What components make up an HTTP request and how do they interact?

An HTTP request consists of several main components:

1. Request Line — contains the request method (GET, POST, etc.), URL, and HTTP protocol version.

2. Headers — a set of key-value pairs that convey meta-information about the request, such as Content-Type, Authorization, User-Agent.

3. Body — an optional part containing data sent by the client to the server (e.g., form data or JSON in POST requests).

4. Empty line — separates headers from the body.

Interaction of components:

• The client forms the request line with the required method and URL.
• Adds necessary headers to describe the request.
• If needed, adds a body with data.
• Sends the request to the server.

Example of an HTTP request:

POST /api/users HTTP/1.1
Host: example.com
Content-Type: application/json
Authorization: Bearer token123

{"name": "John", "age": 30}

In Node.js, IncomingMessage objects (for requests) and ServerResponse objects (for responses) are used to handle HTTP requests, allowing reading the request line, headers, and body.