Neo4j v3 Setup

Usage from Ruby

Installation of Neo4j Server and start server:

rake neo4j:install[community-2.1.3]
rake neo4j:start

Example, Open a session to the neo4j server database (in IRB for example)

  Neo4j::Session.open(:server_db)

After you have created a session you can now use the database, see below.

Usage from JRuby

On JRuby you can access the database in two different ways: using the embedded db or the server db.

Example, Open a session to the neo4j embedded database (running in the same JVM)

  session = Neo4j::Session.open(:embedded_db, '/folder/db')
  session.start

Usage with a remote Server

Example of a rails config/application.rb file:

config.neo4j.session_options = { basic_auth: { username: 'foo', password: 'bar'} } 
config.neo4j.session_type = :server_db 
config.neo4j.session_path = 'http://localhost:7474'

All options from HTTParty are available. For more Information see http://rdoc.info/github/jnunemaker/httparty/HTTParty/ClassMethods

See https://gist.github.com/andreasronge/11189170 how to configure the Neo4j::Session with basic authentication from a none rails application.

A _classname property is added to all nodes during creation to store the object's class name. This prevents an extra query to the database when wrapping the node in a Ruby class. To change the property name, add this to application.rb:

config.neo4j[:class_name_property] = :new_name

Usage from heroku

Add a Neo4j db to your application:

heroku addons:add graphenedb

Example of a rails config/application.rb file:

config.neo4j.session_type = :server_db 
config.neo4j.session_path = ENV["GRAPHENEDB_URL"] || 'http://localhost:7474'

Usage from Rails

 rails new myapp -m http://andreasronge.github.com/neo4j/neo4j.rb -O
 cd myapp
 rake neo4j:install[community-2.0.2]
 rake neo4j:start

 rails generate scaffold User name:string email:string
 rails s
 open http://localhost:3000/users

Or manually modify the rails config file config/application.rb:

require 'neo4j/railtie'

module Blog
  class Application < Rails::Application
     # This is for embedded db, only available from JRuby
     #config.neo4j.session_type = :embedded_db # or server_db
     #config.neo4j.session_path = File.expand_path('neo4j-db', Rails.root) # or http://localhost:port
  end
end

You can skip Active Record by using the -O flag when generating the rails project.