@coolgk/cache

a javascript / typescript module

npm install @coolgk/cache

a redis wrapper

Report bugs here: https://github.com/coolgk/node-utils/issues

Examples

import { Cache } from '@coolgk/cache';
import { createClient } from 'redis';
// OR
// const { Cache } = require('@coolgk/cache');
// const { createClient } = require('redis');

const client = createClient({
    host: 'localhost',
    port: 12869,
    password: '----'
});

const cache = new Cache({
    redisClient: client
});

cache.set('abc', {a: 1}, 1).then(console.log); // 'OK'

cache.get('abc').then(console.log); // { a: 1 }

setTimeout(() => {
    cache.get('abc').then(console.log); // null
    client.quit();
}, 1500);

cache.getSetIfNull(
    'abc',
    () => Promise.resolve('data'),
    10
).then((v) => {
    console.log(v); // { a: 1 }
});

Promise.all([
    cache.set('x', 'val x'),
    cache.set('y', 'val y'),
    cache.set('z', 'val z')
]).then(
    () => Promise.all([
        cache.get('x').then(console.log), // val x
        cache.get('y').then(console.log), // val y
        cache.get('z').then(console.log) // val z
    ])
).then(
    () => Promise.all([
        cache.delete('x'),
        cache.delete('y'),
        cache.delete('z')
    ])
).then(
    () => Promise.all([
        cache.get('x').then(console.log), // null
        cache.get('y').then(console.log), // null
        cache.get('z').then(console.log) // null
    ])
);

Cache

Kind: global class

• Cache
  • new Cache(options)
  • .set(name, value, [expiry]) ⇒ promise
  • .get(name) ⇒ promise
  • .delete(name) ⇒ promise
  • .getSetIfNull(name, callback, [expiry]) ⇒ promise
  • .command(command, ...params) ⇒ promise

new Cache(options)

| Param | Type | Description | | --- | --- | --- | | options | object | | | [options.redisClient] | object | redis client from redis.createClient() redisClient needs to be passed in so the same connection can be used elsewhere and get closed outside this class |

cache.set(name, value, [expiry]) ⇒ promise

Kind: instance method of Cache

| Param | Type | Default | Description | | --- | --- | --- | --- | | name | string | | name of the variable | | value | * | | value is always JSON.stringify'ed | | [expiry] | number | 0 | expire time in seconds. 0 = never expire |

cache.get(name) ⇒ promise

Kind: instance method of Cache
Returns: promise - - cached value

| Param | Type | Description | | --- | --- | --- | | name | string | name of the variable |

cache.delete(name) ⇒ promise

Kind: instance method of Cache

| Param | Type | Description | | --- | --- | --- | | name | string | Array.<string> | name(s) of the variable |

cache.getSetIfNull(name, callback, [expiry]) ⇒ promise

get the cached value, if not set, resolve "callback()" and save the value then return it

Kind: instance method of Cache
Returns: promise - - cached value

| Param | Type | Default | Description | | --- | --- | --- | --- | | name | string | | name of the variable | | callback | function | | a callback function which returns a value or a promise | | [expiry] | number | 0 | expire time in seconds. 0 = never expire |

cache.command(command, ...params) ⇒ promise

Kind: instance method of Cache

| Param | Type | Description | | --- | --- | --- | | command | string | redis command to run | | ...params | array | params for the command |