Configuration

Part of the REST APIs section of Coddy's Node.js journey. Lesson 16 of 18.

On your laptop the server listens on port 3000. A hosting service starts it with node server.js and chooses the port itself, passing it in the environment as PORT. A process manager there restarts the server when it crashes and calls a route like GET /health to see that it is up.

// MAX_UPLOAD_MB=5 node server.js
const maxUpload = Number(process.env.MAX_UPLOAD_MB ?? 2);
const shopName = process.env.SHOP_NAME ?? 'My Shop';

Every value in process.env is a string, and '5' + 1 is '51', so convert numbers with Number. Read the settings in one file, config.js, and import them everywhere else, so nothing else touches process.env.

Challenge

Easy

In config.js, read port from PORT and pageSize from PAGE_SIZE, as numbers, keeping the defaults.
Listen on config.port, printing Task tracker API on port <port>; the default limit is config.pageSize.
GET /health answers { "status": "ok" }.

This lesson runs with PORT=8080 and PAGE_SIZE=2. Send GET /api/v1/tasks, then GET /health.

Try it yourself

// The settings that change between your laptop and a server.
// Read each one from process.env, keeping these values as defaults.
export const config = {
    port: 3000,
    pageSize: 10,
};