Node.js Http2ServerResponse.writeHead() Method

Last Updated : 4 Aug, 2026

The Http2ServerResponse.writeHead() method in Node.js sends the response headers and status code to the client. It is used to define the response details before the body is sent.

  • It sets the HTTP status code and headers.
  • It sends the response headers immediately.
  • It is used before sending response data.
  • It helps control how the response is started.

Syntax

response.writeHead(statusCode[, statusMessage][, headers])

Where:

  • statusCode: It is the 3-digit HTTP status code.
  • statusMessage: It is a human-readable status message. It is an optional parameter.
  • headers: This is the response header passed as a parameter. It is an optional parameter.

Return Value: The response.writeHead() method returns the Http2ServerResponse object.

Example 1:

JavaScript 
// Node.js program to demonstrate the
// Http2ServerResponse.writeHead() method
const http2 = require('http2');
const fs = require('fs');

// Private key and public certificate for access
const options = {
    key: fs.readFileSync('private-key.pem'),
    cert: fs.readFileSync('public-cert.pem'),
};

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

    // Sending the data to the client
    // by using response.writeHead() method
    response.writeHead(200, {
        'Content-Length': Buffer.byteLength('hello world'),
        'Content-Type': 'text/plain; charset=utf-8'
    });

    // Sending the signal to the client
    response.end("hello world")
};

// Creating and initializing server
// by using http2.createServer() method
const server = http2.createServer(options, http2Handlers);

server.on('stream', (stream, requestheader) => {
    stream.write('hello ');

    // Getting all information of this http2stream object
    // by using state method
    const status = stream.state;

    stream.end("priority weight : " + status.weight);

    // Stopping the server
    // by using the close() method
    server.close(() => {
        console.log("server destroyed");
    })
});

server.listen(8000);

// Creating and initializing client
// by using tls.connect() method
const client = http2.connect('http://localhost:8000');

const req = client.request({ 
    ':method': 'GET', ':path': '/' });

req.on('response', (responsesocket) => {
    console.log(responsesocket);
});

req.on('data', (data) => {
    console.log('Received: %s ',
    data.toString().replace(/(\n)/gm, ""));
});

req.on('end', () => {
    client.close(() => {
        console.log("client destroyed");
    })
});

Output:

[Object: null prototype] {
  ':status': 200,
  'content-length': '11',
  'content-type': 'text/plain; charset=utf-8',
  date: 'Sun, 06 Dec 2020 14:12:00 GMT'
}
Received: hello world
client destroyed
server destroyed

Example 2:

JavaScript 
// Node.js program to demonstrate the
// Http2ServerResponse.writeHead() method
const http2 = require('http2');
const fs = require('fs');

// Private key and public certificate for access
const options = {
    key: fs.readFileSync('private-key.pem'),
    cert: fs.readFileSync('public-cert.pem'),
};

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

    // Sending the data to the client
    // by using response.writeHead() method
    response.writeHead(200, {
        'Content-Length': Buffer.byteLength('hello world'),
        'Content-Type': 'text/plain; charset=utf-8'
    });

    // Sending the signal to client
    response.end("hello world")
};

// Creating and initializing server
// by using http2.createServer() method
const server = http2.createServer(
    options, http2Handlers);

server.on('stream', (stream, requestheader) => {

    // Stopping the server
    // by using the close() method
    server.close(() => {
        console.log("server destroyed");
    })
});

server.listen(8000);

// Creating and initializing client
// by using tls.connect() method
const client = http2.connect(
    'http://localhost:8000');

const req = client.request({ 
    ':method': 'GET', ':path': '/' });

req.on('response', (responsesocket) => {
    console.log(responsesocket);
});

req.on('end', () => {
    client.close(() => {
        console.log("client destroyed");
    })
});

Output:

[Object: null prototype] {
  ':status': 200,
  'content-length': '11',
  'content-type': 'text/plain; charset=utf-8',
  date: 'Sun, 06 Dec 2020 14:39:31 GMT'       
}

Use Cases of Http2ServerResponse.writeHead() Method

  • Setting the HTTP status code before sending a response.
  • Sending multiple response headers at once.
  • Customizing the response before writing the body.
  • Preparing consistent HTTP/2 responses.

Reference: https://nodejs.org/dist/latest-v12.x/docs/api/http2.html#http2_response_writehead_statuscode_statusmessage_headers

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