neo4j-driver

Neo4j Driver for Javascript

An alpha-level database driver for a new Neo4j remoting protocol.

Note: This is in active development, the API is not stable. Please try it out and give us feedback, but expect things to break in the medium term!

Include module in Node.js application

var neo4j = require('lib/neo4j');

Include in web browser

A global object neo4j will be available.

<script src="lib/browser/neo4j-web.min.js"></script>

Usage examples (for both Node.js and browser environments)

var statement = ['MERGE (alice:Person {name:{name_a},age:{age_a}})',
    'MERGE (bob:Person {name:{name_b},age:{age_b}})',
    'CREATE UNIQUE (alice)-[alice_knows_bob:KNOWS]->(bob)',
    'RETURN alice, bob, alice_knows_bob'
];

var params = {
    name_a: 'Alice',
    age_a: 33,
    name_b: 'Bob',
    age_b: 44
};


// Create a Session object to contain all Cypher activity.
var driver = neo4j.driver("bolt://localhost");
var session = driver.session();

// Run a Cypher statement within an implicit transaction
// The streaming way:
session.run(statement.join(' '), params).subscribe({
    onNext: function(record) {
        // On receipt of RECORD
        for(var i in record) {
            console.log(i, ': ', record[i]);
        }
    }, onCompleted: function() {
        session.close();
    }, onError: function(error) {
        console.log(error);
    }
});

// or
// the Promise way, where the complete response is collected:
session.run(statement.join(' '), params)
    .then(function(records){
        records.forEach(function(record) {
            for(var i in record) {
                console.log(i, ': ', record[i]);
            }
        });
        session.close();
    })
    .catch(function(error) {
        console.log(error);
    });

Building

npm install 
npm build

This produces browser-compatible standalone files under lib/browser and a Node.js module version under lib/.
See files under examples/ on how to use.

Testing

./runTests.sh

This runs the test suite against a fresh download of Neo4j.
Or npm test if you already have a running version of a compatible Neo4j server.

Testing on windows

Running tests on windows requires PhantomJS installed and its bin folder added in windows system variable Path.
To run the same test suite, run .\runTest.ps1 instead in powershell with admin right.
The admin right is required to start/stop Neo4j properly as a system service.
While there is no need to grab admin right if you are running tests against an existing Neo4j server using npm test.

A note on numbers and the Integer type

For this driver to fully map to the Neo4j type system handling of 64-bits Integers is needed.
Javascript can saftely represent numbers between -(253 - 1) and (253 - 1).
Therefore, an Integer type is introduced.

Write integers

Number written directly e.g. session.run("CREATE (n:Node {age: {age}})", {age: 22}) will be of type Float in Neo4j.
To write the age as an integer the neo4j.int method should be used.
E.g. session.run("CREATE (n:Node {age: {age}})", {age: neo4j.int(22)}).

Read integers

To get the value of a from Neo4j received integer, the safeast way would be to use the .toString() method on an Integer object.
E.g. console.log(result.age.toString()).
To check if a variable is of the Integer type, the method neo4j.isInt(variable) can be used.