This is a client library for accessing Neo4j, a graph database, from Node.js. It uses Neo4j's REST API.
This library supports and has been tested against Neo4j 1.4, 1.5 and 1.6. We need to formally test 1.7 and 1.8, but it's being used in the wild against those versions of Neo4j seemingly without any issues.
npm install neo4j
To start, create a new instance of the GraphDatabase class pointing to your
Neo4j instance:
var neo4j = require('neo4j');
var db = new neo4j.GraphDatabase('http://localhost:7474');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.
Here's a simple example:
var node = db.createNode({hello: 'world'}); // instantaneous, but...
node.save(function (err, node) { // ...this is what actually persists.
if (err) {
console.err('Error saving new node to database:', err);
} else {
console.log('Node saved to database with id:', node.id);
}
});Because async flow in Node.js can be significantly 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.)
Please note that breaking changes to this library are very likely in the
near future as we consider an API overhaul, but the version number will always
respect semantic versioning. So if you specify this library as a
dependency in your package.json, please specify something like 0.2.x or
~0.2.6, not >=0.2.6. Thanks. =)
git clone [email protected]:thingdom/node-neo4j.git
cd node-neo4j
npm install && npm run clean
You'll also need a local Neo4j database instance for the tests:
curl http://dist.neo4j.org/neo4j-community-1.6-unix.tar.gz --O neo4j-community-1.6-unix.tar.gz
tar -zxvf neo4j-community-1.6-unix.tar.gz
mv neo4j-community-1.6 db
If you're new to Neo4j, read the Getting Started page. Start the server:
db/bin/neo4j start
Stop the server:
db/bin/neo4j stop
To run the tests:
npm test
Important: The tests are written assuming Neo4j >=1.7 and will now fail on prior Neo4j versions, but the library supports prior Neo4j versions just fine.
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 when this library is installed by 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');
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.
This library is licensed under the Apache License, Version 2.0.
If you encounter any bugs or other issues, please file them in the issue tracker.