This Ubuntu-based Docker image runs a CUPS instance that is meant as an AirPrint relay for printers that are already on the network but not AirPrint capable. I'm using it on a Synology NAS because the built in server doesn't work properly with my printers. The local Avahi will be utilized for advertising the printers on the network.
This is also an excuse to dip my toes into GitHub/Docker more, so why not? Hopefully someone else finds this useful.
Enable Bonjour service discovery needs to be marked under Control Panel>Network>DSM Settings /config: where the persistent printer configs will be stored/services: where the Avahi service files will be generatedCUPSADMIN: the CUPS admin user you want createdCUPSPASSWORD: the password for the CUPS admin user631: the TCP port for CUPS must be exposedCUPS will be configurable at http://[diskstation]:631 using the CUPSADMIN/CUPSPASSWORD when you do something administrative.
If the /services volume isn't mapping to /etc/avahi/services then you will have to manually copy the .service files to that path at the command line.
printers.conf immediately when making changes even though they're live in CUPS. Therefore it will take a few moments before the services files update