Tekana-eWallet Backend Revamp

Introduction

This project aims to rebuild the back-end solution for the legacy Tekana-eWallet application, serving over 1 million customers worldwide. This README provides an overview of the strategy, technology stack, code source, and features implemented in the revamped back-end system.

Implented Deployment Architecture

Strategy

My strategy for development Tekana-e-Wallet encompasses the following steps:

• Project Initiation: I put myself in cross-functional teams position like:
  • including Business,
  • UI/UX,
  • front-end, and
  • product owners.
• Technology Stack:
  • Node js Engine
  • Express/Typescrity Framework
  • PostgresSQL Database
  • Sequelize ORM
  • Docker for Containilization
• Development Process:
  • Modularity My Codes are grouped in well structured folders.
  • Coding Standards Are in place
  • Clear Function and Class Definitions I used standard to name classes and functions with appropriet naming convention.
  • Documentation All my endpoints are documented using swagger ui
• Testing and Quality Assurance:
  • My code are setted up to be tested using Jest framework
• Deployment:
  • Onrender Render is a unified cloud to build and run all your apps

Code Source

The back-end source code for Tekana-eWallet is hosted on https://github.com/Nkbtemmy/tekana-e-wallet. Below are key features that showcase the code design and functionality:

Features

• Customer Registration: Enables customers to register and login in the e-wallet system.
• Wallet Creation: Supports the creation of wallets for registered customers.
• Customer Details: Provides the ability to read customer details.
• Transaction Management: Facilitates creating and reading transactions.

Database Design

The database design is optimized for high performance with considerations for indexing, normalization, partitioning, and data types. And i choose to use PostgresSQL database because of its benefits over other SQL databases.

Entity Relationship Diagram(ERD)

API Documentation and Design

APIs are well-documented and designed with best practices, including clear naming conventions, proper HTTP methods, error handling, versioning, and security measures. https://tekana-e-wallet.onrender.com/api-docs/

Creativity and Innovation

I have incorporated innovative solutions and out-of-the-box thinking to address unique challenges in the e-wallet domain.

• I Did also implement auto scaling using node js feature of utilizing server's processorsso that we will have more than one application instance running on server.

Running the Code

The code is ready to run with minimal configuration. To get started, follow these steps:

1. Clone the repository.
2. Enter in repository folder
3. Install dependencies by using yarn install or npm install in your terminal
4. Configure your developmet environment by creating .env file and copy paste from .env.example.
5. Make sure you have created postgres database so that you could use correct credentials.
6. First run yarn db:migration or npm run db:migration.
7. Run the application with the scripts specified on next line.

Good way to test this application with less requirements is to run * make start * while docker is up and running, because it will use images from docker compose and takes the tester shorter time to run without additional installations

Runnable Scripts

• dev: Runs the project in development mode with automatic server restarts on file changes using nodemon.
• ts:dev: Runs TypeScript code in development with automatic restarts, directory watching, and specifying the entry file using ts-node-dev.
• start: Starts the application in production mode by executing the compiled JavaScript code.
• build: Compiles TypeScript code into JavaScript using the TypeScript compiler (tsc).
• clean: Removes the build directory or any build artifacts using rimraf.
• prebuild: Cleans up existing build artifacts before starting the build process.
• format: Automatically formats the code using Prettier.
• test: Runs unit tests with Jest, specifying the port, using a Jest configuration file, and including options for open handle detection and forced exit.
• test:coverage: Runs unit tests with Jest and generates code coverage reports.
• db:migrate: Executes database migrations using Sequelize.
• db:seed: Seeds the database with initial data using Sequelize.
• db:unseed: Unseeds the database by undoing all previously seeded data using Sequelize.
• db:migrate:undo: Undoes all previous database migrations using Sequelize.
• db:reset: Resets the database by undoing migrations, reapplying migrations, and seeding using npm scripts.
• db:hard:reset: Performs a comprehensive database reset, including dropping, creating, migrating, and seeding the database using npm scripts.
• db:create: Creates the database using Sequelize.
• db:make:migration: Generates a new migration file using Sequelize with the specified name.
• db:drop: Drops the database using Sequelize.

Submission

The source code is available on https://github.com/Nkbtemmy/tekana-e-walletas public repository and will be accessible to anyone want to.

Proposed architecture

Proposed Architecture Details

In my e-wallet application, i have proposal of implementing a robust microservices architecture to provide the flexibility, scalability, and maintainability required for a modern financial platform. At the core of this architecture, I will employ Apache Kafka for asynchronous communication between microservices, ensuring real-time transaction processing and seamless interaction between the components. The microservices are organized into key areas, including customer management, wallet creation, and transaction recording, each responsible for distinct aspects of the application's functionality. This modular approach enhances the system's agility and maintainability, this will allow me to scale specific components independently to meet varying demands. With a combination of containerization, centralized authentication and authorization, data caching like using redis, and comprehensive testing, the architecture will be designed to offer a secure, high-performance, and responsive e-wallet solution.