Comment 3 for bug 1515463

Well, the string returned by ubuntu-cloudimg-query already requires mangling to be usable with the lxc-ubuntu-cloud template (as we do inside the ubuntu-cloud template).

As there are no full cloud images compressed using .tar.xz, ubuntu-cloudimg-query will continue to return .tar.gz and it's up to whatever piece of software currently mangles its return value to the .root.tar.gz equivalent to instead mangle it to .root.tar.xz (as I did in the ubuntu-cloud template).

Anyway, as I said, I'll be changing the tar commands so they don't care about the compression algorithm, that should make transitioning much easier.