cayley-ruby

A ruby library for working with Google's Cayley graph database.

Installation

You can install it via gem

gem install cayley

Usage

Start your Cayley

# example using 30kmoviedata from cayley's repository
./cayley http --dbpath=30kmoviedata.nq.gz

You can use methods from Gremlin API documentation, just translate method names to snake style equivalent.

As a first step you need to create your client

require 'cayley'

graph = Cayley::Graph.new

# or

graph = Cayley::Graph.new(host: 'localhost', port: 64210)

Then using 30kmovies.nt db from cayley's repository you can do this

graph.vertex.get_limit(5)

graph.vertex('Humphrey Bogart').all

graph.v('Humphrey Bogart').all

graph.v('Humphrey Bogart').in('name').all

graph.v('Casablanca').in('name').all

graph.v.has('name', 'Casablanca').all

You can also use morphism

film_to_actor = graph.morphism
                     .out('/film/film/starring')
                     .out('/film/performance/actor')
graph.v
     .has('name', 'Casablanca')
     .follow(film_to_actor)
     .out('name').all

For more info take a look at Cayley's repository

Advanced

By default result of your queries are wrapped in Hashie::Mash so you can do things like these

graph.v.all.each do |result|
  puts result.id # instead of result['id']
end

If you want to use plain ruby hashes you can disable wrapping by

graph = Cayley::Graph.new(result_wrapper: nil)

Or you can use some custom wrapper if you put class instead of nil.

Debugging

If you are not sure why you are getting nil as a result of your query and you are not able to find out the solution you can turn on debug mode where used Gremlin query is printed out.

graph = Cayley::Graph.new(debug: true)

TODO

• logger
• tests