jakecoppinger / whos-in-this-room-matrix-bot

Announce Matrix room joins/leaves/members to Signal users in bridged chats with relay mode

Who's In This Room Matrix Bot

Keep Signal users in your Matrix group chats in the loop!

TLDR: In Matrix <-> Signal bridged chats with relay mode enabled, announce Matrix room joins/leaves and summarise the room members when a Signal user joins (because they can't see)

To ask questions or give feedback please join #whos-in-this-room-bot-discussion:jakecopp.chat!

What is a bridged chat with relay mode?

Matrix is a chat protocol which supports bridges to other chat apps. Some of these bridges support "relay mode", where you can add people on the other chat app into the same chat that Matrix users are in.

In this case, the members of the other chat app can't see who the Matrix users are - Matrix solves this by "double puppetting" the bridged users (almost like "mocked" users), but just about all other chat apps don't support this.

What this bot does

Your Signal guests have probably experienced the confusion where they don't know who else is in the chat (using Matrix).

When this bot is added to a Matrix room, it will announce:

• Who the room members are when a new Signal user joins
• When a Matrix user joins or leaves, who that Matrix user was.

Examples

Specifically, this is the message sent when the bot is added to a room:

👋 Hello, I'm the Who's In This Room Bot 😃

Each time a Signal user joins the chat I'll send a message saying how many people are in the chat on the Matrix side (as they can't see). I'll also let them know when Matrix users join or leave.

Currently, there are 24 people in this chat in total; 14 on Matrix and 10 on Signal. The Matrix users are ...,... and ....

For questions or feedback jump into #whos-in-this-room-bot-discussion:jakecopp.chat.

When a Signal user joins the room, this is (an example) message the bot sends:

👋 Hello, I'm a bot 😃 This chat is bridged between Signal & Matrix.

There are ... people in this chat in total; ... on Matrix and ... on Signal. The Matrix users are ..., ... and ....

To learn more see matrix.org/bridges/ or ask your host.

Local development setup

• Run yarn
• Run yarn build

Running in prod

• yarn
• yarn build
• yarn start

Further work

I'm very open to adding support for more platforms apart from Signal. PRs very welcome!

License

GNU AGPLv3. See LICENSE