complete usage example. (The models/User.js file in particular is the one that interacts with this library.)

This library is officially stable at "v1", but "v2" will almost certainly have breaking changes to support only Neo4j 2.0 and generally improve the API (roadmap). You can be sheltered from these changes if you simply specify your package.json dependency as e.g. 1.x or ^1.0 instead of *.

Development

git clone [e-mail]:thingdom/node-neo4j.git
cd node-neo4j
npm install && npm run clean

You'll need a local installation of Neo4j (links), and it should be running on the default port of 7474 (neo4j start).

To run the tests:

npm test

This library is written in CoffeeScript, using Streamline.js syntax. The tests automatically compile the code on-the-fly, but you can also generate compiled .js files from the source ._coffee files manually:

npm run build

This is in fact what's run each time this library is published to npm. But please don't check the generated .js files in; to remove:

npm run clean

When compiled .js files exist, changes to the source ._coffee files will not be picked up automatically; you'll need to rebuild.

If you npm link this module into another app (like node-neo4j-template) and you want the code compiled on-the-fly during development, you can create an index.js file under lib/ with the following:

require('coffee-script/register');
require('streamline/register');
module.exports = require('./index._coffee');

But don't check this in! That would cause all clients to compile the code on-the-fly every time, which isn't desirable in production.

Changes

See the Changelog for the full history of changes and releases.

License

This library is licensed under the Apache License, Version 2.0.