ClusterUtils

ClusterUtils is a minilize key value store library which impilement by IPC for nodejs cluster. It's only 60 line code so it is easy to understand, best code for education ever!

Features:

Cluster share memory.

Cross worker event in cluster.

When using ClusterUtils?

If you use nodejs cluster and do not wanna using database to store data. Just wanna tiny memory based key/value datastore solution.

If you wanna trigger events between workers in cluster.

Lightweight application.

Only one producer application. (Because do not have resource lock).

How to use

You can use store engine easily.

const cluster = require('cluster');
// You must include this library after first include cluster library
const ClusterUtils = require("../index");

...

if (cluster.isMaster) {
	for (let i = 0; i < 8; i++) {
		cluster.fork();
	}
} else {
	if (cluster.worker.id == 1) {
		ClusterUtils.set('custom key', 6699);
	}
	if (cluster.worker.id == 2) {
		// You should wait for IPC sync memory progress. 
		// In this example, i use setTimeout 100.
		setTimeout(()=>{
			console.log(ClusterUtils.get('custom key'));
		}, 100);
	}
}

And you can trigger other worker event in cluster.

const cluster = require('cluster');
// You must include this library after first include cluster library
const ClusterUtils = require("../index");

...

if (cluster.isMaster) {
	for (let i = 0; i < 8; i++) {
		cluster.fork();
	}
} else {
	if (cluster.worker.id == 1) {
		ClusterUtils.on('SOME_EVENT', ()=>{
			console.log(`process ${cluster.worker.id} say hello`);
		});
	}
	if (cluster.worker.id == 2) {
		// You should wait for IPC sync memory progress. 
		// In this example, i use setTimeout 100.
		setTimeout(()=>{
			// trigger a event from other process
			ClusterUtils.emit('SOME_EVENT');
		}, 100);
	}
}

API

get(key)

Get data from datastore by key.

If no found, return undefined.

Arguments:

• key {String} : Key used to lookup the entry

set(key,value)

Add/Edit a element in the datastore.

Arguments:

• key {String} : Key used to lookup the entry
• value {object} : Value to store

del(key)

Delete a element fromd atastore by key.

Arguments:

• key {String} : Key used to delete the entry

clean()

Delete all element from datastore.

on(key, callback)

Listen a cross wroker event.

Arguments:

• key {String} : Key used to listen on
• callback {function} : Callback function when event trigger

once(key, callback)

Listen a cross wroker event only once.

Arguments:

• key {String} : Key used to listen on
• callback {function} : Callback function when event trigger

removeListener(key)

Remove a event from current wroker. This function will not remove other wroker's event.

Arguments:

• key {String} : Key used to listen on

emit(key, [callback])

Trigger a cross worker event.

Arguments:

• key {String} : Key used to listen on
• callback {function} (optional): Callback function when event trigger finished.

License

WTFPL