r-memory-cache

Installation

npm install r-memory-cache --save

Usage

import { createCache } from 'r-memory-cache'
const cache = createCache('LRU', { capacity: 2 })

cache.type // 'LRU'
cache.capacity // 2
cache.length // 0

cache.put('key', 'value')
cache.get('key') // 'value'
cache.length // 1

cache.del('key')
cache.get('key') // undefined

cache.put('key1', 'value1')
cache.put('key2', 'value2')
cache.put('key3', 'value3')

cache.get('key1') // undefined
cache.get('key2') // 'value2'
cache.get('key3') // 'value3'

// empty the cache
cache.clear()
cache.length // 0

API

createCache(type[, options])

import { createCache } from 'r-memory-cache'

const lruCache = createCache('LRU')
const lruCache2 = createCache('LRU', { capacity: 100 })
const lfuCache = createCache('LFU')
const fifoCache = createCache('FIFO')

type:

• 'LRU'
• 'LFU'
• 'FIFO'

options:

{
  // default: 64
  capacity: number
}

put(key, value)

The put method adds or updates an entry.

const cache = createCache('LRU')
cache.put(1, 1)

get(key)

The get method returns a specified entry by key.

const cache = createCache('LRU')
cache.put(1, 1)
cache.get(1) // 1

del(key)

The del method removes the specified entry by key.

const cache = createCache('LRU')
cache.put(1, 1)
cache.get(1) // 1
cache.del(1)
cache.get(1) // undefined

keys()

The keys method returns a array that contains the keys for each entry in the cache instance.

const cache = createCache('LRU')
cache.put(1, 1)
cache.put('a', 'a')
cache.keys() // [1, 'a']

clear()

The clear method removes all entries.

const cache = createCache('LRU')
cache.put(1, 1)
cache.put(2, 2)
cache.clear()
cache.get(1) // undefined
cache.get(2) // undefined

length

The length property returns the number of entries in a cache instance.

const cache = createCache('LRU')
cache.length // 0
cache.put(1, 1)
cache.length // 1

capacity

The capacity property returns the largest amount of entries that can be contained in a cache instance.

const cache = createCache('LRU')
cache.capacity // 64

const cache2 = createCache('LRU', { capacity: 2 })
cache2.capacity // 2
cache2.put(1, 1)
cache2.put(2, 2)
cache2.put(3, 3)
cache2.get(1) // undefined
cache2.get(2) // 2
cache2.get(3) // 3