Understanding Server Response in Node.js
What is a Server Response?
- When a client (like a browser) sends a request to a server (e.g., by visiting
google.com), the server processes the request and sends back a response. - This response can be HTML, JSON, plain text, files, or anything else.
Example:
When you visit google.com, the server sends back HTML that builds the Google homepage on your screen.
Basic Example of Server Response
const http = require("http");
http
.createServer((req, resp) => {
resp.setHeader("Content-Type", "text/html"); // Tell browser the response is HTML
resp.write("<h1>Hello Anil Sidhu</h1>");
resp.end(); // End the response
})
.listen("4800");
How to run:
- Save as
app.js - Run:
nodemon app.jsornode app.js - Open your browser and go to: http://localhost:4800
Passing Variables and Functions in Response
You can also include variables, functions, or dynamic values (like current time):
const http = require("http");
const age = 29;
http
.createServer((req, resp) => {
resp.setHeader("Content-Type", "text/html");
resp.write(`
<html>
<head>
<title>Code Step by Step</title>
</head>
<body>
<h1>Hello Anil Sidhu</h1>
<h2>Age: ${age}</h2>
<h2>Current Date & Time: ${Date()}</h2>
</body>
</html>
`);
resp.end();
})
.listen(4800);
resp.setHeader("Content-Type", "text/html"): Tells the browser that we’re sending back HTML.- Template literals (
` `): Used to inject JavaScript variables likeageandDate()into the HTML.