MRPC

Experimental Discord Mobile Rich Presence (Android)

How does it work?

It's pretty simple.

• Connect to the Discord Gateway as a normal Discord Client.
• Send Identify and Update Presence.

Custom image support + gif

MRPC now supports setting custom image through 2 links:

• https://media.discordapp.net (resolves from mp:path/to/image)
• https://cdn.discordapp.com (resolves from ../../path/to/image)

In late 2021(?), Discord allowed activity to specify media proxy image, which opens a way to set custom image. However, there is another trick that has not been used before:

• By default, Discord parses the input as application_assets (unless it is set to media proxy with mp: prefix)
• Setting the asset object to test results in https://cdn.discordapp.com/app-assets/application-id/test.png
• It does not verify anything there. This way, we can put ../.. to escape the path, then we can set anything such as an animated emoji right here, finally # at the end to exclude .png.
• Setting the asset object to ../../emojis/emoji-id.gif# results in https://cdn.discordapp.com/app-assets/application-id/../../emojis/emoji-id.gif#.png which then gets resolved to https://cdn.discordapp.com/emojis/emoji-id.gif

Notes

• MRPC parses the image link automatically, so you just need to paste the link and it will work out of the box. You can only use image link from domains listed above.
• Rate limiting is not yet handled.
• This app uses the Discord Gateway instead of OAuth2 API (which I can't even find the documentation for the activities.write scope), so this might not be safe. Use this at your own risk.
• Zlib compression is not yet used, due to the current using library doesn't correctly handle it(?).

License

Apache License 2.0.

Third party libraries and their licenses

• gson: Apache License 2.0.
• Java-WebSocket: MIT License.
• slf4j-android: MIT License.