Node.js http.IncomingMessage.rawHeaders Method

The http.IncomingMessage.rawHeaders is an inbuilt application programming interface of class Incoming Message within http module which is used to get the raw request/response headers to list exactly as they were received.

Syntax:

 request.rawHeaders

Parameters: This method does not accept any argument as a parameter.

Return Value: This method returns the raw request/response headers list exactly as they were received.

Request List:

Example 1: Filename: index.js

Javascript

// Node.js program to demonstrate the
// IncomingMessage.rawHeaders APi

// Importing http module
const http = require('http');

// Setting up PORT
const PORT = process.env.PORT || 3000;

// Creating http Server
const httpServer = http.createServer(
    function (request, response) {

        // Getting rawHeaders
        // by using request.rawHeaders Api
        const value = request.rawHeaders;

        // Display result
        response.end("rawHeaders : " + value[0], 'utf8', () => {
            console.log("displaying the result...");

            //Closing the server
            httpServer.close(() => {
                console.log("server is closed")
            })
        });
    });

// Listening to http Server on local port
httpServer.listen(PORT, () => {
    console.log("Server is running at port 3000...");
});

Steps to run:

node index.js

Console Output:

Server is running at port 3000...
displaying the result...
displaying the result...
server is closed
server is closed

Browser Output: Paste the localhost address http://localhost:3000/ in the search bar of the browser.

rawHeaders : Host

Example 2: Filename: index.js

Javascript

// Node.js program to demonstrate the
// IncomingMessage.rawHeaders APi

// Importing http module
const http = require('http');

// Request and response handler
const http2Handlers = (request, response) => {

    // Getting rawHeaders
    // by using request.rawHeaders Api
    const value = request.rawHeaders;

    // Display result
    response.end("rawHeaders : " + value[2], 'utf8', () => {
        console.log("displaying the result...");

        //Closing the Server
        httpServer.close(() => {
            console.log("server is closed")
        })
    });
};

// Creating http Server and execute the server
const httpServer = http.createServer(
    http2Handlers).listen(3000, () => {
        console.log("Server is running at port 3000...");
    });

Steps to run:

node index.js

Console Output:

Server is running at port 3000...
displaying the result...
displaying the result...
server is closed
server is closed

Browser Output: Paste the localhost address http://localhost:3000/ in the search bar of the browser.

rawHeaders : Connection

Reference: https://nodejs.org/dist/latest-v12.x/docs/api/http.html#http_message_rawheaders