arangodb/Documentation/Books/Drivers/JS/Reference/Graph/VertexCollection.md

GraphVertexCollection API

The GraphVertexCollection API extends the Collection API with the following methods.

graphVertexCollection.remove

async graphVertexCollection.remove(documentHandle): Object

Deletes the vertex with the given documentHandle from the collection.

Arguments

• documentHandle: string

  The handle of the vertex to retrieve. This can be either the _id or the _key of a vertex in the collection, or a vertex (i.e. an object with an _id or _key property).

Examples

const graph = db.graph('some-graph');
const collection = graph.vertexCollection('vertices');

await collection.remove('some-key')
// document 'vertices/some-key' no longer exists

// -- or --

await collection.remove('vertices/some-key')
// document 'vertices/some-key' no longer exists

graphVertexCollection.documentExists

async graphVertexCollection.documentExists(documentHandle): boolean

Checks whether the vertex with the given documentHandle exists.

Arguments

• documentHandle: string

  The handle of the vertex to retrieve. This can be either the _id or the _key of a vertex in the collection, or a vertex (i.e. an object with an _id or _key property).

Examples

const graph = db.graph('some-graph');
const collection = graph.vertexCollection('vertices');

const exists = await collection.documentExists('some-key');
if (exists === false) {
  // the vertex does not exist
}

graphVertexCollection.document

async graphVertexCollection.document(documentHandle, [graceful]): Object

Alias: graphVertexCollection.vertex.

Retrieves the vertex with the given documentHandle from the collection.

Arguments

• documentHandle: string

  The handle of the vertex to retrieve. This can be either the _id or the _key of a vertex in the collection, or a vertex (i.e. an object with an _id or _key property).

• graceful: boolean (Default: false)

  If set to true, the method will return null instead of throwing an error if the vertex does not exist.

Examples

const graph = db.graph('some-graph');
const collection = graph.vertexCollection('vertices');

const doc = await collection.document('some-key');
// the vertex exists
assert.equal(doc._key, 'some-key');
assert.equal(doc._id, 'vertices/some-key');

// -- or --

const doc = await collection.document('vertices/some-key');
// the vertex exists
assert.equal(doc._key, 'some-key');
assert.equal(doc._id, 'vertices/some-key');

// -- or --

const doc = await collection.vertex('some-key', true);
if (doc === null) {
  // the vertex does not exist
}

graphVertexCollection.save

async graphVertexCollection.save(data): Object

Creates a new vertex with the given data.

Arguments

• data: Object

  The data of the vertex.

Examples

const db = new Database();
const graph = db.graph('some-graph');
const collection = graph.vertexCollection('vertices');
const doc = await collection.save({some: 'data'});
assert.equal(doc._id, 'vertices/' + doc._key);
assert.equal(doc.some, 'data');