auto-update: make output more user friendly

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>

1 files changed, 10 insertions, 5 deletions

diff --git a/test/system/255-auto-update.bats b/test/system/255-auto-update.bats
index cce8973fc..4959bb6aa 100644
--- a/test/system/255-auto-update.bats
+++ b/test/system/255-auto-update.bats
@@ -121,10 +121,10 @@ function _confirm_update() {
     generate_service alpine image
 
     _wait_service_ready container-$cname.service
-    run_podman auto-update
+    run_podman auto-update --format "{{.Unit}},{{.Image}},{{.Updated}},{{.Policy}}"
     is "$output" "Trying to pull.*" "Image is updated."
-    is "$output" ".*Restarted the following systemd units:
-container-$cname.service" "Systemd unit has been restarted"
+    is "$output" ".*container-$cname.service,quay.io/libpod/alpine:latest,true,registry.*" "Image is updated."
+
     _confirm_update $cname $ori_image
 }
 
@@ -153,10 +153,15 @@ container-$cname.service" "Systemd unit has been restarted"
 
 @test "podman auto-update - label io.containers.autoupdate=local" {
     generate_service localtest local
-    podman commit --change CMD=/bin/bash $cname quay.io/libpod/localtest:latest
+    image=quay.io/libpod/localtest:latest
+    podman commit --change CMD=/bin/bash $cname $image
+    podman image inspect --format "{{.ID}}" $image
+    imageID="$output"
 
     _wait_service_ready container-$cname.service
-    run_podman auto-update
+    run_podman auto-update --format "{{.Unit}},{{.Image}},{{.Updated}},{{.Policy}}"
+    is "$output" ".*container-$cname.service,quay.io/libpod/localtest:latest,true,local.*" "Image is updated."
+
     _confirm_update $cname $ori_image
 }