feature(BackendRuntime): support lifecycle hook fields for BackendRuntime

api/inference/v1alpha1/backendruntime_types.go

@@ -88,6 +88,9 @@ type BackendRuntimeSpec struct {
 	// Envs represents the environments set to the container.
 	// +optional
 	Envs []corev1.EnvVar `json:"envs,omitempty"`
+	// Lifecycle represents hooks executed during the lifecycle of the container.
+	// +optional
+	Lifecycle *corev1.Lifecycle `json:"lifecycle,omitempty"`
 	// Periodic probe of backend liveness.
 	// Backend will be restarted if the probe fails.
 	// Cannot be updated.

pkg/controller/inference/playground_controller.go

@@ -313,6 +313,9 @@ func buildTemplate(models []*coreapi.OpenModel, playground *inferenceapi.Playgro
 	// commands
 	commands := parser.Commands()
 
+	// lifecycle
+	lifecycle := parser.Lifecycle()
+
 	// probe
 	var livenessProbe, readinessProbe, startupProbe *corev1.Probe
 	if backendRuntime.Spec.StartupProbe != nil {
@@ -337,6 +340,7 @@ func buildTemplate(models []*coreapi.OpenModel, playground *inferenceapi.Playgro
 					Command:   commands,
 					Args:      args,
 					Env:       envs,
+					Lifecycle: lifecycle,
 					Ports: []corev1.ContainerPort{
 						{
 							Name:          "http",

pkg/controller_helper/backendruntime/backendruntime.go

@@ -56,6 +56,10 @@ func (p *BackendRuntimeParser) Envs() []corev1.EnvVar {
 	return p.backendRuntime.Spec.Envs
 }
 
+func (p *BackendRuntimeParser) Lifecycle() *corev1.Lifecycle {
+	return p.backendRuntime.Spec.Lifecycle
+}
+
 func (p *BackendRuntimeParser) Args() ([]string, error) {
 	mainModel := p.models[0]
 

test/config/backends/fake_backend.yaml

@@ -13,6 +13,19 @@ spec:
     - echo "hello"
   image: busybox
   version: latest
+  lifecycle:
+    postStart:
+      exec:
+        command:
+          - /bin/sh
+          - -c
+          - echo "Container started."
+    preStop:
+      exec:
+        command:
+          - /bin/sh
+          - -c
+          - echo "Container stopped."
   recommendedConfigs:
     - name: default
       args:

test/integration/controller/inference/playground_test.go

@@ -455,5 +455,32 @@ var _ = ginkgo.Describe("playground controller test", func() {
 				},
 			},
 		}),
+		ginkgo.Entry("Playground with fake-backend", &testValidatingCase{
+			makePlayground: func() *inferenceapi.Playground {
+				return wrapper.MakePlayground("playground", ns.Name).ModelClaim(model.Name).Label(coreapi.ModelNameLabelKey, model.Name).
+					BackendRuntime("fake-backend").
+					Obj()
+			},
+			updates: []*update{
+				{
+					updateFunc: func(playground *inferenceapi.Playground) {
+						gomega.Expect(k8sClient.Create(ctx, playground)).To(gomega.Succeed())
+					},
+					checkFunc: func(ctx context.Context, k8sClient client.Client, playground *inferenceapi.Playground) {
+						validation.ValidatePlayground(ctx, k8sClient, playground)
+						validation.ValidatePlaygroundStatusEqualTo(ctx, k8sClient, playground, inferenceapi.PlaygroundProgressing, "Pending", metav1.ConditionTrue)
+					},
+				},
+				{
+					updateFunc: func(playground *inferenceapi.Playground) {
+						util.UpdateLwsToReady(ctx, k8sClient, playground.Name, playground.Namespace)
+					},
+					checkFunc: func(ctx context.Context, k8sClient client.Client, playground *inferenceapi.Playground) {
+						validation.ValidatePlayground(ctx, k8sClient, playground)
+						validation.ValidatePlaygroundStatusEqualTo(ctx, k8sClient, playground, inferenceapi.PlaygroundAvailable, "PlaygroundReady", metav1.ConditionTrue)
+					},
+				},
+			},
+		}),
 	)
 })

test/util/validation/validate_playground.go

@@ -164,6 +164,11 @@ func ValidatePlayground(ctx context.Context, k8sClient client.Client, playground
 			return errors.New("command not right")
 		}
 
+		// compare lifecycle
+		if diff := cmp.Diff(parser.Lifecycle(), service.Spec.WorkloadTemplate.WorkerTemplate.Spec.Containers[0].Lifecycle); diff != "" {
+			return errors.New("lifecycle not right")
+		}
+
 		// compare fields only can be configured in backend.
 
 		if backendRuntime.Spec.StartupProbe != nil {

test/util/wrapper/backend.go

@@ -62,6 +62,11 @@ func (w *BackendRuntimeWrapper) Command(commands []string) *BackendRuntimeWrappe
 	return w
 }
 
+func (w *BackendRuntimeWrapper) Lifecycle(lifecycle *corev1.Lifecycle) *BackendRuntimeWrapper {
+	w.Spec.Lifecycle = lifecycle
+	return w
+}
+
 func (w *BackendRuntimeWrapper) Arg(name string, args []string) *BackendRuntimeWrapper {
 	if w.Spec.RecommendedConfigs == nil {
 		w.Spec.RecommendedConfigs = []inferenceapi.RecommendedConfig{