Graph Schema JSON utility library

Install

npm install @neo4j/graph-schema-utils

How to consume

There are two parts to this repo:

1. A JSON schema that describes how a graph schema should be expressed in JSON.
2. Utility functions that help the consumers to validate and work with a graph schema.

JSON-schema

The JSON that describes the shape of a graph schema is available in the source code (packages/json-schema/json-schema.json) and published on: https://dist.neo4j.org/json-graph-schema/ (to be published, not in place yet)

Validate

This function is needed to perform a validation on a graph schema. The validateSchema function compares the output against the JSON schema.

import { validateSchema } from "@neo4j/graph-schema-utils";

validateSchema(jsonSchema, graphSchema);

Parse

Since the references in the JSON document are references by id:s, there's a parser utility that hydrates the references and makes it easy to work with the schema.

import { formatters } from "@neo4j/graph-schema-utils";

const parsed = formatters.json.fromJson(graphSchemaJsonString);

Model

You can also create a schema model programatically. Example:

import { model } from "@neo4j/graph-schema-utils";

const labels = [
  new model.NodeLabel("l1", "Person"),
  new model.NodeLabel("l1", "Movie"),
];

const relationshipTypes = [new model.RelationshipType("rt1", "ACTED_IN")];

const properties = [
  new model.Property("name", new model.PropertyBaseType("string"), true),
  new model.Property("title", new model.PropertyBaseType("string"), true),
  new model.Property(
    "roles",
    new model.PropertyArrayType(new model.PropertyBaseType("string")),
    false
  ),
];

const nodeObjectTypes = [
  new model.NodeObjectType("n1", [labels[0]], [properties[0]]), // (:Person {name}) node type
  new model.NodeObjectType("n2", [labels[1]], [properties[1]]), // (:Movie {title}) node type
];

const relationshipObjectTypes = [
  // (:Person {name})-[:ACTED_IN {roles}]->(:Movie {title})
  new model.RelationshipObjectType(
    "r1",
    relationshipTypes[0],
    nodeObjectTypes[0],
    nodeObjectTypes[1],
    [properties[2]]
  ),
];

const graphSchema = new model.GraphSchema(
  nodeObjectTypes,
  relationshipObjectTypes
);

Serialize

If you need to transport or persist the schema, you can serialize the model into the JSON represenation.

import { formatters } from "@neo4j/graph-schema-utils";

const serialized = formatters.json.toJson(graphSchema);

Contribute

We welcome contributions to this repo. Fork this repo and open a PR!

Run test

To run a single test run:

npm run test

To watch for changes and run tests on change:

npm run test:watch

Build

To build the TypeScript:

npm run build