#12 Creating Routes in Node JS | Fundamentals of NODE JS | A Complete NODE JS Course

Summary

In this tutorial, the instructor demonstrates how to implement basic routing in a Node.js application. The video explains how to differentiate responses based on the URL entered by the user, such as for home, about, and contact pages. The script shows how to extract the URL from the request and return corresponding responses. Additionally, a fallback route is introduced to handle unrecognized URLs, returning a 404 error page. The lesson concludes by hinting at the next step, which involves sending HTML responses instead of text. This session serves as a solid introduction to Node.js routing basics.

Takeaways

• 😀 The script introduces the concept of routing in a Node.js application, explaining how it helps manage different page requests.
• 😀 Initially, all URLs typed in the address bar return the same response due to a lack of URL handling in the server code.
• 😀 The core idea is to extract the URL from the incoming request and return different responses based on the URL path.
• 😀 The 'request.url' property is used to capture the URL entered by the user after the root URL, which helps determine the route.
• 😀 A new 'path' variable is created to store the URL from the request and then is used to generate a dynamic response for the user.
• 😀 A simple routing mechanism is implemented using 'if' statements to check specific paths like '/', '/home', '/about', and '/contact'.
• 😀 For each path, the server sends a specific response, such as 'You are in home page' for the root URL or 'You are in about page' for '/about'.
• 😀 If an unhandled route is requested, such as '/products', the server enters an error state and the page remains unresponsive.
• 😀 A fallback route is added to handle unknown paths, returning a '404 Page Not Found' message to the user.
• 😀 The script ends by discussing the next lecture, where the user will learn how to send HTML responses instead of plain text for each route.

Q & A

What is the main topic of the lecture?

The main topic of the lecture is implementing simple routing in a Node.js application.

Why does the current Node.js server always return the same response regardless of the URL?

The server always returns the same response because the callback function in the server does not check the URL and simply returns a default response for every request.

What is the purpose of extracting the URL from the request object?

The purpose of extracting the URL is to identify what the user has typed in the address bar, so the server can send a different response based on that URL.

How is the path of the URL extracted in the Node.js application?

The path is extracted from the request object using `request.url`. This value contains the portion of the URL typed after the root URL.

What does the code `request.url` return?

The code `request.url` returns the value typed by the user after the root URL, such as '/home', '/about', or '/contact'.

How does the Node.js server determine which response to send for different URLs?

The server checks the value of `request.url` (or the 'path' variable) and sends a specific response based on that value, such as 'You are in home page' for the root URL or '/home'.

What happens if a user types a URL that is not handled by the server?

If the user types a URL that is not handled, the server would hang and not return any response unless a fallback route is defined.

How can we handle URLs that are not specifically routed in the server?

To handle unrecognized URLs, a fallback route can be defined that returns a 404 error response, such as 'Page not found'.

What is the purpose of using `else` in the routing logic?

The `else` part is used to define the fallback route for any URL that doesn't match the pre-defined routes, ensuring that the server doesn't hang and returns a 404 error instead.

What would happen if the `else` fallback route is not implemented in the server?

Without the `else` fallback route, the server would fail to respond to any URL that is not specifically handled, causing the page to hang and continuously load.