The rather raw and scarce output of `podman auto-update` has been a
thorn in my eyes for a longer while. So far, Podman would only print
updated systemd units, one per line, without further formatting.
Motivated by issue #9949 which is asking for some more useful
information in combination with a dry-run feature, I sat down and
reflected which information may come in handy.
Running `podman auto-update` will now look as follows:
```
$ podman auto-update
Trying to pull [...]
UNIT CONTAINER IMAGE POLICY UPDATED
container-test.service 08fd34e533fd (test) localhost:5000/busybox registry false
```
Also refactor the spaghetti code in the backend a bit to make it easier
to digest and maintain.
For easier testing and for the sake of consistency with other commands
listing output, add a `--format` flag.
The man page will get an overhaul in a follow up commit.
Signed-off-by: Valentin Rothberg <rothberg@redhat.com>
01cfb51fe9