p910nd-ogra

A small printer daemon intended for diskless platforms that does not spool
to disk but passes the job directly to the printer. Normally a lpr daemon on
a spooling host connects to it with a TCP connection on port 910n
(where n=0, 1, or 2 for lp0, 1 and 2 respectively).

p910nd is particularly useful for diskless platforms.
Common Unix Printing System (CUPS) supports this protocol, it's called the
AppSocket protocol and has the scheme

 socket://remotehost:PORT

Windows and Mac Os X (via CUPS) also supports this protocol.

You need to allow p910nd access to the usb printer by connecting the raw-usb
snap interface

 snap connect p910nd-ogra:raw-usb

... else the daemon will not start.

optionally you can configure the following settings though snap set commands:

 snap set p910nd-ogra device="/dev/usb/lp0"

 snap set p910nd-ogra bindaddr="192.168.1.5"

additionally enabling/disabling bidirectional communication can be done with:

 snap set p910nd-ogra bidirectional=true

 snap set p910nd-ogra bidirectional=''

Note: some printers tend to automatically suspend the USB bus, to prevent
/dev/usb/lp* from going away after a while, set usbcore.autosuspend=0 on your
kernel cmdline.