public async override Task <WebsocketSessionPeer> JoinSession(HttpContext context, string sessionType, string sessionKey)
{
WebsocketSession targetSession = GetSessionByKey(sessionKey);
if (targetSession == null)
{
targetSession = this.CreateSession(sessionType, sessionKey);
}
if (targetSession.GetPeers().Count > 0)
{
throw new Exception("Unable to join Progress session that already has a subscriber.");
}
WebSocket socket = await context.WebSockets.AcceptWebSocketAsync();
WebsocketSessionPeer peer = targetSession.AddPeer(socket);
targetSession.SetAttribute("hostId", peer.Token.PeerId);
// alert requester of their own token
WebsocketSessionPeerToken hostToken = peer.Token;
WebsocketSessionGreeting greeting = new WebsocketSessionGreeting {
SessionKey = sessionKey, HostToken = hostToken, Token = peer.Token
};
WebsocketSessionMessageResponse greetingResponse = CreateWebsocketResponseMessage(WebsocketSessionMessageType.Greeting, greeting);
SendMessage(peer, greetingResponse);
return(peer);
}
public WebsocketSessionPeer AddPeer(WebSocket socket)
{
WebsocketSessionPeer peer = new WebsocketSessionPeer(socket);
Peers.TryAdd(peer.Token.PeerId, peer);
return(peer);
}
public virtual async Task ReceiveBinary(string sessionKey, WebsocketSessionPeer sessionPeer, WebSocketReceiveResult result, byte[] buffer)
{
List <byte> byteList = new List <byte>(sessionPeer.IdAsByteArray);
byteList.AddRange(buffer);
SendBinaryToPeers(sessionKey, sessionPeer.Socket, byteList.ToArray());
}
public async override Task ReceiveMessage(string sessionKey, WebsocketSessionPeer peer, WebSocketReceiveResult result, byte[] buffer)
{
WebsocketSessionError error = new WebsocketSessionError {
ErrorCode = "WP_001", Message = "Progress Sessions do not expect messages from the client."
};
SendMessage(peer.Socket, error);
}
public virtual async Task Invoke(HttpContext context)
{
if (!context.WebSockets.IsWebSocketRequest)
{
return;
}
if (!context.Request.Path.HasValue)
{
return;
}
string path = context.Request.Path;
string[] pathArray = path.Split("/");
string sessionKey = pathArray[1];
if (string.IsNullOrEmpty(sessionKey))
{
return;
}
WebsocketSessionPeer peer = await SessionService.JoinSession(context, "stream", sessionKey);
await Receive(peer.Socket, async (result, buffer) =>
{
if (result.MessageType == WebSocketMessageType.Text)
{
await((WebsocketSessionService)SessionService).ReceiveMessage(sessionKey, peer, result, buffer);
return;
}
else if (result.MessageType == WebSocketMessageType.Binary)
{
await SessionService.ReceiveBinary(sessionKey, peer, result, buffer);
return;
}
else if (result.MessageType == WebSocketMessageType.Close)
{
WebsocketSession targetSession = SessionService.GetSessionByKey(sessionKey);
string hostId = targetSession.GetAttributeValue <string>("hostId");
// if the host quit, kill the session
if (peer.Token.PeerId == hostId)
{
await SessionService.EndSession(sessionKey);
return;
}
// otherwise, disconnect and alert host that someone has disconnected
await targetSession.RemovePeer(peer.Token.PeerId);
Models.WebsocketSessionUpdate[] updates = WebsocketSessionService.CreatePeerUpdates(Models.WebsocketSessionUpdateStatus.Disconnect, peer.Token);
Models.WebsocketSessionMessageResponse response = WebsocketSessionService.CreateWebsocketResponseMessage(Models.WebsocketSessionMessageType.StatusUpdates, updates);
SessionService.SendMessageToPeers(sessionKey, peer.Token.PeerId, response);
}
});
await _next.Invoke(context);
}
public async Task SendMessage(string sessionKey, string socketId, string message)
{
WebsocketSession session = this.GetSessionByKey(sessionKey);
if (session == null)
{
throw new Exception("Unknown Session requested: " + sessionKey);
}
WebsocketSessionPeer sessionSocket = session.GetPeerById(socketId);
if (sessionSocket == null)
{
throw new Exception("Unknown Socket requested: " + socketId);
}
await SendMessage(sessionSocket.Socket, message);
}
public override async Task Invoke(HttpContext context)
{
if (!context.WebSockets.IsWebSocketRequest)
{
return;
}
if (!context.Request.Path.HasValue)
{
return;
}
string path = context.Request.Path;
string[] pathArray = path.Split("/");
string sessionKey = pathArray[1];
if (string.IsNullOrEmpty(sessionKey))
{
return;
}
WebsocketSessionPeer peer = await SessionService.JoinSession(context, "progress", sessionKey);
await Receive(peer.Socket, async (result, buffer) =>
{
if (result.MessageType == WebSocketMessageType.Text)
{
await SessionService.ReceiveMessage(sessionKey, peer, result, buffer);
return;
}
else if (result.MessageType == WebSocketMessageType.Binary)
{
await SessionService.ReceiveBinary(sessionKey, peer, result, buffer);
return;
}
else if (result.MessageType == WebSocketMessageType.Close)
{
await SessionService.EndSession(sessionKey);
return;
}
});
await _next.Invoke(context);
}
public virtual async Task <WebsocketSessionPeer> JoinSession(HttpContext context, string sessionType, string sessionKey)
{
WebsocketSession targetSession = GetSessionByKey(sessionKey);
if (targetSession == null)
{
targetSession = this.CreateSession(sessionType, sessionKey);
}
WebSocket socket = await context.WebSockets.AcceptWebSocketAsync();
WebsocketSessionPeer sessionSocket = targetSession.AddPeer(socket);
string hostId = sessionSocket.Token.PeerId;
if (targetSession.GetPeers().Count == 1)
{
targetSession.SetAttribute("hostId", hostId);
}
else
{
hostId = targetSession.GetAttributeValue <string>("hostId");
}
// alert requester of their own token, the hosts token and other existing peers
WebsocketSessionPeerToken hostToken = targetSession.GetPeerById(hostId).Token;
WebsocketSessionPeerToken[] participants = targetSession.GetPeers().Where(pair => pair.Value.Token.PeerId != sessionSocket.Token.PeerId).Select(pair => pair.Value.Token).ToArray();
WebsocketSessionGreeting greeting = new WebsocketSessionGreeting {
SessionKey = sessionKey, HostToken = hostToken, Token = sessionSocket.Token, Peers = participants
};
WebsocketSessionMessageResponse greetingResponse = CreateWebsocketResponseMessage(WebsocketSessionMessageType.Greeting, greeting);
SendMessage(sessionSocket, greetingResponse);
return(sessionSocket);
}
// access the websocket data as a string; (if you JSON serialized, you might want to only override this function
// because you'll know that all of your data will be a string that you are going to deserialize;
// If you wanted to do something like streaming video via direct byte arrays, you'd want to override the other
// "receive" function.
public virtual async Task ReceiveMessageString(string sessionKey, WebsocketSessionPeer peer, WebSocketReceiveResult result, string socketMessage)
{
try
{
// parse the request to access the data;
WebsocketSessionMessageRequest messageRequest = System.Text.Json.JsonSerializer.Deserialize <WebsocketSessionMessageRequest>(socketMessage);
if (messageRequest.Type == WebsocketSessionMessageType.Unknown)
{
messageRequest.Type = WebsocketSessionMessageType.Text;
}
// process the request and send the response message, if applicable;
ProcessMessageRequest(messageRequest, sessionKey, peer);
}
catch (Exception exception)
{
WebsocketSessionError error = new WebsocketSessionError()
{
ErrorCode = "WP_002", Message = "An error occurred while processing the message"
};
SendMessage(peer.Socket, error);
}
}
private Task ProcessMessageRequest(WebsocketSessionMessageRequest request, string sessionKey, WebsocketSessionPeer peer)
{
// get a reference to the session
WebsocketSession session = GetSessionByKey(sessionKey);
// handle the different types of messages;
string message = "";
switch (request.Type)
{
case WebsocketSessionMessageType.Introduction:
string hostId = session.GetAttributeValue <string>("hostId");
WebsocketSessionPeerToken token = System.Text.Json.JsonSerializer.Deserialize <Models.WebsocketSessionPeerToken>(request.Message);
peer.Token.DisplayName = token.DisplayName;
peer.Token.IconUrl = token.IconUrl;
if (token.PeerId == hostId)
{
// if host, no need to request access; just grant access;
WebsocketSessionUpdate[] updates = CreatePeerUpdates(WebsocketSessionUpdateStatus.AccessGranted, peer.Token);
WebsocketSessionMessageResponse hostAlertResponse = CreateWebsocketResponseMessage(WebsocketSessionMessageType.StatusUpdates, updates);
SendMessage(sessionKey, hostId, hostAlertResponse);
return(Task.CompletedTask);
}
message = request.Message;
break;
case WebsocketSessionMessageType.StatusUpdates:
case WebsocketSessionMessageType.ByteArray:
case WebsocketSessionMessageType.Text:
message = request.Message;
break;
case WebsocketSessionMessageType.Reaction:
if (request.TargetMessageId == null)
{
throw new Exception("Reaction must provide TargetMessageId value.");
}
break;
default:
throw new Exception("Unknown Message Type: " + request.Type);
}
List <WebsocketSessionMessageResponse> messages = session.GetAttributeValue <List <WebsocketSessionMessageResponse> >("messages");
WebsocketSessionMessageResponse messageResponse = new WebsocketSessionMessageResponse()
{
MessageId = messages.Count,
MessageType = request.Type,
Message = message,
SenderId = peer.Token.PeerId,
Recipients = request.Recipients
};
messages.Add(messageResponse);
if (request.Recipients == null || request.Recipients.Length == 0)
{
SendMessageToPeers(sessionKey, peer.Token.PeerId, messageResponse);
}
else
{
SendMessage(sessionKey, request.Recipients, messageResponse);
}
return(Task.CompletedTask);
}
// access the raw bytes that were sent through the websocket;
public virtual async Task ReceiveMessage(string sessionKey, WebsocketSessionPeer sessionPeer, WebSocketReceiveResult result, byte[] buffer)
{
string message = Encoding.UTF8.GetString(buffer, 0, result.Count);
await ReceiveMessageString(sessionKey, sessionPeer, result, message);
}
public async Task SendMessage(WebsocketSessionPeer sessionSocket, string message)
{
await SendMessage(sessionSocket.Socket, message);
}
public async Task SendMessage(WebsocketSessionPeer sessionSocket, object value)
{
string message = JsonSerializer.Serialize(value);
await SendMessage(sessionSocket.Socket, message);
}
public string GetId(WebsocketSessionPeer socket)
{
return(Peers.FirstOrDefault(pair => pair.Value == socket).Key);
}
