Lightweight application memory cache-revalidate with minimal retry/fallback strategy

Npm installation

$ npm install cache-puppy

Basic Usage

import { CachePuppy } from 'cache-puppy';
import axios from 'axios';

const fetchPets = async (): Promise<IPet[]> => {
  return (await axios.get('www.pets/api/puppies')).data;
};

// cached pets with revalidation every 5 minutes
const cache = new CachePuppy<IPet[]>({
  initialData: fetchPets,
  revalidateFn: fetchPets,
  fallbackFn: [
    { petId: 23, name: 'bulldog' },
    { petId: 18, name: 'yorkshire terrier' },
  ],
  revalidateOpts: {
    retries: 5,
    interval: 1000 * 60 * 5, // 5 mins
  },
});

// some time later
console.log(cache.get()); // cached pets

Basic Features

• Simple to the point interface
• Linear and exponential retry strategies
• Provides custom Initial data, Revalidate and Fallback resolvers
• Allows plugging in custom cache setters/getters (can be useful for using other in memory caching connectors e.g Redis, Memcached)

API

CachePuppy(options: CacheOpts)

methods

| Property | Type | description | | ---------- | :--------------------------: | -------------------------- | | get | () => T | gets cache value | | set | (data: T) => Promise<void> | sets cache value | | revalidate | () => Promise< void > | revalidates cache | | teardown | () => void | gracfully tears down cache |

CacheOpts

An object type representing cache options

properties

| Property | Type | description | default | | --------------- | :----------------------------------: | ---------------------------------------------------- | ---------------------------------- | | initialData? | (() => T \| Promise< T >) \| T | initial cache data or a function to be resolved from | undefined | | revalidateFn? | (() => T \| Promise< T >) \| T | revalidation data or a function to be resolved from | undefined | | fallBackFn? | (() => T \| Promise< T >) \| T | fallback value or a function to be resolved from | undefined | | getterFn? | () => T \| undefined | custom cache getter function | undefined | | setterFn? | (data) => void | custom cache setter function | undefined | | revalidateOpts? | RevalidateOpts | revalidation options | defaultCacheOptions.revalidateOpts |

RevalidateOpts

An object cache revalidation options

properties

| Property | Type | description | default | | ------------------- | :---------------------------------------: | -------------------------------------------------------------- | -------------- | | strategy? | linear \| exponential | cache retry strategy | linear | | interval? | number | cache revalidation interval (ms) | 6000 (1 min) | | backOff? | number | retry backoff time (ms) | 300 | | exponentialBackoff? | number | retry exponential backoff time (ms) (for exponential strategy) | 10 | | retries | number | number of maximum retries | 3 | | onSuccess | (cache) => Promise< void > \| void | callback on revalidation success | undefined | | onRetriesReached | (cache, err) => Promise< void > \| void | callback on maximum retries reached | undefined |

Todo

• async getterFn/setterFn
• tests