App with all functionalities completely working

README.md

@@ -1,2 +1,2 @@
 
-## Build a basic version of PayTM
+## Build a basic version of Easy Pay App

backend/config.js

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+module.exports = {
+	JWT_SECRET: "I_KNOW_YOUR_SECRET",
+};

backend/db.js

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+const mongoose = require("mongoose");
+const bcrypt = require("bcrypt");
+
+main().catch((err) => console.log(err));
+
+async function main() {
+	await mongoose.connect(
+		"mongodb+srv://dtsri:[email protected]/users"
+	);
+}
+
+//creating a schema
+const UserSchema = new mongoose.Schema({
+	username: {
+		type: String,
+		required: true,
+		unique: true,
+		trim: true,
+		lowercase: true,
+		minLength: 3,
+		maxLength: 30,
+	},
+	password: {
+		type: String,
+		required: true,
+		minLength: 6,
+	},
+	firstName: {
+		type: String,
+		required: true,
+		trim: true,
+		maxLength: 25,
+	},
+	lastName: {
+		type: String,
+		required: true,
+		trim: true,
+		maxLength: 25,
+	},
+});
+
+// Method to generate a hash from plain text
+UserSchema.methods.createHash = async function (plainTextPassword) {
+	// Hashing user's salt and password with 10 iterations,
+	const saltRounds = 10;
+
+	// First method to generate a salt and then create hash
+	const salt = await bcrypt.genSalt(saltRounds);
+
+	//generates the hashPassword
+	return await bcrypt.hash(plainTextPassword, salt);
+};
+
+//For validation, get the password from DB (this.password --> hashPassword) and compare it to the input Password provided by the client
+//note: we dont implement this method
+UserSchema.methods.validatePassword = async function (candidatePassword) {
+	//returns a boolean indicating if passwords matches or not
+	return await bcrypt.compare(candidatePassword, this.password);
+};
+
+//creating a User Model aka creating a class
+const User = mongoose.model("USER", UserSchema);
+
+const AccountSchema = new mongoose.Schema({
+	userId: {
+		type: mongoose.Schema.Types.ObjectId,
+		ref: "User", //this refferring to the document of the User Model
+		//for value we have to just metnion ref:user._id
+		required: true,
+	},
+	balance: {
+		type: Number,
+		required: true,
+	},
+});
+
+const Account = mongoose.model("Account", AccountSchema);
+
+module.exports = {
+	User,
+	Account,
+};

backend/index.js

@@ -1,3 +1,15 @@
 const express = require("express");
+const cors = require("cors");
+const rootRouter = require("./routes/index");
 
+const app = express();
 
+app.use(cors()); //enabling the cross origing resoure sharing policy since frontend and backend are two differnt origins,
+//frontend will request from backend.
+
+app.use(express.json()); //parses the JSON  //request body-parser
+app.use("/api/v1", rootRouter);
+
+app.listen(3000, () => {
+	console.log(`server is up and running`);
+});

backend/middleware.js

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+const jwt = require("jsonwebtoken");
+const { JWT_SECRET } = require("./config");
+
+//this function is mainly to indentify the person via jsonwebtoken
+
+async function authMiddleware(req, res, next) {
+	const authHeader = req.headers?.authorization;
+
+	console.log(authHeader);
+
+	if (!authHeader || !authHeader.startsWith("Bearer")) {
+		res.status(403).json({
+			message: "There is an issue with authorization headers",
+		});
+	}
+
+	const token = authHeader.split(" ")[1];
+	jwt.verify(token, JWT_SECRET, (err, payload) => {
+		if (err) {
+			res.status(403).json({
+				message: "Please check the login credentials",
+			});
+		} else {
+			const userId = payload.userId;
+
+			//putting the userID in the request body, so that it can be used by next callback function
+			//in a route, you can add multiple callback functions
+			req.userId = userId;
+
+			next();
+		}
+	});
+}
+
+module.exports = {
+	authMiddleware,
+};