Node.js http.ClientRequest.setHeader() Method

The http.ClientRequest.setHeader() is an inbuilt application programming interface of class ClientRequest within the HTTP module which is used to set the object of the header.

Syntax:

const request.setHeader(name, value)

Parameters: This method takes the name and value of the particular header as a parameter as key-value pair.

Return Value: This method has nothing to return.

Example 1: Filename-index.js

Javascript

// Node.js program to demonstrate the
// request.setHeader() method

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

// Create an HTTP server
http.createServer((req, res) => { })
  .listen(3000, '127.0.0.1', () => {

  // Getting client request
  const req = http.request({
    port: 3000,
    host: '127.0.0.1',
  });

  req.setHeader('content-type', 'text/html');

  console.log("before operation :- "
    + req.getHeader('content-type'))

  // Removing header by using
  // removeHeader() method
  req.removeHeader('content-type')

  console.log("after operation :- "
  + req.getHeader('content-type'))

  process.exit(0)
});

Run the index.js file using the following command:

node index.js

Output:

before operation :- text/html
after operation :- undefined

Example 2: Filename-index.js

Javascript

// Node.js program to demonstrate the
// request.setHeader() method

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

// Create an HTTP server
const server = http.createServer((req, res) => {
  res.writeHead(200, { 'Content-Type': 'text/plain' });
  res.end('okay');
});

// Now that server is running
server.listen(3000, '127.0.0.1', () => {

  // Make a request
  const options = {
    port: 3000,
    host: '127.0.0.1',
    headers: {
      'Connection': 'Upgrade',
      'Upgrade': 'websocket'
    }
  };

  // Getting client request
  const req = http.request(options);

  req.setHeader('Cookie', ['type=ninja',
            'language=javascript']);

  console.log("before operation :- "
  + req.getHeader('Cookie'))

  // Removing header by using
  // removeHeader() method
  req.removeHeader('Cookie')

  console.log("after operation :- "
  + req.getHeader('Cookie'))

  process.exit(0)
});

Run the index.js file using the following command:

node index.js

Output:

before operation :- type=ninja,language=javascript
after operation :- undefined

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