The http2ServerRequest.scheme property in Node.js returns the scheme used for an incoming HTTP/2 request. It indicates the protocol through which the client accessed the server, such as http or https.
- It indicates the protocol used by the client.
- It typically returns values such as
httporhttps. - It is useful for request handling and protocol-based logic.
Syntax:
request.schemeWhere:
request: An instance of theHttp2ServerRequestobject.scheme: A read-only property that returns the scheme (httporhttps) of the incoming HTTP/2 request.
Return Value: This method returns the raw request/response trailer keys and values exactly as they were received.
Example 1:
// Node.js program to demonstrate the
// Http2ServerRequest.scheme 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) => {
// Getting scheme of http2
// by using request.scheme method
const auth = request.scheme;
console.log( "scheme pseudo header :- " + auth)
};
// Creating and initializing server
// by using http2.createServer() method
const server = http2.createServer(options, http2Handlers);
server.on('stream', (stream, requestscheme) => {
stream.respond({ ':status': 200, 'content-type':
'text/plain' });
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() scheme
server.close(() => {
console.log("server destroyed");
})
});
server.listen(8000);
// Creating and initializing client
// by using tls.connect() scheme
const client = http2.connect('http://localhost:8000');
const req = client.request({
':method': 'GET', ':path': '/'});
req.on('response', (responsescheme) => {
console.log("status : "
+ responsescheme[":status"]);
});
req.on('data', (data) => {
console.log('Received: %s ',
data.toString().replace(/(\n)/gm,""));
});
req.on('end', () => {
client.close(() => {
console.log("client destroyed");
})
});
Output:
scheme pseudo header :- http
status : 200
Received: hello
Received: priority weight : 16
client destroyed
server destroyed
Example 2:
// Node.js program to demonstrate the
// Http2ServerRequest.scheme 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) => {
// Getting scheme of http2
// by using request.scheme method
const auth = request.scheme;
response.end( "scheme pseudo header :- " + auth)
};
// 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': '/' });
req.on('data', (data) => {
console.log('Received: %s ',
data.toString().replace(/(\n)/gm,""));
});
req.on('end', () => {
client.close(() => {
console.log("client destroyed");
})
});
Output:
Received: scheme pseudo header :- http
client destroyed
server destroyed
Use Cases of http2ServerRequest.scheme
- Determining whether the request uses HTTP or HTTPS.
- Applying protocol-specific request handling.
- Redirecting users based on the request scheme.
- Logging the protocol used for incoming requests.
Reference: https://nodejs.org/dist/latest-v12.x/docs/api/http2.html#http2_request_scheme