MERN Pay App

Complete fullstack payment application with error handling and JWT authentication.

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Features

• Users can login
• Users can signup
• Users can logout
• Users can update profile
• Users can delete profile
• Users can send money to other users

Technologies Used

• Node.js
• Express
• MongoDB
• Mongoose
• JWT
• React
• React Router DOM
• Tailwind CSS

How to use

1. To start the server:

   i. Create .env file and store the env variables.

   ii. Use this format:

   JWT_SECRET = <"YOUR JWT SECRET">
   MONGO_URI = <"YOUR MONGO URI">

   iii. Run the server:

   cd backend
   npm install
   npm run start

   Server will be running on http://localhost:5000

2. To start the frontend:

You should add your backend url in the BASE_URL variable in api.jsx.

cd frontend
npm install
npm run dev

Frontend will be running on http://localhost:5173

Notes & Troubleshooting

This App uses MongoDB's transaction feature, for which the database should be a replica set. It will run smoothly for a MongoDB Atlas instance. But for a local MongoDB instance, you may need to use the rs.initiate() thing. Google about that issue before running it locally.

Your MongoDB version should be 4.0+

For reference: this thing worked for me.

I created 3 replica set dbs.

For creating dbs:

mongod --port 27018 --dbpath "C:\Program Files\MongoDB\Server\7.0\db1" --replSet rs1
mongod --port 27019 --dbpath "C:\Program Files\MongoDB\Server\7.0\db2" --replSet rs1
mongod --port 27020 --dbpath "C:\Program Files\MongoDB\Server\7.0\db3" --replSet rs1

For initiating the replica dbs:

rs.initiate({
  _id: "rs1",
  members: [
    { _id: 0, host: "localhost:27018" },
    { _id: 1, host: "localhost:27019" },
    { _id: 2, host: "localhost:27020" },
  ],
});