kube play: support auto updates and rollbacks

Add auto-update support to `podman kube play`.  Auto-update policies can
be configured for:
 * the entire pod via the `io.containers.autoupdate` annotation
 * a specific container via the `io.containers.autoupdate/$name` annotation

To make use of rollbacks, the `io.containers.sdnotify` policy should be
set to `container` such that the workload running _inside_ the container
can send the READY message via the NOTIFY_SOCKET once ready.  For
further details on auto updates and rollbacks, please refer to the
specific article [1].

Since auto updates and rollbacks bases on Podman's systemd integration,
the k8s YAML must be executed in the `podman-kube@` systemd template.
For further details on how to run k8s YAML in systemd via Podman, please
refer to the specific article [2].

An examplary k8s YAML may look as follows:
```YAML
apiVersion: v1
kind: Pod
metadata:
  annotations:
      io.containers.autoupdate: "local"
      io.containers.autoupdate/b: "registry"
  labels:
    app: test
  name: test_pod
spec:
  containers:
  - command:
    - top
    image: alpine
    name: a
  - command:
    - top
    image: alpine
    name: b
```

[1] https://www.redhat.com/sysadmin/podman-auto-updates-rollbacks
[2] https://www.redhat.com/sysadmin/kubernetes-workloads-podman-systemd

Signed-off-by: Valentin Rothberg <vrothberg@redhat.com>

1 files changed, 14 insertions, 0 deletions

diff --git a/test/system/helpers.systemd.bash b/test/system/helpers.systemd.bash
index d9abc087d..afbab6e08 100644
--- a/test/system/helpers.systemd.bash
+++ b/test/system/helpers.systemd.bash
@@ -32,3 +32,17 @@ journalctl() {
 systemd-run() {
     command systemd-run $_DASHUSER "$@";
 }
+
+install_kube_template() {
+    # If running from a podman source directory, build and use the source
+    # version of the play-kube-@ unit file
+    unit_name="podman-kube@.service"
+    unit_file="contrib/systemd/system/${unit_name}"
+    if [[ -e ${unit_file}.in ]]; then
+        echo "# [Building & using $unit_name from source]" >&3
+        # Force regenerating unit file (existing one may have /usr/bin path)
+        rm -f $unit_file
+        BINDIR=$(dirname $PODMAN) make $unit_file
+        cp $unit_file $UNIT_DIR/$unit_name
+    fi
+}