NodeJS服务器没有从Swift客户端接收Socket.emit（）

Question

I am trying to put together a very simply multiplayer tic-tac-toe game in swift with a NodeJS backend. When I try and do socket.emit() from my swift client, however, the server does not recognize it.

Client Code:

SocketIOManager:

import UIKit

class SocketIOManager: NSObject {
    static let sharedInstance = SocketIOManager()

    override init() {
        super.init()
    }

    var socket: SocketIOClient = SocketIOClient(socketURL: NSURL(string: "http://10.0.1.30:2000")! as URL)

    func connectToServer(completionHandler: @escaping (_ userList: [[String: AnyObject]]?) -> Void) {
        socket.emit("connectUser")

        socket.on("userList") { ( dataArray, ack) -> Void in
            completionHandler(_: dataArray[0] as? [[String: AnyObject]])
        }
    }

    func establishConnection() {
        socket.connect()
    }

    func closeConnection() {
        socket.disconnect()
    }
}

Game Scene:

import SpriteKit

class GameScene: SKScene {

    let screenSize = UIScreen.main.bounds
    var board = SKSpriteNode(imageNamed: "Board.png")

    var users = [[String: AnyObject]]()

    override func didMove(to view: SKView) {
        SocketIOManager.sharedInstance.connectToServer(completionHandler: { (userList) -> Void in
            DispatchQueue.main.async(execute: { () -> Void in
                if userList != nil {
                    self.users = userList!
                }
            })
        })

        board.size = CGSize(width: screenSize.width * 2/3, height: screenSize.width * 2/3)
        board.position = CGPoint(x: screenSize.width/2, y: screenSize.height/2)

        self.backgroundColor = UIColor.white
        self.addChild(board)
    }

    override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {

    }

    override func update(_ currentTime: TimeInterval) {

    }
}

Server Code:

var app = require('express')();
var http = require('http').Server(app);
var io = require('socket.io')(http);

var userList = [];

app.get('/', function(req, res){
    res.send('<h1>Tic-Tac-Toe Server</h1>');
});

http.listen(2000, function(){
    console.log('Listening on *:2000');
});

io.on('connection', function(clientSocket) {
    console.log('a user connected');

    clientSocket.on('disconnect', function() {
        console.log('user disconnected');
    });

    clientSocket.on('connectUser', function() {
        console.log('User with id ' + clientSocket.id + ' connected');

        var userInfo = {};
        var foundUser = false;

        for (var i = 0; i < userList.length; i++) {
            if (userList[i]["id"] == clientSocket.id) {
                userInfo = userList[i];
                foundUser = true;
                break;
            }
        }

        if (!foundUser) {
            userInfo["id"] = clientSocket.id;
            userList.push(userInfo);
        }

        io.emit("userList", userList);
        io.emit("userConnectUpdate", userInfo);
    });

});

The message in particular that is not working is the "connectUser" one, but I have tried to create others to test it and none of them work. It appears as if the server never receives them.

Answer 1

Since you are not using a https ( http://10.0.1.30:2000 ), probably you forgot to set Allow Arbitrary Loads to YES in your Info.plist file at your iOS project:

Anyways I've built a basic example that's working:

Server side:

var app = require('express')();
var http = require('http').Server(app);
var io = require('socket.io')(http);

var port = 5000;

io.on('connection', function(socket) {
  socket.on('message', function(data) {
    console.log('client sent a message: ' + data);
  });
});

http.listen(port, function() {
  console.log('server up and running at %s port', port);
});

---

Client side:

import UIKit
import SocketIO

class ViewController: UIViewController {

  let socket = SocketIOClient(socketURL: URL(string: "http://localhost:5000")!)

  override func viewDidLoad() {
    super.viewDidLoad()

    socket.on("connect") { data, ack in
      print("socket connected")

      self.socket.emit("message", "Hello dear server from iOS.")
    }

    socket.connect()
  }

}

Logs from Server