Node.js Http2ServerResponse.headersSent Property

Last Updated : 09 Dec, 2020

The Http2ServerResponse.headersSent is an inbuilt application programming interface of the class Http2ServerResponse within the http2 module which is used to check if headers were sent or not.

Syntax:

response.headersSent

Parameters: This property does not accept any arguments as a parameter.

Return Value: This property returns true if and only if headers were sent, otherwise false.

How to generate a Private key and Public certificate?

1. Filename: Private key

Open notepad and copy-paste the following key and save the file as private-key.pem

2. Filename: Public certificate

Open notepad and copy-paste the following key and save the file as public-cert.pem

Example 1: Filename: index.js

Javascript

// Node.js program to demonstrate the 
// Http2ServerResponse.headersSent 
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) => { 
    // Setting new header 
    response.setHeader( 
      'Content-Type',  
      'hello world; charset=utf-8'
    ); 
  
    // Checking if the header is sent or not 
    // by using headersSent method 
    const value = response.headersSent 
  
    // Display the header 
    if(value) { 
        console.log("header is sent") 
    } else { 
        console.log("header is not sent") 
    } 
}; 
  
// 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("status : " + responsesocket[":status"]); 
}); 
  
req.on('data', (data) => { 
  console.log('Received: %s ', 
  data.toString().replace(/(\n)/gm,"")); 
}); 
  
req.on('end', () => { 
  client.close(() => { 
    console.log("client destroyed"); 
  }) 
});

Run the index.js file using the following command:

node index.js

Output:

header is not sent
status : 200
Received: hello
Received: priority weight : 16
client destroyed
server destroyed

Example 2: Filename: index.js

Javascript

// Node.js program to demonstrate the 
// Http2ServerResponse.headersSent 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) => { 
    // Setting new header 
    response.setHeader('Foo', 'bar'); 
    response.setHeader( 
      'Set-Cookie', ['foo=bar', 'bar=baz']); 
  
    // Sending the header 
    response.end("hello"); 
  
    // Checking if the header is sent or not 
    // by using headersSent method 
    const value = response.headersSent 
  
    // Display the header 
    if(value) console.log("header is sent") 
    else console.log("header is not sent") 
}; 
  
// Creating and initializing server 
// by using http2.createServer() method 
const server = http2.createServer(options, http2Handlers); 
  
server.on('stream', (stream, requestHeaders) => { 
  
    // Getting all information of this http2stream 
    // object by using state method 
    const status = stream.state; 
  
    stream.end("The sum weight of all Http2Stream : "
        + status.sumDependencyWeight); 
  
    // 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': '/www.geeksforgeeks.org' }); 
  
req.on('data', (data) => { 
  console.log('Received: %s ', 
  data.toString().replace(/(\n)/gm,"")); 
}); 
  
req.on('end', () => { 
  client.close(() => { 
    console.log("client destroyed"); 
  }) 
});

Run the index.js file using the following command:

node index.js

Output:

header is sent
Received: hello
client destroyed
server destroyed

Reference: https://nodejs.org/dist/latest-v12.x/docs/api/http2.html#http2_response_headerssent

Node.js Http2ServerResponse close Event

RohitPrasad3

Improve

Article Tags :

Node.js Http2ServerResponse.headersSent Property

Javascript

Javascript

Similar Reads

Http2Session Event

Http2Session Methods

ClientHttp2Session Methods

Http2Stream Event

Http2Stream Methods

ServerHttp2Stream Method

http2.Http2ServerRequest Properties

http2.Http2ServerRequest Event

http2.Http2ServerRequest Method

http2.Http2ServerResponse Properties

Thank You!

What kind of Experience do you want to share?