🚀 News Aggregator API

A NestJS microservice that aggregates and caches NASA RSS feeds using a clean hexagonal architecture. It automatically synchronizes data, ensures high performance with Redis caching, and exposes a documented REST API.

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🎯 Overview

• Fetches and stores NASA news in PostgreSQL
• Uses Redis for caching and fast responses
• Syncs automatically via cron job
• Provides REST API with Swagger docs
• Fully testable hexagonal architecture (ports & adapters)

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🏗️ Architecture Overview

Scheduler → SyncNewsUseCase → NasaProvider → PostgreSQL
HTTP GET /news → GetNewsUseCase → Redis Cache → PostgreSQL

📊 Data Flow

1️⃣ SYNC Flow (Hourly Cron Job)

Scheduler → SyncNewsUseCase → NasaProviderClient
                                     ↓
                              Fetch XML Feed
                                     ↓
                              Parse with fast-xml-parser
                                     ↓
                              Validate & Create Entities
                                     ↓
                              NewsRepository (Upsert)
                                     ↓
                              PostgreSQL

2️⃣ GET Flow (API Request)

HTTP GET /news?limit=10
         ↓
    NewsController
         ↓
    GetNewsUseCase
         ↓
    Check Redis Cache
         ├─ ✅ HIT: Return cached data (⚡ fast)
         └─ ❌ MISS: Query PostgreSQL → Cache in Redis → Return

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🛠️ Tech Stack

Category	Technology
Framework	NestJS 11 + TypeScript 5
Database	PostgreSQL (Prisma ORM)
Cache	Redis 7
Infra	Docker Compose
Docs	Swagger / OpenAPI
Tests	Jest

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🚀 Getting Started

Prerequisites

• Node.js ≥ 18
• pnpm ≥ 8
• Docker & Docker Compose

Quick Start

git clone https://github.com/annaescalada/news-aggregator-api.git
cd api && pnpm install
make run  # Starts DB, runs migrations, and launches the API

API available at http://localhost:3000 Swagger docs at /docs

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🔐 Environment Variables

DATABASE_URL=postgresql://postgres:postgres@localhost:5432/anna_escalada
REDIS_URL=redis://localhost:6379
NASA_RSS_URL=https://www.nasa.gov/rss/dyn/breaking_news.rss
PORT=3000
NODE_ENV=development

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✨ Features

• 🕒 Hourly sync of NASA RSS feeds
• ⚡ Smart Redis caching for repeated queries
• 🧩 Modular & maintainable architecture
• 🧪 Unit & E2E tests with Jest
• 🐳 Docker-based local setup

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🧪 Testing

pnpm test       # Run all tests
pnpm test:e2e   # Run end-to-end tests
pnpm test:cov   # Generate coverage report

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🧱 Project Structure

api/
├── src/
│   ├── modules/news/
│   │   ├── domain/          # Entities
│   │   ├── application/     # Use cases & ports
│   │   ├── adapters/        # Controllers, schedulers, repos
│   │   └── news.module.ts
│   ├── common/              # Shared services (Prisma, Redis)
│   └── main.ts
└── prisma/                  # DB schema & migrations

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🧰 Development Commands

make up       # Start PostgreSQL & Redis
make migrate  # Run migrations
make dev      # Run NestJS in watch mode
make down     # Stop Docker containers

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📝 License

MIT

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Built using NestJS and Hexagonal Architecture