Feature request: Import Signal desktop database

[nettnikl]

Hi!

What

I would like to ask for the possibility to import a Signal Desktop database/backup back into the android app. If possible, but not necessarily merging with the existing content.

Use cases

• Losing your phone
• You relied on existing backup solution that work for all apps but Signal (Titanium Backup, NeoBackup, the Google backup solution, etc., see this issue)

But

• You have a desktop computer (which usually cannot be pickpocket-ed as easily)

Reasoning

There is a great need for seamless, pain-free import from Signal Desktop to Signal Android. This was most prominently asked for here: signalapp/Signal-Desktop#522 but it naturally has been tackled by other projects and asked for elsewhere.

https://community.signalusers.org/t/backup-restore-from-desktop-to-android/29456
https://community.signalusers.org/t/importing-messages-from-desktop-to-mobile/1688/12
signalapp/Signal-Desktop#4264
signalapp#12144
xeals/signal-back#78
xeals/signal-back#14

As you can see, also the non official projects with this reasoning are very popular.

https://github.com/tbvdm/sigtop
https://github.com/carderne/signal-export

In addition, other projects seem to consider this project here to be the most advanced in what it does.

mollyim/mollyim-android#71

Also, i see the official Signal team in quite a few cases ignoring requests by popular demand, as can be seen here.

signalapp#10618
signalapp@3134837

All in all, i have a strong feeling, this is the correct project to ask for this feature for. (Sorry for the long text + many links, but x-pinging helps to find all threads i found during my research.)

Issues and Problems

I've read that the db scheme is not only in general different (eg. where are media files stored https://community.signalusers.org/t/backup-restore-from-desktop-to-android/29456), but also changes from time to time. So, this feature may break - however

[johanw666]

So, this feature may break

Yes, so it requires maintenance. Probably a lot of it. I already included someone else's WA import code in my fork, and adding an extra import could go in the same screen, but doing more than just import messages (which can be done already by putting them in an xml file and using plaintext import) will be a massive job: Signal desktop does not encrypt media so I'd have to write code for that to import it in the database too, it takes contacts from a coupled device so I don't know if there even is a 1:1 mapping possible here.

All in all it is a job that is larger than I have available time now.

[nettnikl]

Could you elaborate further?

What kind of encryption would be needed?

In the code i see some messages being stored as "sms", others as "mms", is this just internal Signal lingo for media messages and text messages?

What data do you need for each entry? Recipient, Text, Timestamp,... ?