# $connection_upgrade — WebSocket upgrade helper for the maven.<domain> block
# in nginx.conf. Install this ONLY if your nginx does not already define
# $connection_upgrade somewhere in the http context.
#
# It is a separate file because nginx treats a duplicate `map` directive as a
# fatal configuration error, not a warning: if this block were inside
# nginx.conf and your setup already had one (nginx-panel and most WebSocket
# recipes ship one), the next `nginx -s reload` would fail the config test and
# nginx would refuse to come back up — taking every other site on the box down
# with it, not just maven.
#
# Check before installing:
#     grep -rn 'connection_upgrade' /etc/nginx/
# Nothing? Drop this in /etc/nginx/conf.d/ and reload. Something already there?
# Skip this file entirely; nginx.conf works as-is.
#
# Verify either way before reloading:
#     nginx -t
map $http_upgrade $connection_upgrade {
    default upgrade;
    ''      close;
}