zmcontrol dispatches straight onto the control object with
$control->$command(...). A monitor's actions and ui buttons are configured
independently of its control protocol, so nothing stops a LightOn action
pointing at a protocol with no lightOn, and Perl kills the control server with
"Can't locate object method".
Swapping a camera for a different make produces exactly that. A monitor whose
AMLink camera was replaced by an ONVIF one kept its LightOn and LightOff
actions, and ONVIF has neither, so the first alarm after the protocol change
would have taken the control server down for that monitor.
Check can() before dispatching, log which monitor and command need attention,
and answer a caller that asked for a response rather than leaving it hanging.
Direct protocol mode gets the same check, as a Fatal, since there the command
came from the command line and is a typo worth reporting.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01UvTCzCbvGt8xKQRNCSA7o8
