Simple Threading with JS through NodeJS Cluster

const thread = require("thread-process");

function temp() {
    console.log("Hello World ~Thread");
}

const thr = new Thread();
thr.store(temp);
thr.run();
thr.close();

Table of Contents

• Features
• Installing
• Initializing
• Properties
• Thread Class
  • Constructor
  • Storing functions
  • Global Variables Accessible
  • Running Functions
  • Running Multiple Threads
  • Events
  • Closing Threads
• Immediate Thread
• Example Usage

Features

• Supports "require" in "threaded" functions
• Supports storing both synchronous and asynchronous functions
• Multiple threads running simultaneously
• Thread emitted events
• Thread cleanup

Installing

Requires prior installation of NodeJS

$ npm install thread-process

Initializing

const thread = require("thread-process");

Properties

Thread.MAX_THREADS // Gets the maximum CPU count
Thread.OPEN_THREADS // Gets the count of how many threads are active

Thread Class

Constructor

new Thread(); // Constructing a thread with default settings
new Thread(function); // Stores a function

Storing Functions (Asynchronous)

(Async) returns the function stored

thr.store(function);
thr.store(function, function.name); // Override the function name or provide one that is missing

Global Variables Accessible

THREAD_DATA // (Object) Contains all the functions stored
FOCUSED_FUNCTION // (String) The most recent function
RETURN(data); // Sends data from the function to the main thread

Running Functions (Asynchronous)

Run the most recent function stored or executed by the thread

(Async) returns the data returned by the function executed

thr.run();
thr.runOnce(); // Closes the thread after running

Run target function stored in the thread

thr.run("temp"); // Runs temp()

Run with arguments

thr.run(function.name, [arg1,arg2,arg3]) // temp(arg1, arg2, arg3)
thr.run([arg1,arg2,arg3])

Running Multiple Threads (Asynchronous)

(Async) returns data as an Array

Thread.runAll(thr.run(), ...);

Events

Event handling can make life much easier!

thr.on("completed", (data)=>{}); // Contains the returned data
thr.on("returned", (data)=>{}); // Contains data returned by RETURN(data);

Closing Threads

thr.close();

Immediate Thread (Asynchronous)

Runs a function within a thread and immediately closes the thread upon completion

(Async) returns the data returned by the function executed

Thread.exec(function);
Thread.exec(function, [arg1,arg2,arg3]);

Example Usage

Using thread constiables

const temp = (text)=>{
    console.log(THREAD_DATA);
    console.log(FOCUSED_FUNCTION); // Outputs "temp"
}
async function main(){
    const tp = new Thread();
    await tp.store(temp);
    await tp.runOnce();
}
main();

Asynchronous management of threads & passing values

const temp = async (text)=>{
    console.log(`Async! ${text}`);
}
async function main(){
    const tp = new Thread();
    await tp.store(temp);
    await tp.runOnce(["~ Thread"]);
}
main();

Multiple stored functions

const func1 = ()=>{console.log("First function!")}
const func2 = ()=>{console.log("Second function!")}
async function main(){
    const tp = new Thread();
    await tp.store(func1);
    await tp.store(func2);
    await tp.runOnce("func1");
}
main();

Using then instead of async/await

const temp = ()=>{console.log("Hello World!")}
const tp = new Thread();
tp.store(temp).then((result)=>{tp.runOnce();});

Running simultaneous threads

const temp = ()=>{return "Hello";}
const tp = new Thread(temp);
const tp2 = new Thread(temp);
Thread.runAll(tp.runOnce(), tp.runOnce()).then((result)=>console.log(result));

Running with events

const temp = ()=>{RETURN("Hello")};
const tp = new Thread(temp);
tp.on("returned", (data)=>{
    console.log(data);
    tp.close();
});
tp.run();