Building a RESTful API with benhall/express-demo

Scenario:

You aim to create a RESTful API using Express and the benhall/express-demo project as a foundation. This API will handle various HTTP methods and use middleware for request validation and response formatting.

Solution:

Familiarize yourself with the project structure: The project consists of several files and directories, including routes, views, and middleware.

routes/: Contains Express route files for handling different API endpoints.
views/: Contains Handlebars templates for rendering views.
public/: Static files (CSS, images) that can be accessed directly.
app.js: The main entry point for the Express application.
Dockerfile: Used for building Docker images.
docker-compose.yml: Configures Docker services.
nodemon.json: Configures the development server using nodemon.
package.json: Manages project dependencies.

Define routes: Create a new file in the routes directory, e.g., routes/users.js. In this file, define routes for handling user-related API endpoints using Express Router.

const express = require('express');
const router = express.Router();

// Define routes and handlers for each route here

module.exports = router;

Handle HTTP methods: Add routes and their corresponding handlers for each HTTP method (GET, POST, PUT, DELETE). For example, to handle a GET request for retrieving a user, add the following code to the users.js file:

router.get('/users/:id', (req, res) => {
// Your logic for retrieving a user goes here
res.json(user);
});

Use middleware for request validation: Install a middleware package like express-validator for request validation. Add the following code to the app.js file to use it:

const express = require('express');
const bodyParser = require('body-parser');
const expressValidator = require('express-validator');

const app = express();

app.use(bodyParser.json());
app.use(expressValidator());

// Add your routes here

// Middleware for handling validation errors
app.use((err, req, res, next) => {
if (err.isJoi) {
return res.status(400).json({ errors: err.details });
}
next();
});

// Start the server
const PORT = process.env.PORT || 3000;
app.listen(PORT, () => {
console.log(`Server is running on port ${PORT}`);
});

Use middleware for response formatting: Install a middleware package like express-response for response formatting. Add the following code to the app.js file to use it:

const express = require('express');
const bodyParser = require('body-parser');
const expressValidator = require('express-validator');
const expressResponse = require('express-response');

const app = express();

app.use(bodyParser.json());
app.use(expressValidator());
app.use(expressResponse());

// Add your routes here

// Start the server
const PORT = process.env.PORT || 3000;
app.listen(PORT, () => {
console.log(`Server is running on port ${PORT}`);
});

Tests:

To verify the API functionality, you can use tools like Postman or REST Assured for testing. Here are some example tests:

Test getting a user:

Send a GET request to /api/users/1
Verify the response status is 200 OK and the response body contains the user data.

Test creating a new user:

Send a POST request to /api/users with a valid user object in the request body
Verify the response status is 201 Created and the response body contains the new user data.

Test updating a user:

Send a PUT request to /api/users/1 with a valid user object in the request body
Verify the response status is 200 OK and the response body contains the updated user data.

Test deleting a user:

Send a DELETE request to /api/users/1
Verify the response status is 204 No Content.

Test invalid request:

Send a request with invalid data (missing required fields, incorrect data types, etc.)
Verify the response status is 400 Bad Request and the response body contains error messages.