cache-storages.md

gw2api-client/src/cache/null

The default storage. Does no caching at all.

import cacheNull from 'gw2api-client/src/cache/null'
api.cacheStorage(cacheNull())

---

gw2api-client/src/cache/memory

Caches the data using a basic in-memory storage.

Options:

• gcTick (optional) - How often the garbage collection should clean out expired data (in ms). Defaults to 5 * 60 * 1000.

import cacheMemory from 'gw2api-client/src/cache/memory'

const options = {
  gcTick: 5 * 60 * 1000
}

api.cacheStorage(cacheMemory(options))

---

gw2api-client/src/cache/browser

Caches the data in-memory but saves a persistent version into IndexedDB to hydrate the cache from on page load.

Options:

• storageKey (optional) - The cache key. Defaults to gw2api-cache.
• gcTick (optional) - How often the garbage collection should clean out expired data (in ms). Defaults to 5 * 60 * 1000.
• persistDebounce (optional) - How much time has to pass between the API request and the persisting into storage (in ms). Defaults to 3 * 1000.
• storageEngine - (optional) - A storage engine, with the same interface as idb-keyval

import cacheBrowserStorage from 'gw2api-client/src/cache/browser'

const options = {
  gcTick: 3 * 60 * 1000
}

api.cacheStorage(cacheBrowserStorage(options))

---

gw2api-client/src/cache/redis

Caches the data using Redis.

Options:

• redis - An instance of node_redis
• prefix (optional) - The prefix for the cache keys. Defaults to gw2api-.

import redis from 'redis'
import cacheRedis from 'gw2api-client/src/cache/redis'

const options = {
  redis: redis.createClient(),
  prefix: 'optional-prefix-'
}

api.cacheStorage(cacheRedis(options))

---

Custom

You can write a custom storage to fit your architecture. It has to be a function which takes a configuration object:

function cacheCustom (config) {
  // Do configuration things with the `config` object ...
  
  // Return an object with the implementations
  return {
    get: (key) => ...,
    ...
  }
}

api.cacheStorage(cacheCustom({foo: 'bar'}))

This function has to return an object containing implementations of the following functions, which all have to return a Promise object.

• get(key) - Gets a single value by key. Has to resolve to null if the value does not exist or is expired.
• mget([key, key, ...]) - Gets multiple values by keys. Resolves an array. Missing and expired elements have to be set to null. Has to maintain the order of keys when resolving into values.
• set(key, value, expiresInSeconds) - Sets a single value by key.
• mset([[key, value, expiresInSeconds], ...]) - Sets multiple values.
• flush() - Clears the cache data (only needed for tests).