http2-wrapper
HTTP/2 client, just with the familiar
httpsAPI
This package was created to support HTTP/2 without the need to rewrite your code.
I recommend adapting to the http2 module if possible - it's much simpler to use and has many cool features!
Tip: http2-wrapper is very useful when you rely on other modules that use the HTTP/1 API and you want to support HTTP/2.
Pro Tip: While the native http2 doesn't have agents yet, you can use http2-wrapper Agents and still operate on the native HTTP/2 streams.
Installation
$ npm install http2-wrapper
$ yarn add http2-wrapper
Usage
const http2 = require('http2-wrapper');
const options = {
hostname: 'nghttp2.org',
protocol: 'https:',
path: '/httpbin/post',
method: 'POST',
headers: {
'content-length': 6
}
};
const request = http2.request(options, response => {
console.log('statusCode:', response.statusCode);
console.log('headers:', response.headers);
const body = [];
response.on('data', chunk => {
body.push(chunk);
});
response.on('end', () => {
console.log('body:', Buffer.concat(body).toString());
});
});
request.on('error', console.error);
request.write('123');
request.end('456');
// statusCode: 200
// headers: [Object: null prototype] {
// ':status': 200,
// date: 'Fri, 27 Sep 2019 19:45:46 GMT',
// 'content-type': 'application/json',
// 'access-control-allow-origin': '*',
// 'access-control-allow-credentials': 'true',
// 'content-length': '239',
// 'x-backend-header-rtt': '0.002516',
// 'strict-transport-security': 'max-age=31536000',
// server: 'nghttpx',
// via: '1.1 nghttpx',
// 'alt-svc': 'h3-23=":4433"; ma=3600',
// 'x-frame-options': 'SAMEORIGIN',
// 'x-xss-protection': '1; mode=block',
// 'x-content-type-options': 'nosniff'
// }
// body: {
// "args": {},
// "data": "123456",
// "files": {},
// "form": {},
// "headers": {
// "Content-Length": "6",
// "Host": "nghttp2.org"
// },
// "json": 123456,
// "origin": "xxx.xxx.xxx.xxx",
// "url": "https://nghttp2.org/httpbin/post"
// }API
Note: The session option was renamed to tlsSession for better readability.
Note: The timeout option applies to HTTP/2 streams only. In order to set session timeout, pass an Agent with custom timeout option set.
http2.auto(url, options, callback)
Performs ALPN negotiation.
Returns a Promise giving proper ClientRequest instance (depending on the ALPN).
Note: The agent option represents an object with http, https and http2 properties.
const http2 = require('http2-wrapper');
const options = {
hostname: 'httpbin.org',
protocol: 'http:', // Try changing this to https:
path: '/post',
method: 'POST',
headers: {
'content-length': 6
}
};
(async () => {
try {
const request = await http2.auto(options, response => {
console.log('statusCode:', response.statusCode);
console.log('headers:', response.headers);
const body = [];
response.on('data', chunk => body.push(chunk));
response.on('end', () => {
console.log('body:', Buffer.concat(body).toString());
});
});
request.on('error', console.error);
request.write('123');
request.end('456');
} catch (error) {
console.error(error);
}
})();
// statusCode: 200
// headers: { connection: 'close',
// server: 'gunicorn/19.9.0',
// date: 'Sat, 15 Dec 2018 18:19:32 GMT',
// 'content-type': 'application/json',
// 'content-length': '259',
// 'access-control-allow-origin': '*',
// 'access-control-allow-credentials': 'true',
// via: '1.1 vegur' }
// body: {
// "args": {},
// "data": "123456",
// "files": {},
// "form": {},
// "headers": {
// "Connection": "close",
// "Content-Length": "6",
// "Host": "httpbin.org"
// },
// "json": 123456,
// "origin": "xxx.xxx.xxx.xxx",
// "url": "http://httpbin.org/post"
// }http2.auto.protocolCache
An instance of quick-lru used for ALPN cache.
There is a maximum of 100 entries. You can modify the limit through protocolCache.maxSize - note that the change will be visible globally.
http2.auto.createResolveProtocol(cache, queue, connect)
cache
Type: Map<string, string>
This is the store where cached ALPN protocols are put into.
queue
Type: Map<string, Promise>
This is the store that contains pending ALPN negotiation promises.
connect
Type: (options, callback) => TLSSocket | Promise<TLSSocket>
See https://github.com/szmarczak/resolve-alpn#connect
http2.auto.resolveProtocol(options)
Returns a Promise<{alpnProtocol: string}>.
http2.request(url, options, callback)
Same as https.request.
options.h2session
Type: Http2Session
The session used to make the actual request. If none provided, it will use options.agent to get one.
http2.get(url, options, callback)
Same as https.get.
new http2.ClientRequest(url, options, callback)
Same as https.ClientRequest.
new http2.IncomingMessage(socket)
Same as https.IncomingMessage.
new http2.Agent(options)
Note: this is not compatible with the classic http.Agent.
Usage example:
const http2 = require('http2-wrapper');
class MyAgent extends http2.Agent {
createConnection(origin, options) {
console.log(`Connecting to ${http2.Agent.normalizeOrigin(origin)}`);
return http2.Agent.connect(origin, options);
}
}
http2.get({
hostname: 'google.com',
agent: new MyAgent()
}, response => {
response.on('data', chunk => console.log(`Received chunk of ${chunk.length} bytes`));
});options
Each option is an Agent property and can be changed later.
timeout
Type: number
Default: 0
If there's no activity after timeout milliseconds, the session will be closed. If 0, no timeout is applied.
maxSessions
Type: number
Default: Infinity
The maximum amount of sessions in total.
maxEmptySessions
Type: number
Default: 10
The maximum amount of empty sessions in total. An empty session is a session with no pending requests.
maxCachedTlsSessions
Type: number
Default: 100
The maximum amount of cached TLS sessions.
agent.protocol
Type: string
Default: https:
agent.settings
Type: object
Default: {enablePush: false}
Settings used by the current agent instance.
agent.normalizeOptions(options)
Returns a string representing normalized options.
Agent.normalizeOptions({servername: 'example.com'});
// => ':::::::::::::::::::::::::::::::::::::'agent.getSession(origin, options)
origin
Type: string URL object
Origin used to create new session.
options
Type: object
Options used to create new session.
Returns a Promise giving free Http2Session. If no free sessions are found, a new one is created.
A session is considered free when pending streams count is less than max concurrent streams settings.
agent.getSession(origin, options, listener)
listener
Type: object
{
reject: error => void,
resolve: session => void
}If the listener argument is present, the Promise will resolve immediately. It will use the resolve function to pass the session.
agent.request(origin, options, headers, streamOptions)
Returns a Promise giving Http2Stream.
agent.createConnection(origin, options)
Returns a new TLSSocket. It defaults to Agent.connect(origin, options).
agent.closeEmptySessions(count)
count
Type: number
Default: Number.POSITIVE_INFINITY
Makes an attempt to close empty sessions. Only sessions with 0 concurrent streams will be closed.
agent.destroy(reason)
Destroys all sessions.
agent.emptySessionCount
Type: number
A number of empty sessions.
agent.pendingSessionCount
Type: number
A number of pending sessions.
agent.sessionCount
Type: number
A number of all sessions held by the Agent.
Event: 'session'
agent.on('session', session => {
// A new session has been created by the Agent.
});Proxy support
Currently http2-wrapper provides support for these proxies:
HttpOverHttp2HttpsOverHttp2Http2OverHttp2Http2OverHttpHttp2OverHttps
Any of the above can be accessed via http2wrapper.proxies. Check out the examples/proxies directory to learn more.
Note: If you use the http2.auto function, the real IP address will leak. http2wrapper is not aware of the context. It will create a connection to the end server using your real IP address to get the ALPN protocol. Then it will create another connection using proxy. To migitate this, you need to pass a custom resolveProtocol function as an option:
const resolveAlpnProxy = new URL('https://username:password@localhost:8000');
const connect = async (options, callback) => new Promise((resolve, reject) => {
const host = `${options.host}:${options.port}`;
(async () => {
try {
const request = await http2.auto(resolveAlpnProxy, {
method: 'CONNECT',
headers: {
host
},
path: host,
// For demo purposes only!
rejectUnauthorized: false,
});
request.end();
request.once('error', reject);
request.once('connect', (response, socket, head) => {
if (head.length > 0) {
reject(new Error(`Unexpected data before CONNECT tunnel: ${head.length} bytes`));
socket.destroy();
return;
}
const tlsSocket = tls.connect({
...options,
socket
}, callback);
resolve(tlsSocket);
});
} catch (error) {
reject(error);
}
})();
});
// This is required to prevent leaking real IP address on ALPN negotiation
const resolveProtocol = http2.auto.createResolveProtocol(new Map(), new Map(), connect);
const request = await http2.auto('https://httpbin.org/anything', {
agent: {…},
resolveProtocol
}, response => {
// Read the response here
});
request.end();See unknown-over-unknown.js to learn more.
Mirroring another server
See examples/proxies/mirror.js for an example.
WebSockets over HTTP/2
See examples/ws for an example.
Push streams
See examples/push-stream for an example.
Related
got- Simplified HTTP requestshttp2-proxy- A simple http/2 & http/1.1 spec compliant proxy helper for Node.
License
MIT