Graphql subscriptions via sse via proxy when event-streams are not supported

[dennemark]

Hi,

we have clients who cannot use graphql subscriptions when we use SSE. The endpoint just stays Pending in network tab of developer tools in browser.
Now I was able to reproduce this by using mitmproxy. mitmproxy does not support event-streams. I assume our clients will have the same issue.
I tried via distrinct and single connection of graphql-sse as described on docs
Did anyone stumble over this before? We are considering changing to websocket, but SSE seemed nicer.

It also seems to be difficult to have some fallback if subscriptions or specifically SSE or WS are not supported.

Kind regards

[dennemark]

The problem might be that the proxy waits for content since content-length is not defined. So connection stays pending. At least this is what is described here: https://dev.to/miketalbot/server-sent-events-are-still-not-production-ready-after-a-decade-a-lesson-for-me-a-warning-for-you-2gie

The solution in that case was, to disconnect event streams every now and then for clients who cannot keep the connection alive. That way long-polling can be established as fallback.

I haven't implemented this yet, but I am a bit surprised there are no resources on this here on how to get around this issue.