I have to make a chat for a Xamarin Forms (PCL) application. I'm using the NuGet package SocketIoClientDotNet for socket.
At first I could not connect at all. After many researches on internet I found this open issue on Github, so I downgraded the library but also all the dependencies:
EngineIOClient.Net V0.9.22
SocketIOClientDotNet V0.9.13
WebSocket4Net V0.14.1.0
It was better, the connection seemed to work but I encountered a new issue: the connection is very instable and it's difficult for me to test anything cause of that. One time it can connect multiple times, one time it not connect at all, it's very annoying...
My code is very simple:
Common Code:
ISocketIO interface:
public interface ISocketIO
{
void Connect(string url);
void On(string eventString, Action<object> action);
}
MsgService class:
readonly string EVENT_CONNECT = "connect";
public MsgService(ISocketIO socket)
{
Socket = socket;
if (Socket != null)
{
Socket.On(EVENT_CONNECT, () =>
{
(code here...)
});
}
}
public void Connect()
{
if (Socket != null)
{
Socket.Connect("chat_url_here");
}
}
App class:
public partial class App : Application
{
public static MsgService MsgService;
public App(ISocketIO socket)
{
InitializeComponent();
Language = Language.FRENCH;
MsgService = new MsgService(socket);
MsgService.Connect();
MainPage = new NavigationPage(new MainPage());
}
...
}
iOS code (same for Android):
Class SocketIO
[assembly: Xamarin.Forms.Dependency(typeof(SocketIO))]
namespace MeetYou.iOS
{
public class SocketIO : ISocketIO
{
Socket _socket;
public void Connect(string url)
{
IO.Options opt = new IO.Options
{
Path = "path_here"
};
_socket = IO.Socket(url, opt);
_socket.Connect();
}
}
}
AppDelegate:
[Register("AppDelegate")]
public class AppDelegate : Xamarin.Forms.Platform.iOS.FormsApplicationDelegate
{
public override bool FinishedLaunching(UIApplication uiApplication, NSDictionary launchOptions)
{
Xamarin.Forms.Forms.Init();
LoadApplication(new App(new SocketIO()));
return base.FinishedLaunching(uiApplication, launchOptions);
}
}
Maybe I'm doing something wrong of maybe it exists an other plugin I could use instead this one.
Have you tried running this without this line?
_socket.Connect();
I managed to make my example work in my application only using the
_socket = IO.Socket("wss://" + HostUrl + "/");
Related
I ran into a problem in the last step of a test project using Photon Network. When you first connect and join the room, everything goes without errors. However, after completing the match, exiting the room, and using LoadScene(), errors appear:
JoinLobby operation (229) not called because client is not connected or not yet ready, client state: JoiningLob <- in OnConnectedToMaster()
Through experience, I realized that the ConnectUsingSettings() methods and other Photon methods are called multiple times. But the connection to the lobby happens and I can create a room, but I immediately encounter MissingReferenceException errors.
I've seen a solution from guys who ran into this very same problem. The problems arose because of the events. Wherever this could happen, I unsubscribed from the events, but that doesn't help. What else can cause such problems, because I obviously missed something that prevents me from completely closing the scene during the transition?
Sorry for my language, used Google Translate
Code:
LobbyManager.cs
private void StartConnect()
{
PhotonNetwork.NickName = master.GameSettings.NickName;
PhotonNetwork.GameVersion = master.GameSettings.NickName;
PhotonNetwork.ConnectUsingSettings();
PhotonNetwork.AutomaticallySyncScene = true;
}
public override void OnConnectedToMaster()
{
Debug.Log("Connected to server");
if(!PhotonNetwork.InLobby) PhotonNetwork.JoinLobby();
}
public override void OnJoinedLobby()
{
onConnected.Invoke();//This use for show UIElements on Canvas
}
JoinRandomRoom class
public void OnClick_JoinRandomRoom()
{
if (!PhotonNetwork.IsConnected) return;
if (GameModeGlobalData.SelectedGameMode != null)
{
SetRoomOptions();
PhotonNetwork.JoinRandomRoom(expectedRoomProperties, GameModeGlobalData.SelectedGameMode.MaxPlayers);
}
}
public override void OnJoinRandomFailed(short returnCode, string message)
{
Debug.Log("Join random failed: " + message + ". Room will be created...");
_createRoomMenu.CreateAndJoinRoom();
}
public void SetRoomOptions()
{
expectedRoomProperties[RoomData.GAME_MODE] = GameModeGlobalData.SelectedGameMode.GameModeName;
}
private void OnDisable()
{
ShowPanels.RemoveAllListeners();
}
And CreateRoom.cs
private ExitGames.Client.Photon.Hashtable _roomCustomProperties = new ExitGames.Client.Photon.Hashtable();
public void CreateAndJoinRoom()
{
if (!PhotonNetwork.IsConnected) return;
if (GameModeGlobalData.SelectedGameMode != null)
{
RoomOptions roomOptions = GetCustomRoomOptions();
roomOptions.CleanupCacheOnLeave = true;
PhotonNetwork.CreateRoom(randomRoomName, roomOptions);
}
}
public RoomOptions GetCustomRoomOptions()
{
RoomOptions options = new RoomOptions();
options.MaxPlayers = _maxPlayer;
options.IsOpen = true;
options.IsVisible = true;
string[] roomProperties = new string[]{ RoomData.GAME_MODE };
_roomCustomProperties[RoomData.GAME_MODE] = GameModeGlobalData.SelectedGameMode.GameModeName;
options.CustomRoomPropertiesForLobby = roomProperties;
options.CustomRoomProperties = _roomCustomProperties;
return options;
}
The project has grown, and I blame myself for not testing it at the very beginning. Didn't think there would be problems at this stage
Sorry for this post. Its resolved. For those who may encounter this in the future, in addition to unsubscribing from events, check all classes that inherit from MonoBehaviourPunCallbacks for overridden OnDisable() methods.
Like this:
public override void OnDisable()
{
base.OnDisable();
}
This in turn will call the
PhotonNetwork.RemoveCallbackTarget(this);
Also, from the documentation:
Do not add new MonoBehaviour.OnEnable or MonoBehaviour.OnDisable. Instead, you should override those and call base.OnEnable and base.OnDisable.
I forgot about it and used MonoBehaviour.OnDisable.
I created a .net core web api project. It has gotten kinda big and I want to program a "delete" operation which deletes a lot of stuff from the database. Since there are a lot of things to delete, this will be a long running process. So I thought maybe I can run this in the background and just write status updates somewhere for the user to see whats happening.
I googled this and I found BackgroundWorkerQueue and thought this might be my solution.
So I registered the service and everything and here is my method that calls it:
public class DeleteController : ControllerBase {
private readonly BackgroundWorkerQueue _backgroundWorkerQueue;
public AdminController(BackgroundWorkerQueue backgroundWorkerQueue){
_backgroundWorkerQueue = backgroundWorkerQueue;
}
public async Task<ActionResult> HugeDeleteMethod(int id)
{
// some prechecks here...
// and here I thought I'd start the background task
_backgroundWorkerQueue.QueueBackgroundWorkItem(async token =>
{
var a = _context.StatusTable.Find(id);
a.Status += "Blablablabla\n";
_context.StatusTable.Update(a);
await _context.SaveChangesAsync();
//now start doing delete operations
});
}
}
And that class looks like this:
public class BackgroundWorkerQueue
{
private ConcurrentQueue<Func<CancellationToken, Task>> _workItems = new ConcurrentQueue<Func<CancellationToken, Task>>();
private SemaphoreSlim _signal = new SemaphoreSlim(0);
public async Task<Func<CancellationToken, Task>> DequeueAsync(CancellationToken cancellationToken)
{
await _signal.WaitAsync(cancellationToken);
_workItems.TryDequeue(out var workItem);
return workItem;
}
public void QueueBackgroundWorkItem(Func<CancellationToken, Task> workItem)
{
if (workItem == null)
{
throw new ArgumentNullException(nameof(workItem));
}
_workItems.Enqueue(workItem);
_signal.Release();
}
}
There is also a DeleteService, which is also called in my startup, but I am not sure what it does:
public class DeleteService : BackgroundService
{
private readonly BackgroundWorkerQueue queue;
public NukeService(BackgroundWorkerQueue queue)
{
this.queue = queue;
}
protected override async Task ExecuteAsync(CancellationToken stoppingToken)
{
while (!stoppingToken.IsCancellationRequested)
{
var workItem = await queue.DequeueAsync(stoppingToken);
await workItem(stoppingToken);
}
}
}
Both are added in my startup.cs:
services.AddHostedService<DeleteService>();
services.AddSingleton<BackgroundWorkerQueue>();
Well, maybe I'm going about this all wrong. This is never called it seems, the StatusTable field "Status" is always empty. So how do I do this?
You just need to subclass BackgroundService class or implement IHostedService and than register your service as hosted service.
This will run a service in the background. Than in your service you can leverage the BlockingQueue that will perform tasks only when they are added, e.g. like this:
public class MyService : BackgroundService {
private readonly BlockingCollection<long> queue;
public MyService(){
this.queue = new BlockingCollection<long>();
Task.Run(async () => await this.Execute());
}
public void AddId(long id) {
this.queue.Add(id);
}
private async Task Execute()
{
foreach (var id in this.queue.GetConsumingEnumerable())
{
... do your stuff ...
}
}
}
services.AddHostedService<MyService>();
Here is the docu: Background services in .net core
I am developing an android app with node.js running on the backend. In the android app, I have multiple activities. I am opening a socket connection using Socket.io from the first activity. But the problem is that I don't know how to use that connection over multiple activities. I don't know how to implement this using Service. It would be great if you could answer with some code reference.
Thanks in Advance
socket.io has a chat app example implemented in android link below:
https://github.com/nkzawa/socket.io-android-chat
any way, for using socket.io in android, i think best way is using it inside a service something like this:
public class ChatService extends Service {
public void connectSocket() {
try {
IO.Options options = new IO.Options();
socket = IO.socket("http://192.168.1.1:8080", options);
socket.on(Socket.EVENT_CONNECT, new Emitter.Listener() {
#Override
public void call(Object... args) {
}
}).on(Socket.EVENT_DISCONNECT, new Emitter.Listener() {
#Override
public void call(Object... args) {
}
}).on("error", new Emitter.Listener() {
#Override
public void call(Object... args) {
}
});
socket.connect();
} catch (Exception ignored) {
}
}
#Override
public void onDestroy() {
socket.disconnect();
super.onDestroy();
}
}
I can call InvokeAsync from server code using the IHubContext interface, but sometimes I want to force these clients to disconnect.
So, is there any way to disconnect clients from server code that references the IHubContext interface?
Step 1:
using Microsoft.AspNetCore.Connections.Features;
using System.Collections.Generic;
using Microsoft.AspNetCore.SignalR;
public class ErrorService
{
readonly HashSet<string> PendingConnections = new HashSet<string>();
readonly object PendingConnectionsLock = new object();
public void KickClient(string ConnectionId)
{
//TODO: log
if (!PendingConnections.Contains(ConnectionId))
{
lock (PendingConnectionsLock)
{
PendingConnections.Add(ConnectionId);
}
}
}
public void InitConnectionMonitoring(HubCallerContext Context)
{
var feature = Context.Features.Get<IConnectionHeartbeatFeature>();
feature.OnHeartbeat(state =>
{
if (PendingConnections.Contains(Context.ConnectionId))
{
Context.Abort();
lock (PendingConnectionsLock)
{
PendingConnections.Remove(Context.ConnectionId);
}
}
}, Context.ConnectionId);
}
}
Step 2:
public void ConfigureServices(IServiceCollection services)
{
...
services.AddSingleton<ErrorService>();
...
}
Step 3:
[Authorize(Policy = "Client")]
public class ClientHub : Hub
{
ErrorService errorService;
public ClientHub(ErrorService errorService)
{
this.errorService = errorService;
}
public async override Task OnConnectedAsync()
{
errorService.InitConnectionMonitoring(Context);
await base.OnConnectedAsync();
}
....
Disconnecting without Abort() method:
public class TestService
{
public TestService(..., ErrorService errorService)
{
string ConnectionId = ...;
errorService.KickClient(ConnectionId);
In alpha 2 there is the Abort() on HubConnectionContext you could use to terminate a connection. I don't see, however, an easy way to access it from outside the hub.
Because you control the clients you could just invoke a client method and tell the client to disconnect. The advantage is that the client disconnect gracefully. The disadvantage is that it requires sending the message to the client instead of disconnecting the client solely on the server side.
How do I actually run this client/server project on ActionScript 3? I'm using flashbuilder. I'm not sure if I'm even doing the right thing, i made a new as mobile project and put in the code for my client which is this:
public class client extends Sprite
{
private var socket:Socket;
private var IP:String = "127.0.0.1";
public function client()
{
super();
socket = new Socket();
socket.addEventListener(Event.CONNECT, onConnected);
socket.connect(IP, 5555);
}
protected function onConnected(event:Event):void
{
socket.writeUTFBytes("communication between Sockets (Client socket and server socket)");
socket.flush();
}
}
and then I made a new class within the package that has the client class (as above) in it and put in this as the server class:
public class NewSocketServerTest extends Sprite
{
private var serverSocket:ServerSocket = new ServerSocket();
private var clientSocket:Socket;
private var txt:TextField;
public function NewSocketServerTest()
{
createUI();
serverSocket.bind(5555);
serverSocket.addEventListener(ServerSocketConnectEvent.CONNECT, onConnected);
serverSocket.listen();
}
protected function onConnected(event:ServerSocketConnectEvent):void
{
txt.appendText("This is a demonstration of \n" );
clientSocket = event.socket;
clientSocket.addEventListener(ProgressEvent.SOCKET_DATA, onDataHandler);
}
protected function onDataHandler(event:ProgressEvent):void
{
var str:String = clientSocket.readUTFBytes(clientSocket.bytesAvailable);
txt.appendText(str);
}
private function createUI():void
{
txt = new TextField();
txt.width=400;
txt.height=400;
txt.appendText("Hello! \n");
addChild(txt);
}
}
When I try run this in an emulator it's just a white screen and I'm not sure what I'm doing wrong.
Try specifying the serverSocket hostname.
serverSocket.bind(5555,"127.0.0.1");