openrowingmonitor/app/WebServer.js

78 lines
2.0 KiB
JavaScript

'use strict'
/*
Open Rowing Monitor, https://github.com/laberning/openrowingmonitor
Creates the WebServer which serves the static assets and communicates with the clients
via WebSockets
*/
import { WebSocket, WebSocketServer } from 'ws'
import finalhandler from 'finalhandler'
import http from 'http'
import serveStatic from 'serve-static'
import log from 'loglevel'
import EventEmitter from 'events'
function createWebServer () {
const emitter = new EventEmitter()
const port = process.env.PORT || 80
const serve = serveStatic('./build', { index: ['index.html'] })
const server = http.createServer((req, res) => {
serve(req, res, finalhandler(req, res))
})
server.listen(port, (err) => {
if (err) throw err
log.info(`webserver running on port ${port}`)
})
const wss = new WebSocketServer({ server })
wss.on('connection', function connection (client) {
log.debug('websocket client connected')
emitter.emit('clientConnected', client)
client.on('message', function incoming (data) {
try {
const message = JSON.parse(data)
if (message) {
emitter.emit('messageReceived', message, client)
} else {
log.warn(`invalid message received: ${data}`)
}
} catch (err) {
log.error(err)
}
})
client.on('close', function () {
log.debug('websocket client disconnected')
})
})
function notifyClient (client, type, data) {
const messageString = JSON.stringify({ type, data })
if (wss.clients.has(client)) {
if (client.readyState === WebSocket.OPEN) {
client.send(messageString)
}
} else {
log.error('trying to send message to a client that does not exist')
}
}
function notifyClients (type, data) {
const messageString = JSON.stringify({ type, data })
wss.clients.forEach(function each (client) {
if (client.readyState === WebSocket.OPEN) {
client.send(messageString)
}
})
}
return Object.assign(emitter, {
notifyClient,
notifyClients
})
}
export { createWebServer }