Vatsalya-singhi

import { Injectable, NestMiddleware } from '@nestjs/common';
import { Request, Response, NextFunction } from 'express';

@Injectable()
export class LoggerMiddleware implements NestMiddleware {
  use(req: Request, res: Response, next: NextFunction) {
    console.log(`[${new Date().toISOString()}] ${req.method} ${req.url}`);
    next(); // Pass control to the next handler
  }
}

Vatsalya-singhi

import { Module } from '@nestjs/common';
import { UsersController } from './users.controller';
import { UsersService } from './users.service';

@Module({
  controllers: [UsersController], // Registers the controller
  providers: [UsersService], // Registers the service
  exports: [UsersService], // Allows other modules to use UsersService
  imports: []
})

Vatsalya-singhi

// Users Service (Provides Business Logic)
import { Injectable } from '@nestjs/common';

// injectables include wide range of configurations such as when and how to initialise the provider
@Injectable()
export class UsersService {
  private users = ['Alice', 'Bob', 'Charlie'];

  findAll(): string[] {
    return this.users;

Vatsalya-singhi

import { Controller, Get } from '@nestjs/common';

@Controller('users') // Base route: /users
export class UsersController {
  @Get() // Handles GET /users
  findAll(): string {
    return 'This action returns all users';
  }
}

Vatsalya-singhi

// security
// security
app.use(helmet());
app.disable('x-powered-by');
const limiter = rateLimit({
    windowMs: 15 * 60 * 1000, // 15 minutes
    limit: 100, // Limit each IP to 100 requests per `window` (here, per 15 minutes).
    message: 'Too many requests from this IP, please try again later.',
    standardHeaders: 'draft-7', // draft-6: `RateLimit-*` headers; draft-7: combined `RateLimit` header
    legacyHeaders: false, // Disable the `X-RateLimit-*` headers.

Vatsalya-singhi

mqtt_sub.js
// When a message is received
client.on('message', (receivedTopic, message) => {
    console.log('Received message on topic:', receivedTopic.toString());
    // console.log('Message:', message.toString());

    // Call Kafka's produceMessage function with received MQTT message
    produceKafkaMessage(kafka_topic, message.toString())
        .then(() => {
            console.log('Message published to Kafka');

Vatsalya-singhi

// MQTT PUB CODE
const publish_led_status = (value) => {
    // Publish the message to the specified topic
    client.publish(topic, String(value), (err) => {
        if (!err) {
            console.log('Message published:', value);
        }
        setLedStatus(value);
    });
};

Vatsalya-singhi

public onicecandidateListener(event: RTCPeerConnectionIceEvent, id: string) {
        if (event.candidate && event.candidate.sdpMid && event.candidate.sdpMLineIndex) {
            this.socket.sendCandidate(id, event.candidate);
        } else {
            console.log('candidate not sent');
        }
}

Vatsalya-singhi

public candidateListen() {
        this.socket.candidateListen()
            .pipe(takeWhile(() => this.alive))
            .subscribe((data) => {
                let id: string = data.id;
                let candidate: RTCIceCandidate = new RTCIceCandidate(data.candidate);

                if (!this.peerConnections[id] || this.peerConnections[id] == null) {
                    this.peerConnections[id] = new RTCPeerConnection(this.connectionConfig);
                }

Vatsalya-singhi

public offerListener() {
        this.socket.offerListen()
            .pipe(takeWhile(() => this.alive))
            .subscribe(async (data) => {
                // receive user id and peer offer
                let id: string = data.id;
                let offer: RTCSessionDescription = data.offer;

                if (!this.peerConnections[id] || this.peerConnections[id] == null) {
                    this.peerConnections[id] = new RTCPeerConnection(this.connectionConfig);