play kube: service container

Add the notion of a "service container" to play kube.  A service
container is started before the pods in play kube and is (reverse)
linked to them.  The service container is stopped/removed *after*
all pods it is associated with are stopped/removed.

In other words, a service container tracks the entire life cycle
of a service started via `podman play kube`.  This is required to
enable `play kube` in a systemd unit file.

The service container is only used when the `--service-container`
flag is set on the CLI.  This flag has been marked as hidden as it
is not meant to be used outside the context of `play kube`.  It is
further not supported on the remote client.

The wiring with systemd will be done in a later commit.

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

3 files changed, 68 insertions, 13 deletions

diff --git a/test/system/200-pod.bats b/test/system/200-pod.bats
index 39982848f..4250f2680 100644
--- a/test/system/200-pod.bats
+++ b/test/system/200-pod.bats
@@ -408,19 +408,6 @@ EOF
     run_podman pod rm test
 }
 
-# Wait for the pod (1st arg) to transition into the state (2nd arg)
-function _ensure_pod_state() {
-    for i in {0..5}; do
-        run_podman pod inspect $1 --format "{{.State}}"
-        if [[ $output == "$2" ]]; then
-            break
-        fi
-        sleep 0.5
-    done
-
-    is "$output" "$2" "unexpected pod state"
-}
-
 @test "pod exit policies" {
     # Test setting exit policies
     run_podman pod create
diff --git a/test/system/700-play.bats b/test/system/700-play.bats
index 7988b26a4..2e5327a85 100644
--- a/test/system/700-play.bats
+++ b/test/system/700-play.bats
@@ -100,6 +100,61 @@ RELABEL="system_u:object_r:container_file_t:s0"
     run_podman pod rm -t 0 -f test_pod
 }
 
+@test "podman play --service-container" {
+    skip_if_remote "service containers only work locally"
+
+    TESTDIR=$PODMAN_TMPDIR/testdir
+    mkdir -p $TESTDIR
+
+yaml="
+apiVersion: v1
+kind: Pod
+metadata:
+  labels:
+    app: test
+  name: test_pod
+spec:
+  containers:
+  - command:
+    - top
+    image: $IMAGE
+    name: test
+    resources: {}
+"
+
+    echo "$yaml" > $PODMAN_TMPDIR/test.yaml
+    run_podman play kube --service-container=true $PODMAN_TMPDIR/test.yaml
+
+    # Make sure that the service container exists and runs.
+    run_podman container inspect "352a88685060-service" --format "{{.State.Running}}"
+    is "$output" "true"
+
+    # Stop the *main* container and make sure that
+    #  1) The pod transitions to Exited
+    #  2) The service container is stopped
+    #  #) The service container is marked as an service container
+    run_podman stop test_pod-test
+    _ensure_pod_state test_pod Exited
+    run_podman container inspect "352a88685060-service" --format "{{.State.Running}}"
+    is "$output" "false"
+    run_podman container inspect "352a88685060-service" --format "{{.IsService}}"
+    is "$output" "true"
+
+    # Restart the pod, make sure the service is running again
+    run_podman pod restart test_pod
+    run_podman container inspect "352a88685060-service" --format "{{.State.Running}}"
+    is "$output" "true"
+
+    # Kill the pod and make sure the service is not running
+    run_podman pod kill test_pod
+    run_podman container inspect "352a88685060-service" --format "{{.State.Running}}"
+    is "$output" "false"
+
+    # Remove the pod and make sure the service is removed along with it
+    run_podman pod rm test_pod
+    run_podman 1 container exists "352a88685060-service"
+}
+
 @test "podman play --network" {
     TESTDIR=$PODMAN_TMPDIR/testdir
     mkdir -p $TESTDIR
diff --git a/test/system/helpers.bash b/test/system/helpers.bash
index 138d668f4..072131202 100644
--- a/test/system/helpers.bash
+++ b/test/system/helpers.bash
@@ -392,6 +392,19 @@ function pause_image() {
     echo "localhost/podman-pause:$output"
 }
 
+# Wait for the pod (1st arg) to transition into the state (2nd arg)
+function _ensure_pod_state() {
+    for i in {0..5}; do
+        run_podman pod inspect $1 --format "{{.State}}"
+        if [[ $output == "$2" ]]; then
+            break
+        fi
+        sleep 0.5
+    done
+
+    is "$output" "$2" "unexpected pod state"
+}
+
 ###########################
 #  _add_label_if_missing  #  make sure skip messages include rootless/remote
 ###########################