Await signalr message in client

Question

Is it possible for a SignalR client send a message to the server and then to await for a seperate message (not a return value) from the server?

The theory;

Client1 send message1 to Server and "waits" for the response.
Server processes some logic
Server sends message2 to Client1 and Client1 executes the waiting code.

Call to the server:

$.connection.myhub.server.myRequest(id).done(()==>{
  // myRequest is done;
  // the server has received the request but hasn't processed it yet.
  // I want put some *async* code here to do something when the server has triggered $.connection.myhub.client.myResponse(id, someParam);
});

Callback to the client:

$.connection.myhub.client.myResponse(originalId, somePassedBackValue);

Can I use Async/Await, or wrap this in a Promise somehow?

If this isn't acheivable in SignalR are there anyother socket libraries that might be used instead?

M.Nar M.Nar · Accepted Answer · 2017-12-19T16:47:49

You can do something, like the following:

Imagine you have a client that joins a group, updates a table and then notifies the client that it has joined.

Client

msgHub.server.joinGroup(id).done(function () {
    console.log("Joined Group");
    serverCallFinished = true;
})

msgHub.client.displayTable = function (table) {
    display(table);
}

Hub

public async Task JoinGroup(string practiceId)
{
    try
    {
        await Groups.Add(Context.ConnectionId, practiceId);
        //Add new table
        var table = new Table(practiceId)
        await UpdateTable("SomeGroup", table);
    }
    catch (Exception e)
    {
        throw;
    }
}

public async Task UpdateInfo(string groupName, string table)
    {
        //await some logic
        Clients.Group(groupName).updateTable(table);
    }

Update info will call the client with message2 in this case a table that it wants to display to the client. When it finishes the it will return from its awaited state by JoinGroup which will return and alert that a new user has joined a group.

Await signalr message in client

1 Answers