require('dotenv').config(): Load environment variables from a .env file. const express = require('express'): Import the Express module. const passport = require('passport'): Import the Passport module for authentication. const GoogleStrategy = require('passport-google-oauth20').Strategy: Import the Google OAuth 2.0 strategy for Passport. const session = require('express-session'): Import the session middleware. const { Sequelize, DataTypes } = require('sequelize'): Import Sequelize and DataTypes for ORM. const Intercom = require('intercom-client'): Import the Intercom client library. const app = express(): Create an instance of an Express application. app.use(express.json()): Middleware to parse JSON bodies. const sequelize = new Sequelize(process.env.MYSQL_URI): Create a new Sequelize instance using the MySQL URI from environment variables. const User = sequelize.define('User', { ... }): Define the User model with the specified attributes. const ServiceRequest = sequelize.define('ServiceRequest', { ... }): Define the ServiceRequest model with the specified attributes. sequelize.sync(): Sync all defined models with the database. const intercomClient = new Intercom.Client({ token: process.env.INTERCOM_ACCESS_TOKEN }): Create a new Intercom client instance with the access token from environment variables. passport.use(new GoogleStrategy({ ... }, async (token, tokenSecret, profile, done) => { ... })): Configure Passport to use the Google OAuth 2.0 strategy. let user = await User.findOne({ where: { googleId: profile.id } }): Find a user by Google ID. if (!user) { user = await User.create({ ... }) }: Create a new user if one doesn't exist. passport.serializeUser((user, done) => { done(null, user.id); }): Serialize user information into the session. passport.deserializeUser(async (id, done) => { const user = await User.findByPk(id); done(null, user); }): Deserialize user information from the session. app.use(session({ secret: 'secret', resave: false, saveUninitialized: false })): Set up session middleware. app.use(passport.initialize()): Initialize Passport middleware. app.use(passport.session()): Enable session support for Passport. app.get('/auth/google', passport.authenticate('google', { scope: ['profile', 'email'] })): Define a route to start the Google OAuth flow. app.get('/auth/google/callback', passport.authenticate('google', { failureRedirect: '/' }), (req, res) => { res.redirect('/'); }): Define a route to handle the OAuth callback. const isAuthenticated = (req, res, next) => { if (req.isAuthenticated()) { return next(); } res.redirect('/auth/google'); }: Middleware to check if the user is authenticated. app.post('/api/service-request', isAuthenticated, async (req, res) => { ... }): Define a route to submit customer service requests. const intercomResponse = await intercomClient.messages.create({ ... }): Send the customer service request to Intercom. const serviceRequest = await ServiceRequest.create({ ... }): Create a new service request record in the database. app.get('/api/service-requests/ ', isAuthenticated, async (req, res) => { ... }): Define a route to retrieve customer service requests by category. const requests = await ServiceRequest.findAll({ where: { userId: req.user.id, category: req.params.category } }): Fetch service requests from the database. const PORT = process.env.PORT || 5000: Define the server port. app.listen(PORT, () => console.log(Server running on port ${PORT})): Start the Express server.

front end:

import React, { useState } from 'react': Import React and useState hook. import { BrowserRouter as Router, Route, Switch, Redirect } from 'react-router-dom': Import Router components from react-router-dom. import axios from 'axios': Import axios for making HTTP requests. import GoogleLogin from 'react-google-login': Import GoogleLogin component. App Component:

const [user, setUser] = useState(null): State to store user information. const [requests, setRequests] = useState([]): State to store customer service requests. const handleLogin = async (response) => { ... }: Function to handle Google login. const { tokenId } = response: Extract tokenId from response. const result = await axios.post('/auth/google', { id_token: tokenId }): Send tokenId to backend for authentication. setUser(result.data): Store user data in state. const fetchRequests = async (category) => { ... }: Function to fetch customer service requests by category. const result = await axios.get(/api/service-requests/${category}): Make a GET request to fetch requests. setRequests(result.data): Store requests in state.