AWS Neptune - Gremlin - JS

connect.js

const gremlin = require('gremlin');

const { traversal } = gremlin.process.AnonymousTraversalSource;
const { DriverRemoteConnection } = gremlin.driver;

const graph = traversal().withRemote(new DriverRemoteConnection('ws://graphdb:8182/gremlin', {}));

module.exports = { graph }

create.js

/* we use this object to reference vertex ID and vertex properties */
const { t: { id } } = gremlin.process;
const { cardinality: { single } } = gremlin.process;

/**
 * create a new vertex with Id, Label and properties
 * @param {String,Number} vertexId Vertex Id
 * @param {String} label Vertex Label
 */
const createVertex = async (vertexId, label) => {
  const vertex = await graph.addV(label)
    .property(id, vertexId)
    .property(single, 'name', 'John')
    .property(single, 'lastname', 'Lennon')
    .next();

  return vertex.value;
};

find.js

/**
 * find unique vertex with id and label
 * @param {String,Number} vertexId
 * @param {String} label
 */
const findVertex = async (vertexId, label) => {
  const vertex = await graph.V(vertexId).hasLabel(label).elementMap().next();
  return vertex.value;
};

list.js

/**
 * List all vertexes in db
 * @param {Number} limit
 */
const listAll = async (limit = 500) => {
  return graph.V().limit(limit).elementMap().toList();
};

main.js

/* run methods */
const main = async () => {

  /* create vertex */
  const customId = Math.random() * 1000000;
  console.log(await createVertex(customId, 'mylabel'));

  /* update vertex */
  console.log(await findVertex(customId, 'mylabel'));
  console.log(await updateVertex(customId, 'mylabel', 'Ringo'));
  console.log(await findVertex(customId, 'mylabel'));

  /* should return null */
  console.log(await findVertex(123412, 'mylabel'));
  
  /* should print all nodes with limit = 10 */
  console.log(await listAll(10));
};

main();

update.js

/* we use this object to reference vertex ID and vertex properties */
const { t: { id } } = gremlin.process;
const { cardinality: { single } } = gremlin.process;

/**
 * Update Vertex Properties
 * @param {String,Number} vertexId Vertex Id
 * @param {String} label Vertex Label
 * @param {String} name Vertex Name Property
 */
const updateVertex = async (vertexId, label, name) => {
  const vertex = await graph.V(vertexId).property(single, 'name', name).next();
  return vertex.value;
};