EN
Node.js / JavaScript - run source code in thread
6 points
In this short article, we would like to show how we can create new thread in JavaScript and run it under Node.js.
The article shows how to use threads package that bases on worker threads Node.js feature.
Warning: worker threads are supported in Node.js 12+.
Simple steps:
1. install threads package using:
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npm install threads
2. create application files:
Exmaple main.js file:
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import { spawn, Thread, Worker } from 'threads';2
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const thread = await spawn(new Worker('./thread')); // loads ./thread.js file and creates thread4
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const result1 = await thread.addNumbers(1, 2);6
const result2 = await thread.subtractNumbers(1, 2);7
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console.log(`1 + 2 = ${result1}`);9
console.log(`1 - 2 = ${result2}`);10
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await Thread.terminate(thread); // releases resources if thread is longer not neededExmaple thread.js file:
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import { expose } from 'threads/worker';2
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const addNumbers = (a, b) => {4
return a + b;5
};6
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const subtractNumbers = (a, b) => {8
return a - b;9
};10
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expose({ addNumbers, subtractNumbers }); // expose more logic if neededNote: it is required to use separated files working with worker threads (e.g.
thread.jsfile in the above example).
3. run application using the command:
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node ./main.jsOutput:
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1 + 2 = 32
1 - 2 = -1Hint: to enable ES Modules (
import/exportkeywords) add"type": "module"property topackage.jsonfile.
Exmaple package.json file content:
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{2
"name": "threads-example",3
"version": "1.0.0",4
"description": "",5
"main": "main.js",6
"scripts": {7
"test": "echo \"Error: no test specified\" && exit 1"8
},9
"author": "",10
"license": "ISC",11
"type": "module",12
"dependencies": {13
"threads": "^1.7.0"14
}15
}