Kube Credential

An assignment for a full stack microservice based project

---

Tech Stack

Backend: Node.js, TypeScript, Express, Prisma, SQLite, Jest
Frontend: React, TypeScript, Vite, Tailwind CSS, shadcn/ui, Axios
DevOps: Docker, Kubernetes, AWS EC2

---

Video

https://www.loom.com/share/35ad0a93d92b43cb89907f8afe19acd2

Screenshots

1. Credential issuance success

2. Duplicate credentials

3. Credential verification success

kubectl get pods

Hosting

---

Architecture Overview

React Frontend (Vite + TypeScript)
         ↓                    ↓
Issuance Service      Verification Service
(Express + Prisma)    (Express + Prisma)
         ↓                    ↓
SQLite Database       SQLite Database

Two independent microservices running in separate Kubernetes pods, each with its own database. Frontend communicates with both services via REST APIs.

---

Project Structure

zupple/
├── client/                    # React frontend (Vite + TypeScript + Tailwind)
├── services/
│   ├── issuance/             # Credential issuance microservice
│   │   ├── src/
│   │   │   ├── api/issue/    # Controllers, services, routes
│   │   │   ├── config/       # Config & database setup
│   │   │   └── tests/        # Jest unit tests
│   │   ├── prisma/           # Database schema & migrations
│   │   └── Dockerfile
│   └── verification/         # Credential verification microservice
│       ├── src/
│       │   ├── api/verify/   # Controllers, services, routes
│       │   ├── config/       # Config & database setup
│       │   └── tests/        # Jest unit tests
│       ├── prisma/           # Database schema & migrations
│       └── Dockerfile
└── k8s/                       # Kubernetes deployment manifests

---

Design Decisions

1. Database: SQLite with Prisma

• Lightweight, zero-config, perfect for free-tier deployment
• Prisma provides type-safe queries and automatic migrations
• Each service has its own database

2. Credential Hashing

• Credentials are SHA-256 hashed before storage
• Hash uniqueness constraint prevents duplicate issuance
• Enables fast duplicate detection without comparing full JSON

3. Worker Identification

• Worker ID injected via Kubernetes (metadata.name)
• Each pod automatically gets unique identifier
• Stored with credentials for traceability

4. Service Independence

• Each microservice is independently deployable and scalable
• Separate databases ensure no shared state
• RESTful APIs for communication (Webhook)

---

Setup & Running

Local Development

# Issuance Service
cd services/issuance
npm install
npx prisma generate
npm run dev  # Runs on port 3000

# Verification Service
cd services/verification
npm install
npx prisma generate
npm run dev  # Runs on port 3001

# Frontend
cd client
npm install
npm run dev  # Runs on port 5173

Docker Build

# Build images
docker build -t <username>/issuance-service:1.0 services/issuance
docker build -t <username>/verification-service:1.0 services/verification

# Push to registry
docker push <username>/issuance-service:1.0
docker push <username>/verification-service:1.0

Kubernetes Deployment

# Deploy services
kubectl apply -f k8s/issuance-deployment.yaml
kubectl apply -f k8s/issuance-service.yaml
kubectl apply -f k8s/verification-deployment.yaml
kubectl apply -f k8s/verification-service.yaml

# Check status
kubectl get pods
kubectl get services

---

Testing

• AI Generated Unit Tests

# Issuance service tests
cd services/issuance
npm test

# Verification service tests
cd services/verification
npm test

---

API Endpoints

Issuance Service - POST /api/issue

Verification Service - POST /api/verify

---

Assumptions

1. SQLite is sufficient - Production would use PostgreSQL for better concurrency
2. No authentication - Production would implement JWT based auth
3. Flexible credential schema - Any valid JSON accepted as credential
4. CORS enabled for all origins - Production would whitelist specific domains
5. No data expiration - Credentials stored indefinitely
6. Hash-based duplicate detection - Same JSON content = duplicate credential
7. Services scale independently - Each maintains its own database

---