How to insert a new data in mongoDB using worker thread in nodejs

Question

I want to insert data into the mongoDB using worker thread

Right now I have a worker file, whole purpose of worker file is to save the data into the mongoDB and mainjs is sending the name of the agent that I want to save into the mongoDB

worker.js

const { workerData, parentPort } = require('worker_threads')
const Agent = require('../models/agent')


console.log("Worker thread is running like a hell: ",  workerData)


    const processRecord =  async () => {
      
       const agent = new Agent({agent:workerData})
                
        try {
            await agent.save()
        }catch(e) {
            console.log(e)
        }
    }

    processRecord();

main.js

const express = require('express')
const router = new express.Router()
const { Worker } = require('worker_threads')

router.post('/agent', async (req, res) => {        
    function runService(workerData) {
        return new Promise((resolve, reject) => {
          const worker = new Worker('../src/router/worker.js', { workerData });
          worker.on('message', resolve);
          worker.on('error', reject);
          worker.on('exit', (code) => {
            if (code !== 0)
              reject(new Error(`Worker stopped with exit code ${code}`));
          })
        })
      }
      
      async function run() {
        const result = await runService('john wick')
        console.log("this is from main thread " + result);
      }
      
      run().catch(err => console.error(err))
})

When I try to save the data using worker thread then I am getting this error:

MongooseError: Operation `agents.insertOne()` buffering timed out after 10000ms
    at Timeout.setTimeout (F:\node\insuredmine\node_modules\mongoose\lib\drivers\node-mongodb-native\collection.js:184:20)
    at ontimeout (timers.js:436:11)
    at tryOnTimeout (timers.js:300:5)
    at listOnTimeout (timers.js:263:5)
    at Timer.processTimers (timers.js:223:10)

and when I run the same line of code without worker thread then its running fine.

Answer 1

You would need to configure mongoose and connect to MongoDB within a worker thread because Worker has isolated env ie its own event loop etc. If you are using a Worker to save data to MongoDB for just learning purposes then it's ok otherwise no use of a Worker here. Workers only useful when you have long-running synchronous tasks to perform for example encrypting a file, resizing an image or complex data processing, sorting large data, etc.

You can refer to this article for example code https://henrikgronvall.com/articles/nodejs-worker-threads/