THIS IS UNMAINTAINED!!!
PLEASE SEE https://github.com/witchent/matrix-puppet-signal
signal-bridge 
This is a Matrix bridge for Signal, messenger app by Open Whisper Systems.
It's based on the official Signal-Desktop Client that has been ported to Node.js with minor modifications. They are necessary to remove things that are related to Electron that provides the graphical interface. You can find that here: https://github.com/matrix-hacks/Signal-Desktop / https://github.com/matrix-hacks/node-signal-client
Features
- [x] Linking as a second device
- [x] Signal to Matrix direct text message
- [x] Matrix to Signal direct text message
- [x] Signal to Matrix group text message
- [x] Matrix to Signal group text message
- [x] Signal to Matrix image attachment message
- [x] Matrix to Signal image attachment message
- [x] Signal to Matrix file attachment message
- [x] Matrix to Signal file attachment message
- [x] contact list syncing
- [x] group syncing
- [x] show read receipts
- [x] send read receipts
- [x] show typing events
- [x] send typing events
requirements
You need an iOS and Android phone with an existing Signal account that you are willing to link with the Signal client in this bridge.
required software:
- Node.js
- yarn
Please verify if yarn -v outputs something like 1.17.3. If your output is ERROR: There are no scenarios; must have at least one. you have installed cmdtests instead of yarn. Please install yarn before you continue.
In the past we saw various issues with node versions different from the one that the official Signal-Desktop client uses. If you run into any issues you might try that version. The easiest way to change your version is using n. You can install it using npm install -g n and switch to Node.js 12.13.0 using n 12.13.0.
installation
clone this repo
cd into the directory
run npm install
Note: Run neither the installation command nor the bridge itself with root rights.
register/link with your signal mobile app
Before configuring the bridge with Matrix, you need to setup the Signal link with your phone. Open up your Signal app and go to Settings and then Linked Devices. You should see your camera preview open up.
In the terminal, run npm run link and you should soon see a giant QR code. Scan that with Signal.
If you get an error, restart the node process so that you can try with a different QR (it may have expired).
If you ever need to unlink it and cleanup the data and keys, run npm run clean.
Make sure to delete the linked device from the Signal mobile app as well.
configure
Copy config.sample.json to config.json and update it to match your setup.
register the app service
Generate an signal-registration.yaml file with node index.js -r -u "http://your-bridge-server:8090"
Note: The 'registration' setting in the config.json needs to set to the path of this file. By default, it already is.
Copy this signal-registration.yaml file to your home server, then edit it, setting its url to point to your bridge server. e.g. url: 'http://your-bridge-server.example.org:8090'
Edit your homeserver.yaml file and update the app_service_config_files with the path to the signal-registration.yaml file.
Restart your HS.
Launch the bridge with start.sh or node index.js. If you want to run the bridge as a service you can use the matrix-puppet-signal.service file as a template for every systemd based operating system.
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