title: ASP.NET Core keep-alive to ESP32
body: <p>I would like to have ASP.NET Core based website with communication to ESP32 (microcontroller with program based on Arduino code) which would have keep-alive connection. Something like serial-port without cable over network. I figured out that websocket might work and be the best solution (or not?). ESP32 doesn't support SignalR so I have to go raw websocket. I found only middle-ware solutions without support to be called from controller.</p>
  
  <p>Idea is: Keep-alive connection between ESP32 and ASP.NET Core website. User can go to website and trigger action (from browser/api) which will send data to ESP32. Website is public-part. Browser and ESP32 are closed parts (I mean.. no public ip address). Also I would like to send data immediately after action is triggered. It would be nice if ESP32 would receive data within 3 seconds.</p>
  
  <p>Is websocket correct idea? Can you show me or direct me how to send data from action to websocket client? I couldnt find enough informations how to make it.</p>