cachemyr

Cachemyr[/kaʃˈmɪə] is simple in-memory cache storage module for node.

Why started?

I was using node-cache before. While using, there was some error and we were suspecting memory overflow as one of the reason. Finally, that was not the reason, but I thought it would be good if possible to let user know when heap memory usage is close to allowed memory in node(usually 1.4G). Also, there was bit of performance upgrade:

State:

1. Write 100,000 key-value to storage
2. Read 100,000 data from storage with random key
3. Repeat 100 times

(node-cache)

====== Memory usage ====== 
heap total:88.4765625
heap used:51.40773010253906

======= R/W performance(Avg. of 100 times test) ==========
Write Avg: 53.61ms
Read Avg: 52.71ms

(cachemyr)

====== Memory usage ====== 
heap total:75.91796875
heap used:29.33899688720703

======= R/W performance(Avg. of 100 times test) ==========
Write Avg: 36.84ms
Read Avg: 53.12ms

It depends on state, but usually shows bit slower performance on reading, but way more fast on writing.

But yet node-cache has been almost 3~4 years and proved by lot of projects, this has only been a few month and needs more test and improvement to become stable. Hope you could help!

How to:

Install

// for 'npm' user
$ npm i cachemyr

// for 'yarn' user
$ yarn add cachemyr

Use

// TODO:

This is example for user:

const mc = require('cachemyr')

mc.put('key-1', 1)
console.log(mc.get('key-1')) // 1

mc.delete('key-1')
console.log(mc.get('key-1')) // null

mc.put('key-2', 2, 6000, (key, value) => {
    // called when data with key `key-2` has been expired (after 6 second)
})

console.log(mc.getLength()) // 1 (<'key-2', 2>)

API

put: void

Put key-value data to storage

Variable	Type	Description
key	string	Key of KV(key-value) data
value	any	Value of KV data
duration	number(optional)	Length of duration(ms) to keep this data
timeoutCB	Function(optional)	Callback function to be called when added data has been expired
overflowCB	Function(optional)	Callback function when memory usage of storage has overrun the value defined in configuration

get: any | null

Get value of key from storage. Returns null when there is no key.

Variable	Type	Description
key	string	Key of KV data
instantRemoval	boolean(optioanl)	Remove after get when set to true

remove: void

Remove key-value set from storage

Variable	Type	Description
key	string	Key of KV data

drop: void

Remove all data in storage

getLength: number

Return number of key-value set in storage

Contribution

Improvements, bug report & fix, document updates, suggestions, and stars are all welcome!

Build command:

$ yarn build // build module

$ yarn test // test module