Synapse broadcast module

Important

🚧 This repo hosts a POC and is not meant to be used

Use case 📖

• a user is part of a private federation in which, for some reason, has several accounts on different homeserver
• there's a 3rd party service linking the user and its MXID
• the user wants all the conversations of all his/her MXIDs to be synchronized
• if a message is read (or sent) with a MXID it should be marked read for every MXID

Ideas 💡

The Tchap way

• A users creates an account on any of the federation servers
• At login, Element (or other clients), calls a service to select the right server to connect to, depending on a 3PId the code here
• In the interface the displayed name is preferred over the MXID

Pros 👍

• Already implemented with Tchap
• Unique account with federated architecture

Cons 👎

• If a server closes, accounts have to be migrated, users probably lose their messages
• Not obvious to implement for non-Element clients
• More complicated than centralized architecture with the constraints of the federated one

With some new EIMIS modules

These requirements could be met with a Synapse module :

• when a user is invited to or creates a room, all its MXID are invited
• when a message is read, it should be marked as read for all the MXID

Limitations 🚧

• The receipts part should not be modified like this, but it's just a POC 🤷🏻

Directory

For this POC a stubb directory has been created using grist. For CORS purpose, a synapse module acts as a proxy.

Run the POC 🚜

Prerequisites

• docker / docker compose installed
• traefik and domain name configured

Start the stack

• fill the .env file

  TRAEFIK_NETWORK=
  DOMAIN=
  USER=("admin_matrix" "alice" "bob")
  SUB_DOMAIN_1=kiwi
  SUB_DOMAIN_2=litchi
  DIRECTORY_URL=https://something-that-returns-an-array-of-mxid?mxid=

DIRECTORY_URL : an url that, concatenated with a MXID, should return a json array of linked mxid.

• start the stack

  chmod +x *.sh  
  ./init.sh
  docker-compose up -d

• register users (configure in.env) in both servers (password=username, all admin : YOLO!)

  ./register-users.sh

• if you want to reset the stack (erase database)

  ./reset-stack.sh

docker-compose logs etc... and go to your domain, login, create room, invite user and try it out!