dockershim: fix docker filter, Hostname, and the apiversion

pkg/kubelet/dockershim/docker_container.go

@@ -103,7 +103,6 @@ func (ds *dockerService) CreateContainer(podSandboxID string, config *runtimeApi
 		Name: makeContainerName(sandboxConfig, config),
 		Config: &dockercontainer.Config{
 			// TODO: set User.
-			Hostname:   sandboxConfig.GetHostname(),
 			Entrypoint: dockerstrslice.StrSlice(config.GetCommand()),
 			Cmd:        dockerstrslice.StrSlice(config.GetArgs()),
 			Env:        generateEnvList(config.GetEnvs()),

pkg/kubelet/dockershim/docker_service.go

@@ -80,10 +80,13 @@ func (ds *dockerService) Version(apiVersion string) (*runtimeApi.VersionResponse
 	}
 	runtimeAPIVersion := kubeAPIVersion
 	name := dockerRuntimeName
+	// Docker API version (e.g., 1.23) is not semver compatible. Add a ".0"
+	// suffix to remedy this.
+	apiVersion := fmt.Sprintf("%s.0", v.APIVersion)
 	return &runtimeApi.VersionResponse{
 		Version:           &runtimeAPIVersion,
 		RuntimeName:       &name,
 		RuntimeVersion:    &v.Version,
-		RuntimeApiVersion: &v.APIVersion,
+		RuntimeApiVersion: &apiVersion,
 	}, nil
 }

pkg/kubelet/dockershim/helpers.go

@@ -161,15 +161,15 @@ func getNetworkNamespace(c *dockertypes.ContainerJSON) string {
 // dockerFilter wraps around dockerfilters.Args and provides methods to modify
 // the filter easily.
 type dockerFilter struct {
-	f *dockerfilters.Args
+	args *dockerfilters.Args
 }
 
 func newDockerFilter(args *dockerfilters.Args) *dockerFilter {
-	return &dockerFilter{f: args}
+	return &dockerFilter{args: args}
 }
 
 func (f *dockerFilter) Add(key, value string) {
-	f.Add(key, value)
+	f.args.Add(key, value)
 }
 
 func (f *dockerFilter) AddLabel(key, value string) {