Express.js & PostgreSQL CRUD API

Objective

• Create a simple Express.js API that connects to a PostgreSQL database and performs basic database operations (CRUD - Create, Read, Update, Delete).

Prerequisites

• Node.js installed
• PostgreSQL installed and running

Setup

1. Clone the repository.
2. Create database:

   CREATE DATABASE your_db_name;
   \c your_db_name
   \i init_db.sql

3. Install dependencies:

   npm install express pg

4. Configure environment: Create a .env file or set env vars:

   PG_USER=your_db_user
   PG_PASSWORD=your_db_password
   PG_DATABASE=your_db_name
   PG_HOST=localhost
   PG_PORT=5432

5. Run server:

   node server.js

API Endpoints

Method	Endpoint	Description
GET	/users	Retrieve all users
GET	/users/:id	Retrieve user by ID
POST	/users	Create a new user
PUT	/users/:id	Update a user by ID
DELETE	/users/:id	Delete a user by ID

Example Requests

# Create user
curl -X POST http://localhost:3000/users \
  -H 'Content-Type: application/json' \
  -d '{"name":"Alice","email":"alice@example.com","age":30}'

# Get all users
curl http://localhost:3000/users