Install printlog-bridge on a Klipper Printer

Install printlog-bridge on the Printer

Part of the Log prints from Klipper guide.

In local mode, printlog-bridge runs on the printer's own host, next to Klipper and Moonraker: MainsailOS, FluiddPi, or any Klipper install with Moonraker. If you can't install software on the printer, or you want one bridge for several printers, run it in Docker instead.

Before you start

Python 3.9 or newer on the printer's host. Raspberry Pi OS Bullseye and later have it.
SSH access as the user Klipper runs as, such as pi. The installer refuses to run as root, and uses sudo to install the service.
The printer's number in 3D Print Log. Open the printer from the Printers page. Its number is the end of the address: 42 in https://www.3dprintlog.com/printers/42.
A personal API key, from the Personal API Keys page. See Connect to your account.

Install

On the printer's host, run:

cd ~ && git clone https://github.com/HoffmanEngineering/printlog-bridge.git
./printlog-bridge/install.sh

The installer asks for the API key (what you paste isn't shown) and the printer's number. Press Enter at either one to fill it in later. It then:

makes a virtualenv in ~/printlog-bridge-env and installs the bridge into it;
stores the API key in ~/.local/share/printlog-bridge/api_key, readable only by you;
writes ~/printer_data/config/printlog-bridge.cfg, next to printer.cfg, unless you already have one;
installs and starts a printlog-bridge systemd service;
adds printlog-bridge to ~/printer_data/moonraker.asvc, so Mainsail and Fluidd can restart it;
adds an [update_manager printlog-bridge] section to moonraker.conf, so updates show up in the update panel of Mainsail and Fluidd, and restarts Moonraker to load it;
copies the spool macros to ~/printer_data/config/printlog.cfg and adds [include printlog.cfg] to printer.cfg.

The installer doesn't restart Klipper, since that would end a print. Restart it yourself when the printer is idle (FIRMWARE_RESTART in the console) to load the spool macros.

Running install.sh again is safe. Its options:

Option	What it does
`--printer-data DIR`	Moonraker's data folder, when it isn't `~/printer_data`
`--printer-id N`	The printer's number in 3D Print Log, so it isn't asked for
`--venv DIR`	Where to make the virtualenv (default `~/printlog-bridge-env`)
`--moonraker-service NAME`	Moonraker's systemd service, when it isn't `moonraker`
`--no-macros`	Don't install the spool macros or include them from `printer.cfg`
`--yes`	Ask nothing. Fill in the config afterwards.

install.sh --help lists them too. The installer sets up one Klipper instance per host. To move it to another printer_data folder, uninstall it first.

Connect to your account

Until one-step pairing arrives (it's planned), the bridge signs in with a personal API key and needs to know which printer in 3D Print Log its prints belong to.

Create a key on the Personal API Keys page and copy it. Give each bridge its own key, so you can revoke one without stopping the others.
If you skipped the key during the install, store it now, and paste it when asked:
```
~/printlog-bridge-env/bin/printlog-bridge store-key
```
store-key keeps the key in ~/.local/share/printlog-bridge/api_key, readable only by you, and replaces any key already there.
If you skipped the printer's number, set printer_id in printlog-bridge.cfg. Mainsail and Fluidd can edit the file (under Machine), or edit it over SSH:
```
[printer voron]
printer_id = 42
socket = /home/pi/printer_data/comms/moonraker.sock
```
Restart printlog-bridge from the services menu in Mainsail or Fluidd, or run sudo systemctl restart printlog-bridge.

While its config needs fixing (no key, no printer_id), the service stops and waits for you rather than restarting itself.

Keep the key out of printlog-bridge.cfg

Moonraker lets anyone who can open Mainsail or Fluidd download every file in Klipper's config folder, including printlog-bridge.cfg. An api_key line there still works, but doctor warns about it. Run store-key to move it: it writes the key file and empties the line in the config.

The bridge looks for the key in this order: the PRINTLOG_API_KEY environment variable, then the key file, then api_key in the [bridge] section.

Check it

When both the key and the printer's number were given, the installer checks the setup with doctor before it finishes. Run the same check any time:

~/printlog-bridge-env/bin/printlog-bridge doctor
~/printlog-bridge-env/bin/printlog-bridge status

doctor checks the config, the API key, the computer's clock and the printer, and says what to fix. status shows what the running bridge is doing. Troubleshooting explains both.

In 3D Print Log, the printer's Edit Page now lists the bridge under Connections. Start a print and it shows up on your Print List as Printing.

Config file

The installer writes ~/printer_data/config/printlog-bridge.cfg, with one [printer <name>] section named after the host. Each printer is a section, so one bridge can watch several. After a change, restart printlog-bridge.

Section	Option	Default	What it is
`[bridge]`	`api_url`	`https://api.3dprintlog.com`	3D Print Log's API. Must be `https`.
`[bridge]`	`state_dir`	`~/.local/share/printlog-bridge`	Where the key file, the outbox, the log and the status live. `PRINTLOG_BRIDGE_STATE_DIR` sets it when this doesn't.
`[bridge]`	`trace`	`false`	Record every Moonraker message, to report a problem.
`[bridge]`	`allow_http_on_lan`	`false`	Allow plain `http` to a development API on your network. See the Docker page.
`[bridge]`	`api_key`		Works, but use `store-key` instead.
`[bridge]`	`slicer_settings`	`true`	`false` never reads the G-code file, so no slicer settings are recorded. Can also go in a printer's section.
`[printer <name>]`	`printer_id`		The printer's number in 3D Print Log. Required.
`[printer <name>]`	`socket`	`~/printer_data/comms/moonraker.sock`	Moonraker's socket, in local mode.
`[printer <name>]`	`url`		Moonraker's address, such as `http://192.168.1.50:7125`, in remote mode. Set `url` or `socket`, not both.
`[printer <name>]`	`moonraker_api_key`		Remote mode only, when Moonraker has `[authorization]` on and doesn't trust the bridge's computer.
`[printer <name>]`	`snapshots`	`true`	`false` never asks the webcam for anything.
`[printer <name>]`	`adapter`	`moonraker`	The kind of printer. Moonraker is the only one today.

The bridge looks for its config in this order: --config on the command line, the PRINTLOG_BRIDGE_CONFIG environment variable, ~/printer_data/config/printlog-bridge.cfg, then ~/.config/printlog-bridge/printlog-bridge.cfg. Every option is described in printlog-bridge.example.cfg.

Update

Updates show up as printlog-bridge in the update panel of Mainsail and Fluidd, next to Klipper and Moonraker. When a new version is out, the printer's Connections in 3D Print Log say so too. See Update.

Uninstall

./printlog-bridge/uninstall.sh

It removes the service and the virtualenv, and puts moonraker.conf, moonraker.asvc and printer.cfg back exactly as they were. It removes printlog.cfg too, unless you changed it. Your config and the state directory, including any prints not yet logged, are kept for a reinstall. Add --purge to remove those as well.