printit

this was a fun experimante in the 2023 ccc camp, people printed a lot of stickers.

live at > https://print.tami.sh

it currntly a mini obsession. it can do a few things and more to come.

• print images (dithered as its a b/w thing)
• print labels, with QR codes if url provided
• print masks for PCB DIY etching(!), use the transparent ones for best resualts (WIP)
• print text2image using stable diffusion API
• print cats

started as a fork of brother_ql_web and his brother_ql printer driver, this driver is maintained and developed by matmair

network access by the openziti/zrok projects

TBD

• wrap text for printing paragraphs
• ???
• profit

usage

Install uv:

uv sync
uv run streamlit run printit.py --server.port 8989

Or with pip:

pip install -r requirements.txt
streamlit run printit.py --server.port 8989

we use the zrok.io to secure a static url.

```bash
zrok reserve public 8989
zrok share reserved xxxxxx

systemd

add you service to keep it alive. change <user> with your username. or any path to the printit folder.

create at /etc/systemd/system/sticker_zrok.service

[Unit]
Description=sticker factory
After=network.target

[Service]
ExecStart=/bin/bash -c 'source /home/<user>/printit/venv/bin/activate &&  /usr/bin/uv run streamlit run printit.py --server.port 8989'
WorkingDirectory=/home/<user>/printit
Environment="PATH=/home/devdesk/<user>/printit/venv/bin/python"
Restart=always
User=<user>
Group=<user>
[Install]
WantedBy=multi-user.target

sudo systemctl deamon-reload
sudo systemctl enable sticker.service
sudo systemctl start sticker.service

#debug using
sudo journalctl -u sticker.service --follow
sudo journalctl -u botprint.service --follow

we use the zrok.io to secure a static url.

zrok reserve public 8988
zrok share reserved kjvrml0bxatq

you can also run a service for this.

windows

to get the brother_ql lib to detect the printer, you need to install a usb filter

• grab release from zdiag
• refresh device list
• install the filter 'lib-winUSB` ,replacing the ql-XXXX driver
• replug the printer

update streamlit

streamlit had made some update with handling widths, pip install --upgrade streamlit if you see something in the line of

Exception in tab Label: '<=' not supported between instances of 'str' and 'int'
Traceback (most recent call last):
  File "/home/pi/stikka-factory/printit.py", line 304, in <module>
    label_module.render(
  File "/home/pi/stikka-factory/tabs/label.py", line 256, in render
    st.image(img, width='stretch')
  File "/home/pi/printit/venv/lib/python3.11/site-packages/streamlit/runtime/metrics_util.py", line 410, in wrapped_func
    result = non_optional_func(*args, **kwargs)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/pi/printit/venv/lib/python3.11/site-packages/streamlit/elements/image.py", line 154, in image
    WidthBehavior.ORIGINAL if (width is None or width <= 0) else width

Refactoring Summary

Configuration Management

• Created config.toml in workspace root for all application settings (non-sensitive)
• Moved settings from secrets.toml to config.toml: title, label_type, history_limit, items_per_page, queue_view, txt2img_url
• secrets.toml now contains only API keys (cat_api_key)

Code Organization

• Extracted image processing utilities into image_utils.py
• Extracted printer handling utilities into printer_utils.py
• Updated printit.py to import from utility modules instead of defining functions locally

UI/UX Improvements

• Updated all st.image() calls to use use_container_width=True for consistent responsive behavior, updating streamlit is maybe needed.

Key Files Modified

• config.toml - Settings file
• image_utils.py - Image processing functions
• printer_utils.py - Printer handling functions
• printit.py - Main app (refactored)
• tabs/*.py - Tab modules (updated imports)

Privacy mode

• disables history tab
• deletes labels

Disable sleep

To prevent the printer going to sleep mode use brother_ql installed on the host. You may need to activate the venv to do that.

1. Discover the printer with brother_ql discover, it returns something like Found compatible printer QL-600 at: usb://0x04f9:0x20c0/000H2G258173 were usb://0x04f9:0x20c0/000H2G258173 is the printer id

2. Set the power-off-delay to 0: brother_ql -p <PRINTER ID> configure set power-off-delay 0. You can check the set value brother_ql -p <PRINTER ID> configure get power-off-delay