add background queues to handle heavy task

Author: NoB0T21

backend/Dockerfile

@@ -15,4 +15,4 @@ RUN npm run build
 EXPOSE 3000
 
 # Start Redis + Node
-CMD redis-server --daemonize yes && node ./dist/server.js
+CMD redis-server --daemonize yes && npm run start2

backend/package-lock.json

@@ -7,7 +7,9 @@
     "test": "jest",
     "client": " npm run dev --prefix ../frontend",
     "start": "node ./dist/server.js",
+    "worker": "node ./dist/worker.js",
     "dev": "nodemon",
+    "start2": "concurrently \" npm start \" \" npm run worker \"",
     "build": "tsc"
   },
   "author": "Aryan Gawade (NoB0T)",
@@ -23,6 +25,7 @@
     "@types/jsonwebtoken": "^9.0.10",
     "@types/multer": "^1.4.13",
     "@types/node": "^24.0.3",
+    "@types/nodemailer": "^7.0.9",
     "@types/uuid4": "^2.0.3",
     "concurrently": "^9.1.2",
     "dotenv-cli": "^8.0.0",
@@ -47,6 +50,7 @@
     "jsonwebtoken": "^9.0.2",
     "mongoose": "^8.16.0",
     "multer": "^2.0.1",
+    "nodemailer": "^8.0.0",
     "uuid4": "^2.0.3",
     "ws": "^8.18.2"
   }

backend/package.json

@@ -5,6 +5,7 @@ import userModel  from '../Models/user.model'
 import jwt from 'jsonwebtoken'
 import uuid4 from "uuid4"
 import supabase from "../Db/supabase"
+import redis from "../Db/redis";
 
 const client = new OAuth2Client(process.env.GOOGLE_ID)
 
@@ -27,6 +28,13 @@ export const register = async (request: Request, response: any) => {
     try {
         const existingUsers = await findUser({email})
         if(existingUsers){
+            const job = {
+                type: "sendEmail",
+                to: email,
+                subject: 'Wellcome back',
+            };
+            console.log('job added')
+            await redis.lpush("jobs", JSON.stringify(job))
             return response.status(202).json({
                 message: "email already exists, Please Sign-in",
                 user: existingUsers,
@@ -95,7 +103,6 @@ export const register = async (request: Request, response: any) => {
 }
 
 export const login = async (request: Request, response:any) => {
-    console.log(request.body)
     const {email, password} = request.body
     if(!email||!password){
         return response.status(400).json({
@@ -118,6 +125,12 @@ export const login = async (request: Request, response:any) => {
                 success: false,
         })}
         const token = await user.generateToken()
+        const job = {
+            type: "sendEmail",
+            to: email,
+            subject: 'Wellcome back',
+        };
+        await redis.lpush("jobs", JSON.stringify(job));
         return response.status(201).json({
             message: "User login successfully",
             user,

backend/src/controller/user.controller.ts

@@ -0,0 +1,57 @@
+import Redis from "ioredis";
+import nodemailer from "nodemailer";
+import dotenv from "dotenv"
+dotenv.config();
+
+const transporter = nodemailer.createTransport({
+    host: "smtp.gmail.com",
+    port: 465,
+    secure: true,
+    auth: {
+        user: process.env.EMAIL_USER,
+        pass: process.env.EMAIL_PASS,
+    },
+});
+const redis = new Redis(process.env.REDIS_URL||'');
+
+async function sendEmail(to: string) {
+  await transporter.sendMail({
+    from: process.env.EMAIL_USER,
+    to,
+    subject: "Welcome back",
+    text: "Hello Aryan 👋",
+  });
+}
+
+async function startWorker() {
+  console.log("Worker started...");
+
+  while (true) {
+    const result = await redis.brpop("jobs", 0);
+
+    if (!result) continue;
+
+    const [, jobString] = result;
+    const job = JSON.parse(jobString);
+
+    await processJob(job);
+  }
+}
+
+async function processJob(job: any) {
+    console.log("Processing:", job);
+    console.log(process.env.EMAIL_PASS)
+    console.log(process.env.EMAIL_USER)
+    try {
+        console.log("Sending email...");
+
+        await sendEmail(job.to);
+
+        console.log("Email sent successfully!");
+    } catch (err) {
+        console.error("Email failed:", err);
+    }
+    await new Promise(r => setTimeout(r, 2000));
+}
+
+startWorker();