Next.js API Routes Essentials Quiz Quiz

Explore the fundamentals of Next.js API routes with this quiz designed to assess your understanding of routing, request handling, and response management in serverless environments. Expand your knowledge of how API endpoints work in modern web development using Next.js features and conventions.

1. API Route File Naming

   Which file name will correctly create an API endpoint accessible at /api/messages in a Next.js project?

   1. routes/api/messages.jsx
   2. pages/endpoints/messages.js
   3. api_routes/messages.js
   4. pages/api/messages.js

   Explanation: In Next.js, placing a JavaScript file called messages.js in the pages/api directory generates an API endpoint at /api/messages. The other paths, such as pages/endpoints/messages.js and routes/api/messages.jsx, would not be recognized by the routing system as valid API routes. api_routes/messages.js does not fit the required directory convention for API endpoints.

2. Handling HTTP Methods

   When handling different HTTP methods in a Next.js API route, which approach allows you to respond differently to GET and POST requests?

   1. Set separate files for each method type
   2. Use app.get and app.post functions in the file
   3. Change the file extension to .get.js or .post.js
   4. Check req.method and branch logic accordingly

   Explanation: The recommended way to handle various HTTP methods in a Next.js API route is by checking req.method and using conditional logic for GET, POST, and other requests. app.get and app.post functions are not applicable in this framework. Creating separate files or renaming extensions for each method type is not standard practice in this context.

3. Response Sending in API Routes

   Which function call properly sends a JSON response back to the client from a Next.js API route?

   1. response.jsonSend('Success')
   2. resp.sendData({ message: 'Success' })
   3. res.output({ message: 'Success' })
   4. res.status(200).json({ message: 'Success' })

   Explanation: The correct way to send a JSON response in a Next.js API route is by using res.status(200).json. This sets the status code and sends a properly formatted JSON response. resp.sendData and response.jsonSend are not valid methods, while res.output does not exist, making them incorrect choices.

4. Middleware Usage in API Routes

   What is an appropriate way to implement middleware logic like authentication in a Next.js API route?

   1. Call a separate custom function before sending the response
   2. Inject middleware using the apiMiddleware function
   3. Use a built-in middleware array in the route's export
   4. Add a middleware.js file in the pages/api directory

   Explanation: Creating and calling custom functions within the API handler is the practical method to include authentication or similar middleware logic in Next.js API routes. There are no built-in middleware arrays for API routes; apiMiddleware and adding a middleware.js file in the directory are not recognized approaches by the framework.

5. Default Export Requirement

   What must every Next.js API route file export for the route to function correctly?

   1. An object describing the route configuration
   2. A variable with the API endpoint's URL string
   3. A named export called routeHandler
   4. A default function handling the request and response parameters

   Explanation: API route files require a default export that is a function taking request and response objects to process and return data. Exporting an object, a URL string, or a named export called routeHandler will not work, as the framework specifically looks for a default function export.