Server-Sent Events with Unity Web Request

Hello,

I'm trying to get a Server-Sent Event working with Unity, but with little luck. So far, this is the code that I have to try and get it to constantly listen for updates with:

Code (CSharp):

1.  
2. public IEnumerator ListenForChanges(string uri)
3.     {
4.         UnityWebRequest req = UnityWebRequest.Get(uri);
5.         req.SetRequestHeader("Accept", "text/event-stream");
6.         var response = req.SendWebRequest();
7.         while (!req.isDone)
8.         {
9.             Debug.Log("Text downloaded: " + req.downloadHandler.text);
10.             yield return new WaitForSeconds(1);
11.         }
12.     }
13.  

But this doesn't seem to be working. I am able to get one response from the function, but after that I get no other responses. Is there any way that I am able to get this to work, so that it constantly checks for updates and is able to stream them to the game?

I'm using Firebase Database as the back end, from where I am getting the data.

Thank you very much in advance.

 

Using HTTP you can typically send one request and get one response back, after that the connection is closed and you need to repeat from the top.

What you're trying to do requires a polling technique, where the client constantly sends requests to ask the server if there's any update. It's not the best approach but it can work for non real-time tasks.
Another possibility is to use websockets instead, which open a persistent connection between client and server and allows the server side to push events at any time.

There's no native Websocket support in Unity but it can be done via additional libraries such as websocket-sharp