Create Server in node under the hood

The image appears to be a conceptual diagram explaining how a Node.js server processes incoming HTTP requests.
Here's a description of the components and their relationships as depicted in the diagram:

Main Components:

1. Node.js Server Code:

   • The code snippet demonstrates setting up an HTTP server in Node.js:

    const doOnIncoming = (req, res) => {};
    const doOnError = (error, data) => {};
   
    const server = http.createServer();
   
    server.listen(80);
    server.on('request', doOnIncoming);
    server.on('error', doOnError);
   

• Functions:
  • doOnIncoming: Handles incoming requests.
  • doOnError: Handles server errors.
• server.listen(80): Starts the server to listen on port 80.
• Event handlers:
  • 'request': Triggers the doOnIncoming function.
  • 'error': Triggers the doOnError function.

1. HTTP Request Flow:

   • A request (e.g., http://twitter/3) is sent to the server.
   • It is received as a Buffer through a socket connection.

2. Libuv and Computer Features:

   • Libuv acts as the bridge between Node.js and system-level operations:
     • Handles networking and file system tasks.
   • Manages asynchronous I/O operations.

3. Node.js/C++ Features:

   • Auto-added arguments:
     • req (Request Object): Contains details like body and header.
     • res (Response Object): Provides methods such as send(), status(), and json().
   • Auto-executed functions:
     • doOnIncoming: Processes the request and sends a response.
     • doOnError: Handles and logs errors.

4. Storage Layer:

   • Contains definitions for functions and server-related methods:
     • doOnIncoming
     • doOnError
     • server object (with listen and on methods).

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Request Flow Overview:

1. A HTTP request enters the system.
2. The socket is opened to process the request With Port (80/443)
3. The request passes through Libuv, which interacts with the system's networking and file system capabilities.
4. Node.js handles the request using predefined functions (doOnIncoming and doOnError) and sends a response back.

This diagram illustrates the interplay between JavaScript, Node.js, and the system's underlying C++ features, providing a clear picture of how Node.js processes requests at a low level.

Reference:-
https://frontendmasters.com/courses/servers-node-js/