This project makes use of signal-cli to create a service which automatically archives any media received through Signal groups or which are sent directly to the bot. This can come in handy if e.g. your family shares things in a Signal group and you don’t want to download everything by hand to archive it, or if you have certain media files you want to keep permanently which you can simply forward to the bot.
As a prerequisite, you need a spare phone number – either mobile or landline. You need to set up signal-cli to be running in DBus daemon mode (configured with your number), then the script available here can access Signal and listen to anything you direct at the configured number. For details on the setup please see the project’s README file.
The use case I have this for is mainly to add the configured number to any (bigger) Signal group chat. I have the bot script running on my home server – this way any media which are shared in the groups automatically are saved to my local NAS, complete with source (group/individual), timestamp and accompanying message.