websocket выключается из-за простоя PHP

const WebSocket = require('ws'); 
 
function WebSocketClient(){ 
	this.number = 0;	// Message number 
	this.autoReconnectInterval = 5*1000;	// ms 
} 
WebSocketClient.prototype.open = function(url){ 
	this.url = url; 
	this.instance = new WebSocket(this.url); 
	this.instance.on('open',()=>{ 
		this.onopen(); 
	}); 
	this.instance.on('message',(data,flags)=>{ 
		this.number ++; 
		this.onmessage(data,flags,this.number); 
	}); 
	this.instance.on('close',(e)=>{ 
		switch (e.code){ 
		case 1000:	// CLOSE_NORMAL 
			console.log("WebSocket: closed"); 
			break; 
		default:	// Abnormal closure 
			this.reconnect(e); 
			break; 
		} 
		this.onclose(e); 
	}); 
	this.instance.on('error',(e)=>{ 
		switch (e.code){ 
		case 'ECONNREFUSED': 
			this.reconnect(e); 
			break; 
		default: 
			this.onerror(e); 
			break; 
		} 
	}); 
} 
WebSocketClient.prototype.send = function(data,option){ 
	try{ 
		this.instance.send(data,option); 
	}catch (e){ 
		this.instance.emit('error',e); 
	} 
} 
WebSocketClient.prototype.reconnect = function(e){ 
	console.log(`WebSocketClient: retry in ${this.autoReconnectInterval}ms`,e); 
        this.instance.removeAllListeners(); 
	var that = this; 
	setTimeout(function(){ 
		console.log("WebSocketClient: reconnecting..."); 
		that.open(that.url); 
	},this.autoReconnectInterval); 
} 
WebSocketClient.prototype.onopen = function(e){	console.log("WebSocketClient: open",arguments);	} 
WebSocketClient.prototype.onmessage = function(data,flags,number){	console.log("WebSocketClient: message",arguments);	} 
WebSocketClient.prototype.onerror = function(e){	console.log("WebSocketClient: error",arguments);	} 
WebSocketClient.prototype.onclose = function(e){	console.log("WebSocketClient: closed",arguments);	} 
 
var wsc = new WebSocketClient(); 
wsc.open('wss://localhost:8080/'); 
wsc.onopen = function(e){ 
	console.log("WebSocketClient connected:",e); 
	this.send("Hello World !"); 
} 
wsc.onmessage = function(data,flags,number){ 
	console.log(`WebSocketClient message #${number}: `,data); 
}