util.startup: Support systemd Type=notify service type
This lets Prosody report its lifecycle status to systemd, so it knows
when Prosody has completed its startup, when it's reloading and shutting
down.
Both Type=notify and Type=notify-reload is supported
Example systemd .service configuration snippet:
[Service]
Type=notify
local st = require "prosody.util.stanza";
local xmlns_csi = "urn:xmpp:csi:0";
local csi_feature = st.stanza("csi", { xmlns = xmlns_csi });
local change = module:metric("counter", "changes", "events", "CSI state changes", {"csi_state"});
module:hook("stream-features", function (event)
if event.origin.username then
event.features:add_child(csi_feature);
end
end);
function refire_event(name)
return function (event)
if event.origin.username then
event.origin.state = event.stanza.name;
change:with_labels(event.stanza.name):add(1);
module:fire_event(name, event);
return true;
end
end;
end
module:hook("stanza/"..xmlns_csi..":active", refire_event("csi-client-active"));
module:hook("stanza/"..xmlns_csi..":inactive", refire_event("csi-client-inactive"));