Can't backup via adb - possible AndroidManifest.xml misconfiguration?

[Trosan]

Hi folks,

first of all I am new to Android development, so please excuse if the following suggestion is dumb.

I noticed that this app can’t be backed-up via “adb backup” although android:allowBackup is set to “true” in the AndroidManifest.xml. The resulting file simply contains nothing reasonable.

I have the following idea for what might cause the issue, maybe you can tell me if that makes sense:
In the AndroidManifest.xml (see https://gitlab.com/bitfireAT/davx5-ose/blob/master-ose/app/src/main/AndroidManifest.xml#L42), there is the line

android:fullBackupContent=“false”.

This page https://developer.android.com/guide/topics/manifest/application-element however, says that “android:fullBackupContent” needs to be a string instead of a boolean:

This attribute points to an XML file that contains full backup rules for Auto Backup. These rules determine what files get backed up. For more information, see XML Config Syntax for Auto Backup.

This attribute is optional. If it is not specified, by default, Auto Backup includes most of your app’s files. For more information, see Files that are backed up. "

I thought this might be the cause for the issue. Does anyone know the reason for the value set to “false” in that file?

[rfc2822]

@Trosan said in Can't backup via adb - possible AndroidManifest.xml misconfiguration?:

I thought this might be the cause for the issue. Does anyone know the reason for the value set to “false” in that file?

It should be android:fullBackupOnly="false" (because Auto Backup won’t work with DAVx⁵ accounts) and android:allowBackup="false" (because there’s no BackupAgent for DAVx⁵ accounts).

[rfc2822]

Strange… Android Studio shows these docs:

which is probably the source of confusion. Now the question is, where does it take this info from and which information is correct? From the name, fullBackupOnly sounds better fitting than fullBackupContent.

[Trosan]

So, from what I understood, DAVx5 does not support backup at all!? Okay, this somehow answers my question. Is there a technical reason for that or is it just not yet implemented?

(Maybe that explains why copying the data/data/at.bitfire.davdroid folder didn’t let me use my settings on my new phone…)

[rfc2822]

@Trosan said in Can't backup via adb - possible AndroidManifest.xml misconfiguration?:

So, from what I understood, DAVx5 does not support backup at all!? Okay, this somehow answers my question. Is there a technical reason for that or is it just not yet implemented?

Both. Most other apps don’t need accounts and thus can automatically be backed up using Android’s Auto Backup. However, this method is not applicable to DAVx⁵, where backup would require much more efforts. https://gitlab.com/bitfireAT/davx5-ose/wikis/Roadmap

[Trosan]

Thank you for your fast response! So the allowBackup setting was a bug, which I saw you already fixed. Thank you!