neo4j_facebook_example.rb

require 'rubygems'
require 'json'
require 'rest_client'

def create_person(name)
  JSON.parse RestClient.post( "http://localhost:8988/neo4jr-social/nodes", :name => name  )
end

def make_mutual_friends(node1, node2)
  RestClient.post "http://localhost:8988/neo4jr-social/nodes/#{node1['node_id']}/relationships", :to => node2['node_id'], :type => 'friends'
  RestClient.post "http://localhost:8988/neo4jr-social/nodes/#{node2['node_id']}/relationships", :to => node1['node_id'], :type => 'friends'
end

luke      = create_person('Luke Skywalker')
han_solo  = create_person('Han Solo')
chewy     = create_person('Chewbacca')
lando     = create_person('Lando')
akbar     = create_person('General Akbar')

make_mutual_friends(luke, han_solo)
make_mutual_friends(han_solo, chewy)
make_mutual_friends(han_solo, lando)
make_mutual_friends(lando, akbar)

suggestions = JSON.parse RestClient.get("http://localhost:8988/neo4jr-social/nodes/#{luke['node_id']}/recommendations?type=friends")
friend_suggestions = suggestions.map{|n| n['name']}.join(', ')

puts "Luke Skywalker should become friends with #{friend_suggestions}"

#RESULT:
# Luke Skywalker should become friends with Chewbacca, Lando

neo4j_linkedin_example.rb

require 'rubygems'
require 'json'
require 'rest_client'

def create_person(name)
  response = RestClient.post "http://localhost:8988/neo4jr-social/nodes", :name => name  
  JSON.parse(response)
end

def make_mutual_friends(node1, node2)
  RestClient.post "http://localhost:8988/neo4jr-social/nodes/#{node1['node_id']}/relationships", 
                  :to => node2['node_id'], 
                  :type => 'friends'

  RestClient.post "http://localhost:8988/neo4jr-social/nodes/#{node2['node_id']}/relationships", 
                  :to => node1['node_id'], 
                  :type => 'friends'
end

def get_degrees_of_seperation(start_node, destination_node)
  url = "http://localhost:8988/neo4jr-social/nodes/#{start_node['node_id']}/paths?to=#{destination_node['node_id']}&type=friends&depth=3&direction=outgoing"
  response = RestClient.get(url)
  JSON.parse(response)
end

luke      = create_person('Luke Skywalker')
han_solo  = create_person('Han Solo')
chewy     = create_person('Chewbacca')
lando     = create_person('Lando')
akbar     = create_person('General Akbar')

make_mutual_friends(luke, han_solo)
make_mutual_friends(han_solo, chewy)
make_mutual_friends(han_solo, lando)
make_mutual_friends(lando, akbar)

degrees = get_degrees_of_seperation(luke, lando)

degrees.each do |path|
  puts path.map{|node| node['name'] || node['type']}.join(' => ') 
end

#RESULT:
# Luke Skywalker => friends => Han Solo => friends => Lando

rgl_example.rb

# http://github.com/fmeyer/rgl
require 'rubygems'
require 'rgl/adjacency'
require 'rgl/dot'
graph = RGL::DirectedAdjacencyGraph.new
graph.add_edge 'Johnathan', 'Mark'
graph.add_edge 'Mark', 'Mary'
graph.add_edge 'Phill', 'Mary'
graph.add_edge 'Phill', 'Luke'

# Use DOT to visualize this graph: 
# http://graphviz.org/Download_macos.php
graph.write_to_graphic_file('jpg')
`open graph.jpg`