Wallet API

Preface

The motivation was to create a scalable wallet transaction system that allows users to pay each other with their phone numbers. The API has been tested for 100 concurrent users, performing transactions simultaneously with the help of postman. All db transactions are acid compliant and the database deadlocks problem is solved by prioritizing debit and credit requests on the basis of the phone number of the users involved.

Introduction

This is an API that maintains user wallets and allows inter wallet transactions between users. The transactions are made possible with acid compliant db transactions. To try the API yourself click here.

Getting started

1. Clone the repo in desired directory:

   git clone https://github.com/Lakshya-Kapoor/E-wallet-APIs.git

2. Install dependencies:

   npm install

3. PostgreSQL setup:

   • Install postgreSQL and create a database to store the tables:

   • Now set following environment variables for db connection:

     • DB_USER
     • DB_HOST
     • DB_NAME
     • DB_PASSWORD
     • DB_PORT

   • Run all the commands inside the /utils/tableSchema.sql file to create all the tables

4. Setup following environment variables for jwt auth

   • ACCESS_TOKEN_SECRET
   • REFRESH_TOKEN_SECRET

5. Run the server:

   • Trying out api

     npm run start

   • For devlopment

     npm run dev

API reference

Auth

• POST /auth/signup: To store user info in database
• POST /auth/login: To generate JWT token

User

• GET /user/balance: Get user wallet balance
• POST /user/pay: Pay another user
• GET /user/transactions: Get user transactions

Admin

• GET /admin/users: Get data of all users
• GET /admin/users/:phone_no: Get data of particular user
• GET /admin/transactions/:phone_no: Get all transactions of a user
• GET /admin/verify_transactions/:phone_no: Verify correctness of all the transactions