Add the ContainerRuntime interface stub for rkt app level API

pkg/kubelet/rktshim/app-interface.go

+/*
+Copyright 2016 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package rktshim
+
+import (
+	"io"
+
+	kubeletApi "k8s.io/kubernetes/pkg/kubelet/api"
+	runtimeApi "k8s.io/kubernetes/pkg/kubelet/api/v1alpha1/runtime"
+)
+
+// Runtime provides an API for lifecycle, inspection and introspection
+// operations in a blocking manner using the App level API provided by rkt.
+type Runtime struct{}
+
+// TODO(tmrts): Fill out the creation configuration fields.
+type RuntimeConfig struct{}
+
+// NewRuntime creates a container.Runtime instance using the Runtime.
+func NewRuntime(RuntimeConfig) (kubeletApi.ContainerManager, error) {
+	return &Runtime{}, nil
+}
+
+// CreateContainer creates an app inside the provided pod sandbox and returns the RawContainerID.
+func (*Runtime) CreateContainer(string, *runtimeApi.ContainerConfig, *runtimeApi.PodSandboxConfig) (string, error) {
+	panic("not implemented")
+}
+
+// StartContainer starts a created app.
+func (*Runtime) StartContainer(string) error {
+	panic("not implemented")
+}
+
+// StopContainer stops a running app with a grace period (i.e. timeout).
+func (*Runtime) StopContainer(string, int64) error {
+	panic("not implemented")
+}
+
+// RemoveContainer removes the app from a pod sandbox.
+func (*Runtime) RemoveContainer(string) error {
+	panic("not implemented")
+}
+
+// ListContainers lists out the apps residing inside the pod sandbox using the ContainerFilter.
+func (*Runtime) ListContainers(*runtimeApi.ContainerFilter) ([]*runtimeApi.Container, error) {
+	panic("not implemented")
+}
+
+// ContainerStatus returns the RawContainerStatus of an app inside the pod sandbox.
+func (*Runtime) ContainerStatus(string) (*runtimeApi.ContainerStatus, error) {
+	panic("not implemented")
+}
+
+// Exec executes a command inside an app running inside a pod sanbox.
+func (*Runtime) Exec(string, []string, bool, io.Reader, io.WriteCloser, io.WriteCloser) error {
+	panic("not implemented")
+}