feat: testing @wendelmax/tasklets

package.json

@@ -20,10 +20,11 @@
     "@faker-js/faker": "^8.4.1"
   },
   "dependencies": {
+    "@wendelmax/tasklets": "^2.2.0",
     "cli-progress": "^3.12.0",
     "draftlog": "^1.0.13",
     "mongodb": "^6.5.0",
     "pg": "^8.11.5",
     "sqlite3": "^5.1.7"
   }
-}
+}

src/index.js

@@ -1,18 +1,32 @@
-import { initialize } from "./cluster.js"
 import { getMongoConnection, getPostgresConnection } from './db.js'
 import cliProgress from 'cli-progress'
-import { setTimeout } from 'node:timers/promises'
+import Tasklets from '@wendelmax/tasklets'
+import path from 'node:path'
+
+// Configure Tasklets worker pool
+const tasklets = new Tasklets()
+tasklets.configure({
+    maxWorkers: 8,
+    minWorkers: 8,
+    idleTimeout: 30000,
+    workload: 'io',
+    adaptive: true,
+})
+
+// Worker module path (CJS module loaded via require() inside worker threads)
+const INSERT_WORKER = `MODULE:${path.join(import.meta.dirname, 'insert-worker.cjs')}`
+
+// Connect to databases
 const mongoDB = await getMongoConnection()
 const postgresDB = await getPostgresConnection()
+
 const ITEMS_PER_PAGE = 4000
-const CLUSTER_SIZE = 99
-const TASK_FILE = new URL('./background-task.js', import.meta.url).pathname
 
-// console.log(`there was ${await postgresDB.students.count()} items on Postgres, deleting all...`)
+// Clean Postgres before migration
 await postgresDB.students.deleteAll()
 
+// Async generator to paginate through MongoDB
 async function* getAllPagedData(itemsPerPage, page = 0) {
-
     const data = mongoDB.students.find().skip(page).limit(itemsPerPage)
     const items = await data.toArray()
     if (!items.length) return
@@ -23,39 +37,38 @@ async function* getAllPagedData(itemsPerPage, page = 0) {
 }
 
 const total = await mongoDB.students.countDocuments()
-// console.log(`total items on DB: ${total}`)
 
+// Progress bar
 const progress = new cliProgress.SingleBar({
     format: 'progress [{bar}] {percentage}% | {value}/{total} | {duration}s',
     clearOnComplete: false,
-}, cliProgress.Presets.shades_classic);
-
-progress.start(total, 0);
-let totalProcessed = 0
-const cp = initialize(
-    {
-        backgroundTaskFile: TASK_FILE,
-        clusterSize: CLUSTER_SIZE,
-        amountToBeProcessed: total,
-        async onMessage(message) {
-            progress.increment()
-
-            if (++totalProcessed !== total) return
-            // console.log(`all ${amountToBeProcessed} processed! Exiting...`)
-            progress.stop()
-            cp.killAll()
-
-            const insertedOnSQLite = await postgresDB.students.count()
-            console.log(`total on MongoDB ${total} and total on PostGres ${insertedOnSQLite}`)
-            console.log(`are the same? ${total === insertedOnSQLite ? 'yes' : 'no'}`)
-            process.exit()
-
-        }
-    }
-)
-await setTimeout(1000)
-
-for await (const data of getAllPagedData(ITEMS_PER_PAGE)) {
-    cp.sendToChild(data)
+}, cliProgress.Presets.shades_classic)
+
+progress.start(total, 0)
+
+// Process all pages in parallel using tasklets
+const promises = []
+
+for await (const items of getAllPagedData(ITEMS_PER_PAGE)) {
+    // Convert MongoDB docs to plain objects (strip ObjectId etc.)
+    const plainItems = items.map(({ name, email, age, registeredAt }) => ({ name, email, age, registeredAt }))
+
+    const promise = tasklets.run(INSERT_WORKER, plainItems).then(count => {
+        progress.increment(count)
+    })
+    promises.push(promise)
 }
 
+await Promise.all(promises)
+
+progress.stop()
+
+const insertedOnPostgres = await postgresDB.students.count()
+console.log(`total on MongoDB ${total} and total on PostGres ${insertedOnPostgres}`)
+console.log(`are the same? ${total === insertedOnPostgres ? 'yes' : 'no'}`)
+
+// Cleanup
+await mongoDB.client.close()
+await postgresDB.client.end()
+await tasklets.terminate()
+process.exit()

src/insert-worker.cjs

@@ -0,0 +1,37 @@
+// Worker module for Postgres batch inserts
+// Loaded by tasklets worker threads via MODULE: prefix
+
+const { Client } = require('pg')
+
+async function insertBatch(items) {
+    const client = new Client({
+        user: 'erickwendel',
+        host: process.env.POSTGRES_HOST || 'localhost',
+        database: 'school',
+        password: 'mypassword',
+        port: 5432,
+    })
+
+    await client.connect()
+
+    try {
+        // Build a single bulk INSERT for performance
+        const values = []
+        const placeholders = []
+        let idx = 1
+
+        for (const item of items) {
+            placeholders.push(`($${idx++}, $${idx++}, $${idx++}, $${idx++})`)
+            values.push(item.name, item.email, item.age, item.registeredAt)
+        }
+
+        const query = `INSERT INTO students (name, email, age, registered_at) VALUES ${placeholders.join(', ')}`
+        await client.query(query, values)
+    } finally {
+        await client.end()
+    }
+
+    return items.length
+}
+
+module.exports = insertBatch