# Amazon Neptune utility for GraphQL
<a name="tools-graphql"></a>

The Amazon Neptune utility for [GraphQL](https://graphql.org/) is an open-source Node.js command-line tool that can help you create and maintain a GraphQL API for a Neptune property-graph database (it does not yet work with RDF data). It is a no-code way to create a GraphQL resolver for GraphQL queries that have a variable number of input parameters and return a variable number of nested fields.

It has been released as an open-source project located at [https://github.com/aws/amazon-neptune-for-graphql](https://github.com/aws/amazon-neptune-for-graphql).

You can install the utility using NPM like this (see [Installation and Setup](tools-graphql-setup.md) for details):

```
npm i @aws/neptune-for-graphql -g
```

The utility can discover the graph schema of an existing Neptune property graph, including nodes, edges, properties, and edge cardinality. It then generates a GraphQL schema with the directives needed to map the GraphQL types to the nodes and edges the database, and auto-generates resolver code. The resolver code is designed to minimize latency by returning only the data requested by the GraphQL query.

You can also start with an existing GraphQL schema and an empty Neptune database, and let the utility infer the directives needed to map that GraphQL schema to the nodes and edges of data to be loaded into the database. Or, you can start with a GraphQL schema and directives that you've already created or modified.

The utility is capable of creating all the Amazon resources it needs for its pipeline, including the Amazon AppSync API, the IAM roles, the data source, schema, and resolver, and the Amazon Lambda function that queries Neptune.

**Note**  
Command-line examples here assume a Linux console. If you are using Windows, replace the backslashes ('\\') at the end of lines with carets ('^').

**Topics**
+ [Installing and setting up the Amazon Neptune utility for GraphQL](tools-graphql-setup.md)
+ [Scanning data in an existing Neptune database](tools-graphql-scan-existing.md)
+ [Starting from a GraphQL schema with no directives](tools-graphql-start-from-schema.md)
+ [Working with directives for a GraphQL schema](tools-graphql-schema-with-directives.md)
+ [Command-line arguments for the GraphQL utility](tools-graphql-cmd-line-args.md)