Node.js Http2ServerResponse.getHeader() Method
Last Updated :
23 Nov, 2020
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The Http2ServerResponse.getHeader() is an inbuilt application programming interface of the class Http2ServerResponse within the http2 module which is used to read out a header that has already been queued but not sent to the client.
Syntax:
response.getHeader(name)
Parameters: This method takes the header name as a parameter.
Return Value: This method returns the string representation of the header.
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
-----BEGIN RSA PRIVATE KEY----- MIICXQIBAAKBgQC38R9wXcUbhOd44FavgmE5R3K4JeYOHLnI7dUq1B8/Gv7l3SOg JKef/m9gM1KvUx951mapXGtcWgwB08J3vUE2YOZ4tWJArrVZES0BI/RmFAyhQFP5 HcWl3LSM9LRihP98F33oIkKaCxA5LxOrkgpV4HrUzIKTABDYah7RPex1WQIDAQAB AoGBAIXR71xxa9gUfc5L7+TqBs+EMmrUb6Vusp8CoGXzQvRHMJCMrMFySV0131Nu o0YYRDsAh1nJefYLMNcXd1BjqI+qY8IeRsxaY+9CB2KKGVVDO2uLdurdC2ZdlWXT Vwr3dDoyR0trnXJMmH2ijTeO6bush8HuXxvxJBjvEllM5QYxAkEA3jwny9JP+RFu 0rkqPBe/wi5pXpPl7PUtdNAGrh6S5958wUoR4f9bvwmTBv1nQzExKWu4EIp+7vjJ fBeRZhnBvQJBANPjjge8418PS9zAFyKlITq6cxmM4gOWeveQZwXVNvav0NH+OKdQ sZnnDiG26JWmnD/B8Audu97LcxjxcWI8Jc0CQEYA5PhLU229lA9EzI0JXhoozIBC TlcKFDuLm88VSmlHqDyqvF9YNOpEdc/p2rFLuZS2ndB4D+vu6mjwc5iZ3HECQCxy GBHRclQ3Ti9w76lpv+2kvI4IekRMZWDWnnWfwta+DGxwCgw2pfpleBZkWqdBepb5 JFQbcxQJ0wvRYXo8qaUCQQCgTvWswBj6OTP7LTvBlU1teAN2Lnrk/N5AYHZIXW6m nUG9lYvH7DztWDTioXMrruPF7bdXfZOVJD8t0I4OUzvC -----END RSA PRIVATE KEY-----
2. Filename: Public certificate
Open notepad and copy-paste the following key and save the file as public-cert.pem
-----BEGIN CERTIFICATE----- MIICfzCCAegCCQDxxeXw914Y2DANBgkqhkiG9w0BAQsFADCBgzELMAkGA1UEBhMC SU4xEzARBgNVBAgMCldlc3RiZW5nYWwxEDAOBgNVBAcMB0tvbGthdGExFDASBgNV BAoMC1BhbmNvLCBJbmMuMRUwEwYDVQQDDAxSb2hpdCBQcmFzYWQxIDAeBgkqhkiG 9w0BCQEWEXJvZm9mb2ZAZ21haWwuY29tMB4XDTIwMDkwOTA1NTExN1oXDTIwMTAw OTA1NTExN1owgYMxCzAJBgNVBAYTAklOMRMwEQYDVQQIDApXZXN0YmVuZ2FsMRAw DgYDVQQHDAdLb2xrYXRhMRQwEgYDVQQKDAtQYW5jbywgSW5jLjEVMBMGA1UEAwwM Um9oaXQgUHJhc2FkMSAwHgYJKoZIhvcNAQkBFhFyb2ZvZm9mQGdtYWlsLmNvbTCB nzANBgkqhkiG9w0BAQEFAAOBjQAwgYkCgYEAt/EfcF3FG4TneOBWr4JhOUdyuCXm Dhy5yO3VKtQfPxr+5d0joCSnn/5vYDNSr1MfedZmqVxrXFoMAdPCd71BNmDmeLVi QK61WREtASP0ZhQMoUBT+R3Fpdy0jPS0YoT/fBd96CJCmgsQOS8Tq5IKVeB61MyC kwAQ2Goe0T3sdVkCAwEAATANBgkqhkiG9w0BAQsFAAOBgQATe6ixdAjoV7BSHgRX bXM2+IZLq8kq3s7ck0EZrRVhsivutcaZwDXRCCinB+OlPedbzXwNZGvVX0nwPYHG BfiXwdiuZeVJ88ni6Fm6RhoPtu2QF1UExfBvSXuMBgR+evp+e3QadNpGx6Ppl1aC hWF6W2H9+MAlU7yvtmCQQuZmfQ== -----END CERTIFICATE-----
Example 1: Filename: index.js
// Node.js program to demonstrate the
// Http2ServerResponse.getHeader() 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('Content-Type',
'hello world; charset=utf-8');
// Getting header
// by using getHeader() method
const value = response.getHeader('content-type')
// Display the header
console.log("header :- " + value);
};
// 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 :- hello world; charset=utf-8 status : 200 Received: hello Received: priority weight : 16 client destroyed server destroyed
Example 2: Filename: index.js
// Node.js program to demonstrate the
// Http2ServerResponse.getHeader() 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('Set-Cookie', ['type=ninja',
'language=javascript']);
// Getting header
// by using getHeader() method
const value = response.getHeader('Set-Cookie')
// Display the header
console.log("header :- " + value);
};
// 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 :- type=ninja,language=javascript Received: The sum weight of all Http2Stream : 0 client destroyed server destroyed
Reference: https://nodejs.org/dist/latest-v12.x/docs/api/http2.html#http2_response_getheader_name
