A GraphQL to Cypher query execution layer for Neo4j and JavaScript GraphQL implementations.

• Read the docs
• Read the changelog

neo4j-graphql-js is in active development. There are rough edges and APIs may change. Please file issues for any bugs that you find or feature requests.

Install

npm install --save neo4j-graphql-js 

Start with GraphQL type definitions:

const typeDefs = ` type Movie {  title: String  year: Int  imdbRating: Float  genres: [Genre] @relation(name: "IN_GENRE", direction: "OUT") } type Genre {  name: String  movies: [Movie] @relation(name: "IN_GENRE", direction: "IN") } `;

Create an executable schema with auto-generated resolvers for Query and Mutation types, ordering, pagination, and support for computed fields defined using the @cypher GraphQL schema directive:

import { makeAugmentedSchema } from 'neo4j-graphql-js'; const schema = makeAugmentedSchema({ typeDefs });

Create a neo4j-javascript-driver instance:

import { v1 as neo4j } from 'neo4j-driver'; const driver = neo4j.driver( 'bolt://localhost:7687', neo4j.auth.basic('neo4j', 'letmein') );

Use your favorite JavaScript GraphQL server implementation to serve your GraphQL schema, injecting the Neo4j driver instance into the context so your data can be resolved in Neo4j:

import { ApolloServer } from 'apollo-server'; const server = new ApolloServer({ schema, context: { driver } }); server.listen(3003, '0.0.0.0').then(({ url }) => { console.log(`GraphQL API ready at ${url}`); });

If you don't want auto-generated resolvers, you can also call neo4jgraphql() in your GraphQL resolver. Your GraphQL query will be translated to Cypher and the query passed to Neo4j.

import { neo4jgraphql } from 'neo4j-graphql-js'; const resolvers = { Query: { Movie(object, params, ctx, resolveInfo) { return neo4jgraphql(object, params, ctx, resolveInfo); } } };

A package to make it easier to use GraphQL and Neo4j together. neo4j-graphql.js translates GraphQL queries to a single Cypher query, eliminating the need to write queries in GraphQL resolvers and for batching queries. It also exposes the Cypher query language through GraphQL via the @cypher schema directive.

• Translate GraphQL queries to Cypher to simplify the process of writing GraphQL resolvers
• Allow for custom logic by overriding of any resolver function
• Work with graphql-tools, graphql-js, and apollo-server
• Support GraphQL servers that need to resolve data from multiple data services/databases
• Expose the power of Cypher through GraphQL via the @cypher directive

• Send a single query to the database
• No need to write queries for each resolver
• Exposes the power of the Cypher query language through GraphQL

See our detailed contribution guidelines.

See /examples

Full docs can be found on GRANDstack.io/docs

You can log out the generated cypher statements with an environment variable:

DEBUG=neo4j-graphql-js node yourcode.js 

This helps to debug and optimize your database statements. E.g. visit your Neo4J browser console at http://localhost:7474/browser/ and paste the following:

:params :params { offset: 0, first: 12, filter: {}, cypherParams: { currentUserId: '42' } } 

and now profile the generated query:

EXPLAIN MATCH (`post`:`Post`) WITH `post` ORDER BY post.createdAt DESC RETURN `post` { .id , .title } AS `post` 

You can learn more by typing:

:help EXPLAIN :help params