CUPS snap is working now (tested printing from LibreOffice snap through CUPS snap):
- CUPS snap now checks whether port 631 is busy. If it is not busy it starts CUPS on port 631, otherwise on 10631.
- cups-browsed startup waits for CUPS startup having selected the port, to assure correct connection of the snap’s CUPS and cups-browsed
- It is not recommended to run both the system’s (Debian-package-based) and the snapped CUPS on production systems, but for development setups this is possible.
- If a system is only running the snap’s CUPS, this CUPS is available through port 631 and both Debian-package-based and snapped applications can print on it.
- The snap still needs manual connection to Avahi and USB interfaces (on core also to home dir intrerface).
- Connected to Avahi interface the snapped CUPS finds and sets up IPP (driverless) printers automatically, using its cups-browsed.
- Users in “adm” group can do administrative tasks using the command line utilities of the snap (they use the snap’s domain socket by default), admin via localhost:631 (system’s utilities) does not work.
- The snap uses now the up-to-date upstream versions: CUPS 2.2.8, cups-filters 1.21.2, and to fulfill the dependencies of cups-filters QPDF (8.2.1) is nowalso included.
- Cleaned up warnings in snap build process
- Updated README.md
Next steps:
- Automatic connection of all interfaces (Request)
- Addition of ippusbxd for auto-setup of driverless USB printers (Needs support for systemd templates).
- If possible/needed: Have “lpadmin” group for administrative tasks (Thread: Multiple users and groups in snaps)
- Get admin via localhost:631 to work (Thread: User authentication in snapd)