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socket.io: Manually track client connections/disconnections 

This change is required for socket.io 3.x because in 3.x
`io.sockets.clients()` no longer returns all client Socket objects.
pull/4770/head
Richard Hansen 2021-02-13 01:15:14 -05:00 committed by John McLear
parent 66544be354
commit 01c83917d1
1 changed files with 41 additions and 14 deletions
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55
src/node/hooks/express/socketio.js
View File

@ -1,31 +1,49 @@
'use strict';
const events = require('events');
const express = require('../express');
const log4js = require('log4js');
const proxyaddr = require('proxy-addr');
const settings = require('../../utils/Settings');
const socketio = require('socket.io');
const socketIORouter = require('../../handler/SocketIORouter');
const hooks = require('../../../static/js/pluginfw/hooks');
const padMessageHandler = require('../../handler/PadMessageHandler');
const util = require('util');
let io;
const logger = log4js.getLogger('socket.io');
const sockets = new Set();
const socketsEvents = new events.EventEmitter();
exports.expressCloseServer = async () => {
// According to the socket.io documentation every client is always in the default namespace (and
// may also be in other namespaces).
const ns = io.sockets; // The Namespace object for the default namespace.
// Disconnect all socket.io clients. This probably isn't necessary; closing the socket.io Engine
// (see below) probably gracefully disconnects all clients. But that is not documented, and this
// doesn't seem to hurt, so hedge against surprising and undocumented socket.io behavior.
for (const id of await util.promisify(ns.clients.bind(ns))()) {
ns.connected[id].disconnect(true);
}
// Don't call io.close() because that closes the underlying HTTP server, which is already done
// elsewhere. (Closing an HTTP server twice throws an exception.) The `engine` property of
// socket.io Server objects is undocumented, but I don't see any other way to shut down socket.io
// without also closing the HTTP server.
if (io == null) return;
logger.info('Closing socket.io engine...');
// Close the socket.io engine to disconnect existing clients and reject new clients. Don't call
// io.close() because that closes the underlying HTTP server, which is already done elsewhere.
// (Closing an HTTP server twice throws an exception.) The `engine` property of socket.io Server
// objects is undocumented, but I don't see any other way to shut down socket.io without also
// closing the HTTP server.
io.engine.close();
// Closing the socket.io engine should disconnect all clients but it is not documented. Wait for
// all of the connections to close to make sure, and log the progress so that we can troubleshoot
// if socket.io's behavior ever changes.
//
// Note: `io.sockets.clients()` should not be used here to track the remaining clients.
// `io.sockets.clients()` works with socket.io 2.x, but not with 3.x: With socket.io 2.x all
// clients are always added to the default namespace (`io.sockets`) even if they specified a
// different namespace upon connection, but with socket.io 3.x clients are NOT added to the
// default namespace if they have specified a different namespace. With socket.io 3.x there does
// not appear to be a way to get all clients across all namespaces without tracking them
// ourselves, so that is what we do.
let lastLogged = 0;
while (sockets.size > 0) {
if (Date.now() - lastLogged > 1000) { // Rate limit to avoid filling logs.
logger.info(`Waiting for ${sockets.size} socket.io clients to disconnect...`);
lastLogged = Date.now();
}
await events.once(socketsEvents, 'updated');
}
logger.info('All socket.io clients have disconnected');
};
exports.expressCreateServer = (hookName, args, cb) => {
@ -59,6 +77,15 @@ exports.expressCreateServer = (hookName, args, cb) => {
maxHttpBufferSize: 1 << 20, // 1MiB
});
io.on('connect', (socket) => {
sockets.add(socket);
socketsEvents.emit('updated');
socket.on('disconnect', () => {
sockets.delete(socket);
socketsEvents.emit('updated');
});
});
io.use((socket, next) => {
const req = socket.request;
// Express sets req.ip but socket.io does not. Replicate Express's behavior here.