Neo4J + GraphQL — Toy example using graphql-ruby and neo4jrb

graphql.rb

require 'graphql'
require 'neo4j'

neo4j_url = ENV['NEO4J_URL'] || 'http://localhost:7474'
session = Neo4j::Session.open(:server_db, neo4j_url)


class Author
  include Neo4j::ActiveNode
  id_property :id_author
  property :name
  property :cites
  property :h_index
  has_many :out, :publications, model_class: :Publication, type: 'AUTHOR_OF'
end

class Publication
  include Neo4j::ActiveNode
  id_property :id
  property :title
  property :year
  property :citations
  property :num_authors
  property :has_more_authors
  property :journal_id
end

PublicationType = GraphQL::ObjectType.define do
  name "Publication"
  description "A Publication"

  field :title, !types.String
  field :year, types.Int
  field :citations, types.Int
  field :num_authors, types.Int
  field :has_more_authors, types.Boolean
  field :journal_id
end

AuthorType = GraphQL::ObjectType.define do
  name "Author"
  description "An author"

  field :id_author, !types.String, "The unique ID for this author"
  field :name, !types.String, "The name of the author"
  field :cites, !types.Int,  "The number of citations"
  field :h_index, !types.Int, "The HIndex of the author"
  field :publications, types[PublicationType]
end

QueryRoot = GraphQL::ObjectType.define do
  name "Query"
  description "The query root for this schema"

  field :author do
    type AuthorType
    description "Find an author by its id"
    argument :id_author, !types.String
    resolve -> (object, arguments, context) {
      Author.where(id_author: arguments['id_author']).first
    }
  end
end

OpusSchema = GraphQL::Schema.define {
  query QueryRoot
}

puts OpusSchema.execute('{ author: author(id_author: "XXXXX") { name, cites, h_index, publications { title, citations } } }' ).inspect