keyv-arango

ArangoDB store for Keyv: simple key-value storage with support for multiple backends.

Install

npm install keyv-arango keyv arangojs
# or
yarn add keyv-arango keyv arangojs
# or
pnpm add keyv-arango keyv arangojs

Usage

import Keyv from 'keyv'
import { KeyvArango, KeyvArangoOptions } from 'keyv-arango'

const options: KeyvArangoOptions = {
  // An ArangoDB database config object. This field is required.
  // If no database is specified, the default `_system` database will be used.
  config: {
    url: process.env.ARANGO_URL
  },
  // All fields below are optional.
  cacheCollection: true, // whether to cache the collection instance in between data calls. Defaults to true.
  collectionName: 'keyv', // the name of the collection to use. Defaults to 'keyv'.
  expireAfter: 0, // how long to wait before expiring a key (in milliseconds). Defaults to 0.
  field: 'expireDate', // the name of the field which will store the expiration date. Defaults to 'expireDate'.
  namespace: null // the keyv namespace to use. Defaults to null.
}

const store = new KeyvArango(options)

const keyv = new Keyv({ store })

// From here on, you can use keyv as usual.

await keyv.set('foo', 'bar', 1000)

await keyv.get('foo')

ArangoDB and TTL Indexes

When using TTL indexes in ArangoDB is no guarantee that a key will be deleted at the exact time specified, only that the key will be deleted. ArangoDB runs a background thread which is responsible for cleaning up keys. The frequency of this thread is configurable, but defaults to 30 seconds.

This is an important caveat to keep in mind when using this library and ArangoDB in general. Without prior configuration, ArangoDB is not suitable for short-lived keys. When starting an ArangoDB instance the --ttl.frequency option can be used to configure the frequency of the background thread. For more information, see the ArangoDB documentation. In fact the CI tests for this library use a frequency of 1 second to ensure that the tests pass in a timely manner.