I have 2 separate ASP.Net sites, one is outward facing serving the UI and the other is a backend API that is only ever accessed by the UI server.
We are using SignalR to push events through the client but these events originate on the backend API so there is a SignalR connection from browser -> UI Server and another from UI Server -> Backend API.
Currently each client that connects SignalR from the browser causing a new connection to be made to the backend API. This means that we have a lot of connections for the same hubs through between the same processes.
Is there any way in SignalR to have it pool the connections so they use the same underlying sockets while hiding that abstraction from my code in the SignalR .Net Client?
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I have an application that uses SignalR to broadcast data to all connected clients. Its a .NET6 Blazor Wasm hosted web application. Now, I want the the broadcaster (which is running on the Blazor server) to connect to a data source that is outside my website, and get data from there. The source data is being broadcast via UDP on a different network.
So my question is, is it possible that my SignalR hub that is running on the Blazor server connects to another SignalR hub running on a different machine in a different network and get real time data from it? Or may be I can run a SignalR client as well on my Blazor server and then connect to a machine on another network? Can I run a SignalR hub on the UDP source machine to which my Blazor server SignalR hub or client can connect? From what I have read, SignalR only runs on a website. Or is it that SignalR is not suitable for this kind of server to server data feeds?
I have some questions regarding SignalR Core on the server side;
My server is written in ASP.NET Core, and it uses SignalR for sending notifications to users. The server uses Controllers with endpoints that clients interact with.
1) Can I host the entire thing in Azure App Service and add the SignalR service to it? Or would it be better to split the SignalR code out to its own server, which is called from the "main" server when needed?
2) The SignalR Service has an option for "Serverless", which according to documentation doesn't support clients calling any server RPCs when in said mode. Could I run this thing in Serverless mode as I'm only using the sockets for sending notifications to the clients. Or is it reserved for Azure functions?
3) Is there a way to get the number of connections for a user in a SignalR hub? I would like to send a push message to the user if he doesn't have any connections to the server. If not - what is the recommended way of handling this? I was thinking of adding a singleton service that keeps count, but am unsure if this would work at scale, especially with the SignalR service.
Thanks.
1) Better use the Azure SignalR.
2) Use it with the hub.
3) If you use Azure SignalR, you can just see it from the portal. In the code, whenever you use Azure SignalR or not, you can save the user Id in some var and count the connections. If you have multiple hubs and servers, you need to do more (if using redis-backplane for example).
My team is in the middle of deciding the architecture of our backend system:
Webserver A is an ASP.NET MVC application with ASP.NET Web API component, hosted in Azure Website.
Windows Service B is a self-hosted OWIN server that will periodically push notifications to clients who subscribes to the notification, hosted in Azure VM.
Windows Service C is a client that subscribes to notification from B, hosted in Azure VM.
Since we are more-or-less entrenched in .NET stack, we implemented B as SignalR server with C being the SignalR client. This part seems to work well.
Now comes a point where we also want A to subscribe to B, but I realize that it means an ASP.NET Web Server is going to act as SignalR CLIENT, instead of the typical scenario where it acts as SignalR server.
I presume we can initialize the SignalR connection in Global.asax and make the process ever-running to avoid AppDomain recycle. However, I feel a bit iffy when a Web Server is made to do something other than serving web requests. This solution also make the web server not stateless since it needs to maintain the web socket connection alive.
Is there something fundamentally wrong with making an ASP.NET application a SignalR client? Is there any possible gotcha with this setup?
In Azure you cannot tell that your AppDomain will not recycle. Because of many reasons, it can restart itself to heal and then you will end up making a new connection to the SingleR server. Is that OK for you?
Also SingleR is mostly used in the Web Functionality improvement where polling and refresh on web clients is made simple. But as your requirement seems to be all a back end stuff, I would suggest you to go with any other event driven pattern. Check Azure Service Bus topic/subscription model to have different components listen to various events and act accordingly.
Here is my situation:
I have a 4-tier web application consisting of browser, web server, application servers and database.
Browser and application server should communicate in a RPC-style way.
The backend will run on windows machines, so I will use IIS as web server The application needs real time communication between application server and browser.
I want to use a SignalR connection for the communication between browser and web server. For the communication between web server and application server's I want to use a plain TCP connection.
I think this approach will enable me to send JSON messages between browser and application servers. But how can I realize a RPC communication?
Can I write a SignalR Hub, generate a JS proxy and bind the Hub to a TCP socket?
Here is a picture: https://www.dropbox.com/s/xeaja4dos4bgvbz/SignalR_Hubs_Stackoverflow.png
Nope. SignalR is based on HTTP not TCP directly. WebSockets is the closest thing to a raw tcp socket and it has the added benefit that it works over port 80.
I have a use case where we will have an ASP.NET MVC Server Application but it needs to talk over a persistent connection to a Windows service. It doesn't look like SignalR does this as it really wants talk Server to JavaScript browsers but I did notice .NET desktop libraries. Can it talk from a server to a Windows server? If not, is there a recommended way, TCP/IP or HTTP to have a persistent connection between the two? NetTcpBinding in WCF?
Yes, there is a SignalR client library for .NET that you can use in any old .NET app to talk to a SignalR server just like you can from JavaScript.
While there is a WebSockets binding for WCF, there is no binding that actually talks native SignalR which adds its own message framing on top of raw web sockets. So, while possible, it doesn't exist today and I wouldn't hold my breath for it ever being created.
Why not simply have a queue using RabbitMQ. And anytime the web need to talk to window service, it push a message into the queue while the window service listen to the queue