Node.js HTTP2 Complete Reference
Last Updated :
23 Feb, 2023
HTTP2 module is used to provide an implementation of the HTTP2 protocol. It reduces overheads by compressing the server request headers.
Example:
JavaScript
// Node.js program to demonstrate the
// close event 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'),
};
// Creating and initializing server
// by using http2.createServer() method
const server = http2.createServer(options);
server.on('stream', (stream, requestHeaders) => {
stream.respond({
':status': 200,
'content-type': 'text/plain'
});
stream.write('hello ');
// Getting session object
// by using session method
const http2session = stream.session;
// Getting alpnProtocol of this session
// by using alpnProtocol method
const alpnProtocol = http2session.alpnProtocol;
stream.end("session protocol : " + alpnProtocol);
http2session.close();
// Handling 'close' event
http2session.on('close',() => {
console.log("session is closed");
})
// 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', (responseHeaders) => {
console.log("status : "
+ responseHeaders[":status"]);
});
req.on('data', (data) => {
console.log('Received: %s ',
data.toString().replace(/(\n)/gm,""));
});
req.on('end', () => {
client.close(() => {
console.log("client destroyed");
})
});
Output:
status : 200
Received: hello
Received: local window size : 65535
client localSettings
server localSettings
The Complete List of HTTP2 module are listed below:
Class: Http2Session
Class: Http2Session Event
| Description
|
|---|
| timeout | There is no activity on the Http2Session after the configured number of milliseconds. |
| NClose | The ‘close’ Event in the http2 server is emitted when the Http2Session has been destroyed. |
Class: Http2Session Methods
| Description
|
|---|
| state() | Return miscellaneous information about the current state of the Http2Session. |
| socket() | It is an inbuilt application programming interface of class http2session |
| remoteSettings() | Get a prototype-less object describing the current remote settings of this Http2Session. |
| destroyed() | Check if the session is destroyed or not. |
| type() | Return the type of session instance used in the peer |
| encrypted() | Check if the Http2Session is connected with a TLSSocket or not. |
| localSettings() | Get the prototype-less object describing the current local settings of this Http2Session. |
| pendingSettingsAck() | Indicate whether the Http2Session is currently waiting for an acknowledgment of a sent SETTINGS frame. |
| close() | close this particular session. |
| closed() | Check if this Http2Session instance has been closed or not. |
| alpnProtocol() | Get the alp protocol property associated with this http2session object. |
| unref() | Return instance of the socket object associated with this session object. |
| destroy() | Destroy this particular session. |
| connecting() | Check if this Http2Session instance is still connecting or not. |
| ping() | Sends a PING frame to the connected HTTP/2 peer. |
| setTimeout() | Set the duration for a time after which a particular action will take place. |
Class: ClientHttp2Session
Class: ClientHttp2Session Methods
| Description
|
|---|
| request() | Return the object of ClientHttp2Stream. |
Class: Http2Stream
Class: Http2Stream Event
| Description
|
|---|
| Timeout | There is no activity on the Http2Stream after the configured number of milliseconds. |
| close | The ‘close’ Event in http2 server is emitted when the Http2Stream has been destroyed. |
Class: Http2Stream Methods
| Description
|
|---|
| state() | Get miscellaneous information about the current state of the Http2Stream. |
| priority() | Update the priority for this Http2Stream instance. |
| setTimeout() | Set the duration for a time after which a particular action will take place. |
| id() | Return numeric stream identifier of this Http2Stream. |
| closed() | Return true if the stream is closed other wise false. |
| endAfterHeaders() | Return true if END_STREAM flag was set in the request or response HEADERS frame received. |
| pending() | Check if Http2Stream instance has been assigned a numeric stream identifier or not. |
| destroyed() | Return true if the stream is destroyed otherwise false. |
| session() | Get a reference to the Http2Session instance that owns this Http2Stream. |
| close() | Close the Http2Stream instance. |
| rstCode() | Set to the RST_STREAM error code reported when the Http2Stream is destroyed. |
| sentHeaders() | Get the object containing the outbound headers sent to this Http2Stream. |
| sentInfoHeaders() | Get the object containing the outbound headers sent to this Http2Stream. |
Class: ServerHttp2Stream
Class: ServerHttp2Stream Method
| Description
|
|---|
| additionalHeaders() | Send an additional informational HEADERS frame to the connected HTTP/2 peer. |
| headersSent() | Check if the header were sent or not. |
| pushAllowed() | Check if the header were sent or not |
| respond() | This is used to sent the response header of the particular stream to its client. |
Class: http2.Http2ServerRequest
Class: http2.Http2ServerRequest Properties
| Description
|
|---|
| aborted | Check if the particular server request is aborted or not. |
Class: http2.Http2ServerRequest Event
| Description
|
|---|
| close | The ‘close’ Event in the http2 server is emitted when an underlying Http2Stream was closed. |
Class: http2.Http2ServerRequest Method
| Description
|
|---|
| url() | Get the Request URL string. This contains only the URL that is present in the actual HTTP request. |
| httpVersion() | Get the HTTP version either associated with server or client. |
| headers() | Get the request/response headers object. |
| rawHeaders() | Get the raw request/response headers to list exactly as they were received. |
| destroy() | This is used to destroy the request. |
| authority() | Get the string representation of the request authority pseudo-header field. |
| complete() | Check whether this request has been completed, aborted, or destroyed or not. |
| method() | Get the string representation of the request . |
| scheme() | Get the request scheme pseudo-header field indicating the scheme portion of the target URL. |
| .rawTrailers() | Get the raw request/response trailer keys and values exactly as they were received. |
| socket() | Get a Proxy object that acts as a net.Socket (or tls.TLSSocket). |
Class: http2.Http2ServerResponse
Class: http2.Http2ServerResponse Properties
| Description
|
|---|
| headersSent | Check if headers were sent or not. |
Class: http2.Http2ServerResponse Event
| Description
|
|---|
| close | The ‘close’ Event in the http2 server is emitted when an underlying Http2Stream was closed. |
| finish | The ‘finish’ event in the http2 server is emitted when the last segment of the response headers and body have been sent. |
Class: http2.Http2ServerResponse Method
| Description
|
|---|
| setHeader() | Set the header name and the particular value of that data header. |
| setTimeout() | Set the duration for a time after which a particular action will take place. |
| stream() | Get the object of HTTP stream backing this response. |
| statusMessage() | Return an empty string because it is not supported by HTTP/2 (RFC 7540 8.1.2.4). |
| writableEnded() | Check if the response.end() has been called or not. |
| write() | Send the chunk of the response body to the client. |
| writeHead() | Send the response header to the request. |
| sendDate() | Check if the Date header is automatically generated and sent in the response or not. |
| socket() | Get a Proxy object that acts as a net.Socket. |
| statusCode() | Show the different status of data header during the transaction. |
| getHeaderNames() | Return an array containing the unique names of the current outgoing headers. |
| removeHeader() | Remove a header that has been queued for implicit sending. |
| hasHeader() | Check if the header identified by name is currently set in the outgoing headers or not. |
| getHeaders() | Return a shallow copy of the current outgoing headers. |
| end() | Send the signal that all the response header and body have been sent. |
| finished() | Check whether the response has completed or not. |
| getHeader() | Read out a header that has already been queued but not sent to the client. |
http2.constants:
http2.constants Properties
| Description
|
|---|
| constants | Provide the error codes for particular errors. |
http2 Methods:
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