pub const DRAIN_TIMEOUT: Duration;Expand description
How long a connection has to finish once shutdown has been asked for.
Graceful shutdown means finishing the request in flight — and one of the
requests this server serves, /{application}/{profile}/stream, is a
response body that never ends by design. Waiting on every body would mean
waiting for every subscriber to disconnect, so a rollout would hang on
exactly the clients that were paying attention.
So the drain has a deadline, and both serving paths hold to it. A
subscriber loses its stream and reconnects, which is what an
EventSource does by itself and what the Last-Event-ID rules exist
for; a fetch genuinely in flight has thirty seconds, which is far longer
than any endpoint here takes.