EMCP Baseline NestJS Backend

A production‑ready NestJS backend service with Docker, Docker Compose

Description

This project is a baseline NestJS backend service designed for cloud‑native environments. It provides a solid starting point that includes:

• A modular, TypeScript‑based NestJS server

• Docker and Docker Compose configuration for local development

Prerequisites

• Node.js (v18 or higher recommended)

• Docker

• Docker Compose

Developer Home Test 🚀

Welcome new developers! Complete this ping-pong service challenge to demonstrate your understanding of the tech stack.

Challenge Overview

Build a real-time ping-pong service that demonstrates:

• RESTful API endpoints

• Redis streams for message queuing

• WebSocket connections for real-time communication

• Client-side real-time updates

Requirements

Backend Implementation

1. Ping Endpoint: Create a POST endpoint /api/ping that:

   • Accepts a "ping" message from clients

   • Writes the message to a Redis stream

   • Returns acknowledgment to the client

2. Redis Stream Processing: Implement a background service that:

   • Listens to the Redis stream for new ping messages

   • Processes each message and transforms it to "pong"

   • Broadcasts the "pong" message to all connected WebSocket clients

3. WebSocket Gateway: Create a WebSocket gateway that:

   • Accepts client connections

   • Broadcasts "pong" messages to all connected clients

   • Handles client connect/disconnect events

Frontend Implementation

1. Client Application: Build a simple client (React preferred) that:

   • Has a button to send "ping" requests to the server

   • Connects to the WebSocket to receive "pong" messages

   • Displays received "pong" messages in real-time

Technical Requirements

• Local Development Only: No need for multi-node considerations

• Docker Compose: All services must run via docker-compose up

• Dependencies: Include Redis in your docker-compose setup

• Real-time: Use WebSockets for client-server communication

• Message Queue: Use Redis streams (not pub/sub)

Evaluation Criteria

• ✅ Code quality and organization

• ✅ Proper error handling

• ✅ Docker setup works out of the box

• ✅ Real-time functionality works as described

• ✅ Clean and intuitive client interface

• ✅ Documentation and comments

Deliverables

1. Updated NestJS backend with ping-pong service

2. Client application (React or any framework)

3. Updated docker-compose.yml with Redis

4. Brief documentation explaining your implementation choices

Submission

1. Click on "Use this template" to create a new repository

2. Commit your changes

3. Push your changes to your new repository

4. Send an email - [email protected] with a link

Support

If you encounter issues during the home test or have questions about the setup, please:

1. Email - [email protected]

2. Feel free to use any AI, but do not share the entire repo with AI

Good luck with the home test! Happy hacking 🎯