Properly Removing Corrupted or Unwanted Versions from the Repository

[its-monotype]

I would like to know the correct steps for removing corrupted or unwanted versions from the repository. Here's what I assume should be done:

1. Modify targets.json metadata:

   • Remove the entries related to the specific version from the signed.targets object. This includes removing the .tar.gz and .patch references that correspond to the version we want to remove.

2. Remove files from the repository:

   • Delete the actual .tar.gz and .patch files from the repository's targets directory.

Could someone please confirm if my understanding is correct? Are there any additional steps or precautions I should be aware of when performing this task?

[dennisvang]

@its-monotype Good question.

In addition to the steps described above, you'll also need to re-sign the affected metadata files.

Note that tufup provides a shortcut for the removal of the latest target. This removes the target files and updates the metadata files accordingly, including re-signing.

From the command line:

tufup targets remove-latest <path-to-keystore>

Also see CLI help: tufup targets -h

The remove-latest CLI implementation can be used as an example for scripting. As you can see here, it uses Repository.remove_latest_bundle() followed by Repository.publish_changes().

If you want to remove a specific version that is not the latest, you can use Repository.remove_latest_bundle() as an example.

Alternatively, you could remove the metadata entries manually, then re-sign.

[RasmusN]

Almost the same question:
Is it safe to delete old versions from the targets directory in the remote repository?

If so, can I just delete them or do I need to update some metadata files?

[dennisvang]

Is it safe to delete old versions from the targets directory in the remote repository?

@RasmusN Good question.

Removing old versions, i.e. versions other than the latest version, is only safe if you use full updates.

Presently, tufup does not check if the current (running) version of your app is available in the targets list, so full updates from any old version to the latest one should still work.

However, removing old versions is not safe if you use patch updates, because these depend upon each other. Removing a patch, other than the latest one, will break (part of) the chain. Currently, there is no safeguard against this. That's why the current implementation only has a built-in command for rolling back the latest version (remove-latest).

Beware that patch updates are enabled by default, but you can disable them using the patch argument:

check_for_updates(patch=False)

If so, can I just delete them or do I need to update some metadata files?

In principle, you can remove any version, as long as the change is reflected in the metadata. Have a look at the remove-latest command, as described above, to see what this entails.

Basically, if you remove and/or modify any file from the targets directory, the targets.json file must be updated to reflect the new state of that directory. If targets.json is updated, then snapshot.json and timestamp.json must also be updated. If you update targets metadata using the built-in methods, snapshot and timestamp metadata will be updated automatically.