Open Source implementation of GOG Galaxy Communication Service for SDK bundled with GOG games.

Open Source implementation of GOG Galaxy's Communication Service

This project aims to implement calls made by game through SDK.
Note: that means it can't and won't replace Communication Service in official client

This will provide minimal and platform-agnostic SDK. For use in game launchers like Heroic or Lutris

Project is continuation of Yepoleb's work https://gitlab.com/Yepoleb/comet/ but in ~~Python~~ now in Rust

Supported Requests

Game

Overlay

This includes calls made to be forwarded to game process

How to use

Comet integration in game launchers

Heroic - ✅ an experimental feature enabled by default (as of 2.15.0)
Lutris - ❓ planned, no ETA
Minigalaxy - ❓ open for Pull Requests

For manual instructions see running

Some client SDK versions require Windows service to be registered, refer to dummy service

Authentication

You need to obtain access_token, refresh_token and user_id either manually, or by importing them:

Via Heroic Games Launcher

Via Lutris

Via wyvern (CLI)

Via gogdl (CLI)

If GOG authentication has never been performed in Heroic on the current user, create the expected directory:

mkdir -p $HOME/.config/heroic/gog_store

Then, run the command:

./bin/gogdl --auth-config-path $HOME/.config/heroic/gog_store/auth.json auth --code

Obtain the code by logging in using this URL, then copying the code value from the resulting URL:

https://login.gog.com/auth?client_id=46899977096215655&layout=galaxy&redirect_uri=https%3A%2F%2Fembed.gog.com%2Fon_login_success%3Forigin%3Dclient&response_type=code

Running

comet --token "" --refresh_token "" --user-id  --username

Or if you are using Heroic/gogdl

comet --from-heroic --username

Or Lutris

comet --from-lutris --username

Or wyvern

comet --from-wyvern --username

Or use the shortcut script provided for non-Steam shortcuts. See the Steam Deck Usage Guide.

Configuration

You can adjust basic overlay settings with comet configuration file.
File locations:

Windows - %APPDATA%/comet/config.toml
Mac - ~/Library/Application Support/comet/config.toml
Linux - $XDG_CONFIG_HOME/comet/config.toml

Default configuration file is as follows

[overlay]
notification_volume = 50  # value from 0 to 100
position = "bottom_right" # position where notifications are shown: top_left top_right bottom_left bottom_right

# Controls chat message notifications
[overlay.notifications.chat]
enabled = true
sound= true

# Controls notifications when friend becomes online
[overlay.notifications.friend_online]
enabled = true
sound= true

# Controls notifications when someone sends you a friend invititation
[overlay.notifications.friend_invite]
enabled = true
sound= true

# Controls notifications when friend starts playing a game
[overlay.notifications.friend_game_start]
enabled = true
sound= true

# Controls notifications when someone sends you a game invite
[overlay.notifications.game_invite]
enabled = true
sound= true

Contributing

Join Heroic Discord and reach out to us on special thread

Here you can find a blog post about setting up environment for tracing the Communication Service calls (involving Proxifier and custom mitmproxy)

Reverse engineered protobuf definitions are available here: https://github.com/Yepoleb/gog_protocols

Debugging SDK Client

In order to dump logging from SDK client (the game) download GalaxyPeer.ini, when placed next to game .exe it will write GalaxyPeer.log when the game is running.

> [!WARNING]
> Proceed with caution, the log may contain sensitive information, > make sure to remove such data before sharing the file with others.

Sponsoring

If you want to contribute financially you can do so via my Ko-Fi.
You can also use any of the options to support Heroic

Comet Paweł Lidwin

README