Update init ctr default for play kube

Update the init container type default to once instead
of always to match k8s behavior.
Add a new annotation that can be used to change the init
ctr type in the kube yaml.

Signed-off-by: Urvashi Mohnani <umohnani@redhat.com>

docs/source/markdown/podman-play-kube.1.md

@@ -22,7 +22,7 @@ Currently, the supported Kubernetes kinds are:
 
 Only two volume types are supported by play kube, the *hostPath* and *persistentVolumeClaim* volume types. For the *hostPath* volume type, only the  *default (empty)*, *DirectoryOrCreate*, *Directory*, *FileOrCreate*, *File*, *Socket*, *CharDevice* and *BlockDevice* subtypes are supported. Podman interprets the value of *hostPath* *path* as a file path when it contains at least one forward slash, otherwise Podman treats the value as the name of a named volume. When using a *persistentVolumeClaim*, the value for *claimName* is the name for the Podman named volume.
 
-Note: When playing a kube YAML with init containers, the init container will be created with init type value `always`.
+Note: When playing a kube YAML with init containers, the init container will be created with init type value `once`. To change the default type, use the `io.podman.annotations.init.container.type` annotation to set the type to `always`.
 
 Note: *hostPath* volume types created by play kube will be given an SELinux shared label (z), bind mounts are not relabeled (use `chcon -t container_file_t -R <directory>`).
 

libpod/define/annotations.go

@@ -135,6 +135,11 @@ const (
 	// creating a checkpoint image to specify the name of host distribution on
 	// which the checkpoint was created.
 	CheckpointAnnotationDistributionName = "io.podman.annotations.checkpoint.distribution.name"
+
+	// InitContainerType is used by play kube when playing a kube yaml to specify the type
+	// of the init container.
+	InitContainerType = "io.podman.annotations.init.container.type"
+
 	// MaxKubeAnnotation is the max length of annotations allowed by Kubernetes.
 	MaxKubeAnnotation = 63
 )

pkg/domain/infra/abi/play.go

@@ -507,13 +507,17 @@ func (ic *ContainerEngine) playKubePod(ctx context.Context, podName string, podY
 		for k, v := range podSpec.PodSpecGen.Labels { // add podYAML labels
 			labels[k] = v
 		}
+		initCtrType := annotations[define.InitContainerType]
+		if initCtrType == "" {
+			initCtrType = define.OneShotInitContainer
+		}
 
 		specgenOpts := kube.CtrSpecGenOptions{
 			Annotations:        annotations,
 			ConfigMaps:         configMaps,
 			Container:          initCtr,
 			Image:              pulledImage,
-			InitContainerType:  define.AlwaysInitContainer,
+			InitContainerType:  initCtrType,
 			Labels:             labels,
 			LogDriver:          options.LogDriver,
 			LogOptions:         options.LogOptions,

test/e2e/play_kube_test.go

@@ -1559,8 +1559,10 @@ var _ = Describe("Podman play kube", func() {
 	})
 
 	// If you have an init container in the pod yaml, podman should create and run the init container with play kube
-	It("podman play kube test with init containers", func() {
-		pod := getPod(withPodInitCtr(getCtr(withImage(ALPINE), withCmd([]string{"echo", "hello"}), withInitCtr(), withName("init-test"))), withCtr(getCtr(withImage(ALPINE), withCmd([]string{"top"}))))
+	// With annotation set to always
+	It("podman play kube test with init containers and annotation set", func() {
+		// With the init container type annotation set to always
+		pod := getPod(withAnnotation("io.podman.annotations.init.container.type", "always"), withPodInitCtr(getCtr(withImage(ALPINE), withCmd([]string{"echo", "hello"}), withInitCtr(), withName("init-test"))), withCtr(getCtr(withImage(ALPINE), withCmd([]string{"top"}))))
 		err := generateKubeYaml("pod", pod, kubeYaml)
 		Expect(err).To(BeNil())
 
@@ -1585,6 +1587,29 @@ var _ = Describe("Podman play kube", func() {
 		Expect(inspect.OutputToString()).To(ContainSubstring("running"))
 	})
 
+	// If you have an init container in the pod yaml, podman should create and run the init container with play kube
+	// Using default init container type (once)
+	It("podman play kube test with init container type set to default value", func() {
+		// Using the default init container type (once)
+		pod := getPod(withPodInitCtr(getCtr(withImage(ALPINE), withCmd([]string{"echo", "hello"}), withInitCtr(), withName("init-test"))), withCtr(getCtr(withImage(ALPINE), withCmd([]string{"top"}))))
+		err := generateKubeYaml("pod", pod, kubeYaml)
+		Expect(err).To(BeNil())
+
+		kube := podmanTest.Podman([]string{"play", "kube", kubeYaml})
+		kube.WaitWithDefaultTimeout()
+		Expect(kube).Should(Exit(0))
+
+		// Expect the number of containers created to be 2, infra and regular container
+		numOfCtrs := podmanTest.NumberOfContainers()
+		Expect(numOfCtrs).To(Equal(2))
+
+		// Regular container should be in running state
+		inspect := podmanTest.Podman([]string{"inspect", "--format", "{{.State.Status}}", "testPod-" + defaultCtrName})
+		inspect.WaitWithDefaultTimeout()
+		Expect(inspect).Should(Exit(0))
+		Expect(inspect.OutputToString()).To(ContainSubstring("running"))
+	})
+
 	// If you supply only args for a Container, the default Entrypoint defined in the Docker image is run with the args that you supplied.
 	It("podman play kube test correct command with only set args in yaml file", func() {
 		pod := getPod(withCtr(getCtr(withImage(REGISTRY_IMAGE), withCmd(nil), withArg([]string{"echo", "hello"}))))