LitraWeb

LitraWeb is a simple web interface and API for the Logitech Litra Glow, written in Go with an HTML/JS/CSS/Bootstrap front end.

It makes use of the derickr/go-litra-driver project which offers a Go driver for the Logitech Litra Glow.

It enables the Litra Glow to be plugged into a Linux PC such as a Raspberry Pi, and the web interface accessed remotely to control the light.

In my case this is useful since I use the light for video calls, and my work laptop doesn’t permit 3rd party software. You may have your own use case, and if so I hope it’s more interesting than mine.

Functionality

LitraWeb offers the same basic set of functionality as the Go driver:

  • Turning the light on/off
  • Setting brightness
  • Setting colour temperature

Additionally, the named presets provided by Logitech in the official software have been implemented in LitraWeb.

Installation

For the most part, simply plug in your light, then compile and run the application. It will listen on port 8080 by default.

To run as a non-root user on Linux, you’ll need to set up the following udev rule in /etc/udev/rules.d/82-litra-glow.rules:

SUBSYSTEM=="usb", ATTRS{idVendor}=="046d", ATTRS{idProduct}=="c900", MODE:="0666", GROUP="plugdev"

Then load the new rule:

udevadm control --reload-rules && udevadm trigger

And finally, (re-)plugin your light.

Docker

You can also run in Docker, though the container will need to be run in privileged mode.

An example docker-compose.yml file is included in the Repo, just make any modifications as you wish and remove the .sample extension.

Build Docker Image

Usage

The web interface can be accessed at the root of port 8080 on your device, e.g. http://127.0.0.1:8080/

The API offers the following endpoints:

Endpoint Purpose Request Variable Input
/api/on Turn the light on GET
/api/off Turn the light off GET
/api/brightness/:var Set the brightness GET :var – brightness value Range: 0-100
/api/temperature/:var Set the temperature GET :var – temperature value Range: 2700-6500 (in increments of 100)

Limitations

Rome wasn’t built in a day, but this software was. Use it with care, and don’t consider it secure or production-ready.

The following are limitations at the moment which I’d like to be able to address:

  • Only a single light is supported.
  • The presets are a guess based on the slider locations in Logitech’s official software. If anyone finds the actual values they use then feel free to correct mine.
  • It isn’t possible to read the state of the Litra Glow, in order to pre-set the toggles and sliders to their current values.
  • I’ve only tested on Linux, not sure if this will work on Windows/Mac.
  • No form of API authentication.

Pull Requests

…are very welcome. I am not a Go developer, just a systems guy with a light behind my webcam. Please help fix my code ?

GitHub

View Github