HTTP/1.1 subscriptions never receive data (nginx proxy buffering)

[lucidfox]

Subscribing to a topic as a stream (GET /<topic>/json?poll=false, also /sse and /raw) never returns anything over HTTP/1.1 on my ntfy instance: the TLS handshake and request complete, but nothing comes back (not even the response headers). The same request over HTTP/2 works and delivers the open event and a keepalive every 45 seconds. Short requests over HTTP/1.1 are fine (poll=1, /v1/health, publishing).

This is for a private ntfy topic, and you can reproduce the issue like this:
curl -sN --http1.1 -m 120 -H "Authorization: Bearer $TOKEN" "https://ntfy.example.com/mytopic/json?poll=false"
-> nothing for 120 seconds
curl -sN --http2 -m 120 -H "Authorization: Bearer $TOKEN" "https://ntfy.example.com/mytopic/json?poll=false"
-> {"event":"open",...} at once, then a keepalive every 45 s

ntfy's reverse-proxy docs (https://docs.ntfy.sh/config/#nginxapache2caddy) require proxy_buffering off (and proxy_request_buffering off) for this reason. Clients that speak HTTP/1.1, such as Python's httpx or the ntfy CLI in some setups, hit this; browsers and curl usually negotiate HTTP/2 and don't.

Would it be possible for the ntfy package's nginx location to get proxy_buffering off?

[james]

Hello @lucidfox
Thanks for reporting. An app update will be available soon that will fix this issue.

[lucidfox]

Thanks for picking this up @james