nix-infra/config/hosts/ptouch-print-server/forcecommand-lpr-wrapper/forcecommand-lpr-wrapper.py
June c97f169b77
Add print server for label printer to have it easily usable via SSH
Add and configure a print server for the Brother P-touch QL 500 label
printer, so that it can be easily used via SSH.

Do the following to make that work:
- Configure the print server host.
- Package printer-driver-ptouch to have a working driver for the label
  printer.
- Configure CUPS.
- Add a script "forcecommand-lpr-wrapper", which works together with the
  ForceCommand sshd_config option and wraps lpr to provide an easy
  interface to use the Brother QL 500 label printer via SSH.
- Add a print user and configure SSH to have the
  "forcecommand-lpr-wrapper" script accessible without a password using
  the print user via SSH.
2024-04-14 18:46:51 +02:00

84 lines
2.9 KiB
Python

#!/usr/bin/env python3
# A script for usage with the ForceCommand sshd_config option.
# It calls lpr with some standard arguments, but also parses
# SSH_ORIGINAL_COMMAND to potentially provide a different set of arguments to
# lpr.
#
# This wrapper is written for interacting with the Brother QL 500 label printer.
#
# The following options can be provided as an SSH command and this script will
# then pass them to the lpr call: <MediaType> <PageSize>
# - MediaType can be one of:
# - Labels
# - Tape (this is the default)
# - PageSize can be one of:
# - 12mm
# - 12mm-circular
# - 17x54mm
# - 17x87mm
# - 23x23mm
# - 24mm-circular
# - 29mm
# - 29x90mm
# - 38mm
# - 38x90mm
# - 50mm
# - 54mm
# - 58mm-circular
# - 62mm
# - 62x29mm
# - 62x100mm
# - Custom.WIDTHxHEIGHT (with WIDTH and HEIGHT needing to be either one to
# three digits)
# - label-wide (this being a convenience alias for Custom.62x35mm and it also
# being the default)
# - label-item (this being a convenience alias for 38x90mm)
#
# So using these options in a complete setup would look like this for example:
# cat label-item.pdf | ssh print@ptouch-print-server.z9.ccchh.net labels label-item
# This being equivalent to:
# cat label-item.pdf | ssh print@ptouch-print-server.z9.ccchh.net Labels 38x90mm
#
# The options are case-insensitive.
#
# The options are derived from: lpoptions -p Brother-QL-500 -l
import os, re, subprocess
mediaType = "Tape"
pageSize = "Custom.62x35mm"
def parseGivenOptions():
givenOptionsString = os.environ["SSH_ORIGINAL_COMMAND"]
givenOptionsIterator = iter(givenOptionsString.split(" "))
givenMediaType = next(givenOptionsIterator, "")
givenPageSize = next(givenOptionsIterator, "")
global mediaType
if givenMediaType.lower() == "labels":
mediaType = "Labels"
elif givenMediaType.lower() == "tape":
mediaType = "Tape"
global pageSize
pageSizeRegex = re.compile(r"^((12mm(-circular)?)|(24mm-circular)|(58mm-circular)|(((17x(54|87))|(23x23)|((29|38)(x90)?)|(62x(29|100))|50|54|62)mm))$", re.ASCII | re.IGNORECASE)
pageSizeMatch = pageSizeRegex.match(givenPageSize)
pageSizeCustomRegex = re.compile(r"^custom\.(\d{1,3})x(\d{1,3})$", re.ASCII | re.IGNORECASE)
pageSizeCustomMatch = pageSizeCustomRegex.match(givenPageSize)
if givenPageSize.lower() == "label-wide":
pageSize = "Custom.62x35mm"
elif givenPageSize.lower() == "label-item":
pageSize = "38x90mm"
elif pageSizeMatch:
pageSize = givenPageSize.lower()
elif pageSizeCustomMatch:
width = pageSizeCustomMatch.group(1)
height = pageSizeCustomMatch.group(2)
pageSize = "Custom.{}x{}".format(width, height)
if "SSH_ORIGINAL_COMMAND" in os.environ:
parseGivenOptions()
subprocess.run(["lpr", "-P", "Brother-QL-500", "-o", "MediaType={}".format(mediaType), "-o", "PageSize={}".format(pageSize)])