Getting Started

Goal

This snapshot advances Circuit Daily by teaching you to create a minimal NestJS app on port 3001.

Every numbered folder is a complete app. Run this stage independently, then compare it with the previous folder.

Prerequisites

Use Node.js 20+, npm, and a terminal. You should recognize TypeScript modules, decorators, and HTTP verbs.

Port 3001 must be free. Copy .env.example before starting database stages.

• Node.js and npm
• A code editor and terminal
• Docker from part 4 onward

Concepts

NestJS boots an Express-backed application with modules, controllers, and dependency injection.

Keep controllers thin: accept input, call services, render Handlebars views. Escape stays on by default in templates.

Walkthrough

Create the AppModule and a root controller that returns JSON, then listen on port 3001.

Read the example, then open the matching snapshot. The repository includes the surrounding setup and error handling.

@Get()
root() {
  return { message: 'Circuit Daily is live' };
}

Run and verify

Enter 01-Getting-Started, install dependencies, copy .env.example when present, and start Nest on port 3001.

Open http://127.0.0.1:3001. Watch the terminal for validation and database errors.

git clone https://github.com/michaeldunga1/fcc-nestjs-blog.git
cd fcc-nestjs-blog/01-Getting-Started
npm install
cp .env.example .env
npm run start:dev

Troubleshooting

If the browser cannot connect, confirm Nest is still running. EADDRINUSE means another process owns 3001.

Missing-module errors usually mean npm install ran in another snapshot. For Postgres failures, confirm Docker and the circuit_NN database name.

• Read the first error first
• Restart after environment changes
• Never commit .env or node_modules

Try this

Add a /health route that returns JSON ok: true.

Test a happy path and one invalid or unauthorized request.

• Make one small change
• Test it in the browser
• Compare with the next snapshot only after it works