LGBATTERY

System tray battery indicator for Windows Logitech devices. BECAUSE LOGITECH WON'T FOR SOME REASON.

WHAT ITS DOING

It uses the Python websockets library to watch for battery changed notifications from LG Hub - yeah, sorry, you'll still need that.

It puts an icon in the system tray after extracting the battery level icons it needs from C:\Windows\SystemResources\wpdshext.dll.mun These are saved in %APPDATA%\lgbattery.

On first run it'll display the icon with a question mark until you right click the tray icon and select your device which will cause it to get the battery level immediately.

Battery level is shown as a tooltip on the system tray icon which also changes depending on the battery level.

After that it'll save the selected device in %APPDATA%\lgbattery\config.ini so it'll pick it up on restart.

if you want, you can add a level_file entry to the prefs. This will cause the battery level to be written to that file, in case you want to display it in 72pt Trebuchet MS on the desktop using the (now dead) Samurize or something.

PREFERENCES

Preferences are stored in %APPDATA%\lgbattery\config.ini as a regular INI file. entries are as follows, under the [PREFS] section.

Name	Description
selected_device	Logitech ID for the device being monitored. Updated by the application when item selected from system tray rigt click
level_file	Full path to a text file that the application will create/update when the battery level changes
log_level	One of DEBUG, INFO, WARNING (default), ERROR or CRITICAL affecting the verbosity of logging.
log_file	File name (no path) for a text file to receive the logging output. File is created in %APPDATA%\lgbattery. If not present, logging is done to console.

IMPROVEMENTS

• The selected device is not ticked (checked: US) when selected. This is a limitation of the infi.systray library so if they add that functionality there I'll update this program.
• Linting
• Security scan
• GitHub Actions

CREDITS

Authors of all the libraries used (obviously) also @andyworld for LGSTrayBattery. I'd have just used that but it kept crashing for me, so I looked at the code as documentation for how to call the Logitech websockets API.

APOLOGIES

There are probably many threading crimes committed in this code. I have zero experience with websockets or Python asyncio. Debug Duck is now in rehab.

---

Build

Built on Python 3.12.0. From PowerShell:

python -m venv .venv
.\.venv\Scripts\Activate.ps1
pip install -r .\requirements.txt
pyinstaller --hidden-import pkg_resources --hidden-import infi.systray --onefile --noconsole .\lgbattery.py

Then enjoy .\dist\lgbattery.exe

LGHUB API

From a combination of black-box poking about and the author cited above. SysInternals strings utility revealed these listed endpoints.

Connecting to the API

1. Open a web socket to ws://localhost:9010 with the following headers:

   Header	Value
   Origin	file://
   Pragma	no-cache
   Cache-Control	no-cache
   Sec-WebSocket-Extensions	permessage-deflate; client_max_window_bits
   Sec-WebSocket-Protocol	json

ENUMERATING DEVICES

1. Send the following request to get a list of devices:

   {
       "msgId": "",
       "verb": "GET",
       "path": "/devices/list"
   }

Response is:

• an JSON array of objects, one per device under message['payload']['deviceInfos'].
• message['payload']['deviceInfos'][]['capabilities']['hasBatteryStatus'] is True if the device has a battery that can be queried.
• message['payload']['deviceInfos']['id'] seems not to be unique over time, so no good for saving which device is being monitored. Original release used this & was changed to use extendedDisplayName instead as user unlikely to have multiple instances of the same peripheral.

WATCHING FOR BATTERY CHANGE

1. Send the following request: It looks like the subscription is cancelled when you get a reply, so needs to be sent every time you get a response back, not just once at the start.

   {
       "msgId": "",
       "verb": "SUBSCRIBE",
       "path": "/battery/state/changed"
   }

2. Receive the following response and parse

   {
       "msgId": "50d84cf9-13c6-4376-83c9-01b4f0655915",
       "verb": "BROADCAST",
       "path": "/battery/state/changed",
       "origin": "backend",
       "payload": {
           "@type": "type.googleapis.com/logi.protocol.wireless.Battery",
           "deviceId": "dev00000007",
           "percentage": 74,
           "mileage": 24.9428902,
           "maxLifeSpan": 33.7066078,
           "charging": False,
           "consumption": {
               "value": 7.03438568,
               "details": {
                   "system": 5.92066669,
                   "sensor": 4.28,
                   "mcu": 1.64066672,
                   "roller": 0,
                   "reportRate": 0,
                   "lighting": 5.4763155,
                   "volume": 0
               },
               "useMw": True
           },
           "simpleBattery": False,
           "criticalLevel": False,
           "chargingError": False,
           "componentType": "INVALID_TYPE",
           "fullyCharged": False
       }
   }

   This response only has the deviceId which isn't unique over time, so when we save and load the prefs we use extendedDisplayName, then keep track of the selected device as an object which carries the extendedDisplayName and the deviceId