butopea/printnode-docker repository overview

⁠Printnode Print Server Image

⁠Overview

Docker image including CUPS print server, printing drivers and Printnode client to print from web application directly to printers.

⁠Run the print server

version: "3"
services:
    printnode:
        image: butopea/printnode-docker
        restart: unless-stopped
        ports:
            - "631:631"
            - "8888:8888"
        devices:
            - /dev/bus/usb:/dev/bus/usb
        environment:
            - CUPSADMIN=print
            - CUPSPASSWORD=print
            - [email protected]
            - PRINT_CLIENT_PASSWORD=printprint
            - TZ="Europe/Budapest"
        volumes:
            - <persistent-config-path-cups>:/etc/cups
            - <persistent-config-path-printnode>:/root/.printnode/printnode

⁠Parameters and defaults

• cmd: by default it starts printnode with following options --computer-name $PRINTNODE_HOSTNAME --headless --web-interface --use-enviroment-variables. Add cmd /usr/local/PrintNode/PrintNode --your-options to add more but keep the default ones within command to be functional
• ports: default cups network port 631:631. Recommended to change if host has alreacy another cups server running. 8888 is the webinterface for Printnode
• devices: used to give docker access to USB printer or scales. Default recommendation is to pass the whole USB bus /dev/bus/usb, in case you change the USB port on your device later. change to specific USB port if it will always be fixed, for eg. /dev/bus/usb/001/005. Need to check for USB weighting scales
• volume -> adds a persistent volume for CUPS config files and Printnode config files if you need to migrate or start a new container with the same settings. You can also mount your own cupsd.conf file or printnode config file this way.

Environment variables that can be changed to suit your needs

⁠Add printers to the Cups server

1. Connect to the Cups server at http://127.0.0.1:631⁠ (or the port you have exposed)
2. Add printers: Administration > Printers > Add USB printers or remote network printer
3. They will be automatically picked up by Printnode

Note: The admin user/password for the Cups server is by default print/print. Can be customized via env vars.

⁠Add USB weighing scales to Printnode

First, check out if your scale is supported⁠ by Printnode.

This client accesses USB devices via Linux's "hidraw" subsystem. On the Linux distros PrintNode has tested the Client on, the default permissions for hidraw devices are 0x600, i.e. access to USB HID scales is for root users only.

You can check the permissions currently assigned to HID devices on a system as follows:

ls -al /dev/hid*

Access to USB scales or other hidraw devices as an unprivileged user is controlled with udev rules which can whitelist some or all devices.

The included executable "udev-rule-generator" can generate udev rules specifically for your system and connected devices. In addition to this if you run "udev-rule-generator" as the root user it will also write the rules file to the correct location and apply the changes. "udev-rule-generator" is safe to run multiple times. You should run "udev-rule-generator" the first time you plug a new USB scale into a computer.

Using "udev-rule-generator" is the easiest way to create and manage udev rules.

sudo ./udev-rule-generator

To whitelist all USB hidraw devices for all users, add the following text to /etc/udev/rules.d/10-scales.rules:

KERNEL=="hidraw*", SUBSYSTEM=="hidraw", MODE="0666"

⁠Credits

Inspiration has been drawn from anujdatar/cups-docker⁠ and olbat/cupsd⁠