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Code Issues Projects Releases Wiki Activity

move runtime details into ContainerRuntime

Browse Source 
Created ContainerRuntime and used it in preflight checks,
'reset' and 'image' modules.
This commit is contained in:
Ed Bartosh 2018-05-31 17:25:40 +03:00
parent 4239729fc1
commit bfb08bbb7b
14 changed files with 364 additions and 628 deletions
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2
cmd/kubeadm/app/cmd/BUILD
View File

@ -54,6 +54,7 @@ go_library(
"//cmd/kubeadm/app/util/config:go_default_library",
"//cmd/kubeadm/app/util/dryrun:go_default_library",
"//cmd/kubeadm/app/util/kubeconfig:go_default_library",
"//cmd/kubeadm/app/util/runtime:go_default_library",
"//pkg/util/initsystem:go_default_library",
"//pkg/version:go_default_library",
"//staging/src/k8s.io/apimachinery/pkg/apis/meta/v1:go_default_library",
@ -96,6 +97,7 @@ go_test(
"//cmd/kubeadm/app/features:go_default_library",
"//cmd/kubeadm/app/preflight:go_default_library",
"//cmd/kubeadm/app/util/config:go_default_library",
"//cmd/kubeadm/app/util/runtime:go_default_library",
"//staging/src/k8s.io/api/core/v1:go_default_library",
"//staging/src/k8s.io/apimachinery/pkg/api/errors:go_default_library",
"//staging/src/k8s.io/apimachinery/pkg/apis/meta/v1:go_default_library",

17
cmd/kubeadm/app/cmd/config.go
View File

@ -43,6 +43,7 @@ import (
kubeadmutil "k8s.io/kubernetes/cmd/kubeadm/app/util"
configutil "k8s.io/kubernetes/cmd/kubeadm/app/util/config"
kubeconfigutil "k8s.io/kubernetes/cmd/kubeadm/app/util/kubeconfig"
utilruntime "k8s.io/kubernetes/cmd/kubeadm/app/util/runtime"
utilsexec "k8s.io/utils/exec"
)
@ -407,9 +408,9 @@ func NewCmdConfigImagesPull() *cobra.Command {
kubeadmutil.CheckErr(err)
internalcfg, err := configutil.ConfigFileAndDefaultsToInternalConfig(cfgPath, cfg)
kubeadmutil.CheckErr(err)
puller, err := images.NewCRInterfacer(utilsexec.New(), internalcfg.GetCRISocket())
containerRuntime, err := utilruntime.NewContainerRuntime(utilsexec.New(), internalcfg.GetCRISocket())
kubeadmutil.CheckErr(err)
imagesPull := NewImagesPull(puller, images.GetAllImages(internalcfg))
imagesPull := NewImagesPull(containerRuntime, images.GetAllImages(internalcfg))
kubeadmutil.CheckErr(imagesPull.PullAll())
},
}
@ -421,22 +422,22 @@ func NewCmdConfigImagesPull() *cobra.Command {
// ImagesPull is the struct used to hold information relating to image pulling
type ImagesPull struct {
puller images.Puller
images []string
runtime utilruntime.ContainerRuntime
images []string
}
// NewImagesPull initializes and returns the `kubeadm config images pull` command
func NewImagesPull(puller images.Puller, images []string) *ImagesPull {
func NewImagesPull(runtime utilruntime.ContainerRuntime, images []string) *ImagesPull {
return &ImagesPull{
puller: puller,
images: images,
runtime: runtime,
images: images,
}
}
// PullAll pulls all images that the ImagesPull knows about
func (ip *ImagesPull) PullAll() error {
for _, image := range ip.images {
if err := ip.puller.Pull(image); err != nil {
if err := ip.runtime.PullImage(image); err != nil {
return fmt.Errorf("failed to pull image %q: %v", image, err)
}
fmt.Printf("[config/images] Pulled %s\n", image)

49
cmd/kubeadm/app/cmd/config_test.go
View File

@ -30,6 +30,9 @@ import (
"k8s.io/kubernetes/cmd/kubeadm/app/cmd"
"k8s.io/kubernetes/cmd/kubeadm/app/features"
"k8s.io/kubernetes/cmd/kubeadm/app/util/config"
utilruntime "k8s.io/kubernetes/cmd/kubeadm/app/util/runtime"
"k8s.io/utils/exec"
fakeexec "k8s.io/utils/exec/testing"
)
const (
@ -181,27 +184,43 @@ func TestConfigImagesListRunWithoutPath(t *testing.T) {
}
}
type fakePuller struct {
count map[string]int
}
func (f *fakePuller) Pull(image string) error {
f.count[image]++
return nil
}
func TestImagesPull(t *testing.T) {
puller := &fakePuller{
count: make(map[string]int),
fcmd := fakeexec.FakeCmd{
RunScript: []fakeexec.FakeRunAction{
func() ([]byte, []byte, error) { return nil, nil, nil },
func() ([]byte, []byte, error) { return nil, nil, nil },
func() ([]byte, []byte, error) { return nil, nil, nil },
func() ([]byte, []byte, error) { return nil, nil, nil },
func() ([]byte, []byte, error) { return nil, nil, nil },
},
}
fexec := fakeexec.FakeExec{
CommandScript: []fakeexec.FakeCommandAction{
func(cmd string, args ...string) exec.Cmd { return fakeexec.InitFakeCmd(&fcmd, cmd, args...) },
func(cmd string, args ...string) exec.Cmd { return fakeexec.InitFakeCmd(&fcmd, cmd, args...) },
func(cmd string, args ...string) exec.Cmd { return fakeexec.InitFakeCmd(&fcmd, cmd, args...) },
func(cmd string, args ...string) exec.Cmd { return fakeexec.InitFakeCmd(&fcmd, cmd, args...) },
func(cmd string, args ...string) exec.Cmd { return fakeexec.InitFakeCmd(&fcmd, cmd, args...) },
},
LookPathFunc: func(cmd string) (string, error) { return "/usr/bin/docker", nil },
}
containerRuntime, err := utilruntime.NewContainerRuntime(&fexec, kubeadmapiv1alpha3.DefaultCRISocket)
if err != nil {
t.Errorf("unexpected NewContainerRuntime error: %v", err)
}
images := []string{"a", "b", "c", "d", "a"}
ip := cmd.NewImagesPull(puller, images)
err := ip.PullAll()
ip := cmd.NewImagesPull(containerRuntime, images)
err = ip.PullAll()
if err != nil {
t.Fatalf("expected nil but found %v", err)
}
if puller.count["a"] != 2 {
t.Fatalf("expected 2 but found %v", puller.count["a"])
if fcmd.RunCalls != len(images) {
t.Errorf("expected %d docker calls, got %d", len(images), fcmd.RunCalls)
}
}

75
cmd/kubeadm/app/cmd/reset.go
View File

@ -35,6 +35,7 @@ import (
kubeadmconstants "k8s.io/kubernetes/cmd/kubeadm/app/constants"
"k8s.io/kubernetes/cmd/kubeadm/app/preflight"
kubeadmutil "k8s.io/kubernetes/cmd/kubeadm/app/util"
utilruntime "k8s.io/kubernetes/cmd/kubeadm/app/util/runtime"
"k8s.io/kubernetes/pkg/util/initsystem"
utilsexec "k8s.io/utils/exec"
)
@ -147,12 +148,10 @@ func (r *Reset) Run(out io.Writer) error {
glog.Errorf("[reset] failed to unmount mounted directories in /var/lib/kubelet: %s\n", string(umountOutputBytes))
}
fmt.Println("[reset] removing kubernetes-managed containers")
dockerCheck := preflight.ServiceCheck{Service: "docker", CheckIfActive: true}
execer := utilsexec.New()
reset(execer, dockerCheck, r.criSocketPath)
glog.V(1).Info("[reset] removing kubernetes-managed containers")
if err := removeContainers(utilsexec.New(), r.criSocketPath); err != nil {
glog.Errorf("[reset] failed to remove containers: %+v", err)
}
dirsToClean := []string{"/var/lib/kubelet", "/etc/cni/net.d", "/var/lib/dockershim", "/var/run/kubernetes"}
// Only clear etcd data when the etcd manifest is found. In case it is not found, we must assume that the user
@ -184,63 +183,19 @@ func (r *Reset) Run(out io.Writer) error {
return nil
}
func reset(execer utilsexec.Interface, dockerCheck preflight.Checker, criSocketPath string) {
crictlPath, err := execer.LookPath("crictl")
if err == nil {
resetWithCrictl(execer, dockerCheck, criSocketPath, crictlPath)
} else {
resetWithDocker(execer, dockerCheck)
func removeContainers(execer utilsexec.Interface, criSocketPath string) error {
containerRuntime, err := utilruntime.NewContainerRuntime(execer, criSocketPath)
if err != nil {
return err
}
}
func resetWithDocker(execer utilsexec.Interface, dockerCheck preflight.Checker) {
if _, errors := dockerCheck.Check(); len(errors) == 0 {
if err := execer.Command("sh", "-c", "docker ps -a --filter name=k8s_ -q | xargs -r docker rm --force --volumes").Run(); err != nil {
glog.Errorln("[reset] failed to stop the running containers")
}
} else {
fmt.Println("[reset] docker doesn't seem to be running. Skipping the removal of running Kubernetes containers")
containers, err := containerRuntime.ListKubeContainers()
if err != nil {
return err
}
}
func resetWithCrictl(execer utilsexec.Interface, dockerCheck preflight.Checker, criSocketPath, crictlPath string) {
if criSocketPath != "" {
fmt.Printf("[reset] cleaning up running containers using crictl with socket %s\n", criSocketPath)
glog.V(1).Infoln("[reset] listing running pods using crictl")
params := []string{"-r", criSocketPath, "pods", "--quiet"}
glog.V(1).Infof("[reset] Executing command %s %s", crictlPath, strings.Join(params, " "))
output, err := execer.Command(crictlPath, params...).CombinedOutput()
if err != nil {
fmt.Printf("[reset] failed to list running pods using crictl: %v. Trying to use docker instead", err)
resetWithDocker(execer, dockerCheck)
return
}
sandboxes := strings.Fields(string(output))
glog.V(1).Infoln("[reset] Stopping and removing running containers using crictl")
for _, s := range sandboxes {
if strings.TrimSpace(s) == "" {
continue
}
params = []string{"-r", criSocketPath, "stopp", s}
glog.V(1).Infof("[reset] Executing command %s %s", crictlPath, strings.Join(params, " "))
if err := execer.Command(crictlPath, params...).Run(); err != nil {
fmt.Printf("[reset] failed to stop the running containers using crictl: %v. Trying to use docker instead", err)
resetWithDocker(execer, dockerCheck)
return
}
params = []string{"-r", criSocketPath, "rmp", s}
glog.V(1).Infof("[reset] Executing command %s %s", crictlPath, strings.Join(params, " "))
if err := execer.Command(crictlPath, params...).Run(); err != nil {
fmt.Printf("[reset] failed to remove the running containers using crictl: %v. Trying to use docker instead", err)
resetWithDocker(execer, dockerCheck)
return
}
}
} else {
fmt.Println("[reset] CRI socket path not provided for crictl. Trying to use docker instead")
resetWithDocker(execer, dockerCheck)
if err := containerRuntime.RemoveContainers(containers); err != nil {
return err
}
return nil
}
// cleanDir removes everything in a directory, but not the directory itself

125
cmd/kubeadm/app/cmd/reset_test.go
View File

@ -17,12 +17,10 @@ limitations under the License.
package cmd
import (
"errors"
"io"
"io/ioutil"
"os"
"path/filepath"
"strings"
"testing"
kubeadmapiv1alpha3 "k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm/v1alpha3"
@ -247,112 +245,13 @@ func newFakeDockerChecker(warnings, errors []error) preflight.Checker {
return &fakeDockerChecker{warnings: warnings, errors: errors}
}
func TestResetWithDocker(t *testing.T) {
fcmd := fakeexec.FakeCmd{
RunScript: []fakeexec.FakeRunAction{
func() ([]byte, []byte, error) { return nil, nil, nil },
func() ([]byte, []byte, error) { return nil, nil, errors.New("docker error") },
func() ([]byte, []byte, error) { return nil, nil, nil },
},
}
fexec := fakeexec.FakeExec{
CommandScript: []fakeexec.FakeCommandAction{
func(cmd string, args ...string) exec.Cmd { return fakeexec.InitFakeCmd(&fcmd, cmd, args...) },
func(cmd string, args ...string) exec.Cmd { return fakeexec.InitFakeCmd(&fcmd, cmd, args...) },
func(cmd string, args ...string) exec.Cmd { return fakeexec.InitFakeCmd(&fcmd, cmd, args...) },
},
}
resetWithDocker(&fexec, newFakeDockerChecker(nil, nil))
if fcmd.RunCalls != 1 {
t.Errorf("expected 1 call to Run, got %d", fcmd.RunCalls)
}
resetWithDocker(&fexec, newFakeDockerChecker(nil, nil))
if fcmd.RunCalls != 2 {
t.Errorf("expected 2 calls to Run, got %d", fcmd.RunCalls)
}
resetWithDocker(&fexec, newFakeDockerChecker(nil, []error{errors.New("test error")}))
if fcmd.RunCalls != 2 {
t.Errorf("expected 2 calls to Run, got %d", fcmd.RunCalls)
}
}
func TestResetWithCrictl(t *testing.T) {
func TestRemoveContainers(t *testing.T) {
fcmd := fakeexec.FakeCmd{
CombinedOutputScript: []fakeexec.FakeCombinedOutputAction{
// 2: socket path provided, not running with crictl (1x CombinedOutput, 2x Run)
func() ([]byte, error) { return []byte("1"), nil },
// 3: socket path provided, crictl fails, reset with docker (1x CombinedOuput fail, 1x Run)
func() ([]byte, error) { return nil, errors.New("crictl list err") },
func() ([]byte, error) { return []byte("id1\nid2"), nil },
},
RunScript: []fakeexec.FakeRunAction{
// 1: socket path not provided, running with docker
func() ([]byte, []byte, error) { return nil, nil, nil },
// 2: socket path provided, now running with crictl (1x CombinedOutput, 2x Run)
func() ([]byte, []byte, error) { return nil, nil, nil },
func() ([]byte, []byte, error) { return nil, nil, nil },
// 3: socket path provided, crictl fails, reset with docker (1x CombinedOuput, 1x Run)
func() ([]byte, []byte, error) { return nil, nil, nil },
// 4: running with no socket and docker fails (1x Run)
func() ([]byte, []byte, error) { return nil, nil, nil },
},
}
fexec := fakeexec.FakeExec{
CommandScript: []fakeexec.FakeCommandAction{
func(cmd string, args ...string) exec.Cmd { return fakeexec.InitFakeCmd(&fcmd, cmd, args...) },
func(cmd string, args ...string) exec.Cmd { return fakeexec.InitFakeCmd(&fcmd, cmd, args...) },
func(cmd string, args ...string) exec.Cmd { return fakeexec.InitFakeCmd(&fcmd, cmd, args...) },
func(cmd string, args ...string) exec.Cmd { return fakeexec.InitFakeCmd(&fcmd, cmd, args...) },
func(cmd string, args ...string) exec.Cmd { return fakeexec.InitFakeCmd(&fcmd, cmd, args...) },
func(cmd string, args ...string) exec.Cmd { return fakeexec.InitFakeCmd(&fcmd, cmd, args...) },
func(cmd string, args ...string) exec.Cmd { return fakeexec.InitFakeCmd(&fcmd, cmd, args...) },
},
}
// 1: socket path not provided, running with docker
resetWithCrictl(&fexec, newFakeDockerChecker(nil, nil), "", "crictl")
if fcmd.RunCalls != 1 {
t.Errorf("expected 1 call to Run, got %d", fcmd.RunCalls)
}
if !strings.Contains(fcmd.RunLog[0][2], "docker") {
t.Errorf("expected a call to docker, got %v", fcmd.RunLog[0])
}
// 2: socket path provided, now running with crictl (1x CombinedOutput, 2x Run)
resetWithCrictl(&fexec, newFakeDockerChecker(nil, nil), "/test.sock", "crictl")
if fcmd.RunCalls != 3 {
t.Errorf("expected 3 calls to Run, got %d", fcmd.RunCalls)
}
if !strings.Contains(fcmd.RunLog[1][0], "crictl") {
t.Errorf("expected a call to crictl, got %v", fcmd.RunLog[0])
}
if !strings.Contains(fcmd.RunLog[2][0], "crictl") {
t.Errorf("expected a call to crictl, got %v", fcmd.RunLog[0])
}
// 3: socket path provided, crictl fails, reset with docker
resetWithCrictl(&fexec, newFakeDockerChecker(nil, nil), "/test.sock", "crictl")
if fcmd.RunCalls != 4 {
t.Errorf("expected 4 calls to Run, got %d", fcmd.RunCalls)
}
if !strings.Contains(fcmd.RunLog[3][2], "docker") {
t.Errorf("expected a call to docker, got %v", fcmd.RunLog[0])
}
// 4: running with no socket and docker fails (1x Run)
resetWithCrictl(&fexec, newFakeDockerChecker(nil, []error{errors.New("test error")}), "", "crictl")
if fcmd.RunCalls != 4 {
t.Errorf("expected 4 calls to Run, got %d", fcmd.RunCalls)
}
}
func TestReset(t *testing.T) {
fcmd := fakeexec.FakeCmd{
CombinedOutputScript: []fakeexec.FakeCombinedOutputAction{
func() ([]byte, error) { return []byte("1"), nil },
func() ([]byte, error) { return []byte("1"), nil },
func() ([]byte, error) { return []byte("1"), nil },
},
RunScript: []fakeexec.FakeRunAction{
func() ([]byte, []byte, error) { return nil, nil, nil },
func() ([]byte, []byte, error) { return nil, nil, nil },
func() ([]byte, []byte, error) { return nil, nil, nil },
@ -365,25 +264,9 @@ func TestReset(t *testing.T) {
func(cmd string, args ...string) exec.Cmd { return fakeexec.InitFakeCmd(&fcmd, cmd, args...) },
func(cmd string, args ...string) exec.Cmd { return fakeexec.InitFakeCmd(&fcmd, cmd, args...) },
func(cmd string, args ...string) exec.Cmd { return fakeexec.InitFakeCmd(&fcmd, cmd, args...) },
func(cmd string, args ...string) exec.Cmd { return fakeexec.InitFakeCmd(&fcmd, cmd, args...) },
},
LookPathFunc: func(cmd string) (string, error) { return cmd, nil },
LookPathFunc: func(cmd string) (string, error) { return "/usr/bin/crictl", nil },
}
reset(&fexec, newFakeDockerChecker(nil, nil), "/test.sock")
if fcmd.RunCalls != 2 {
t.Errorf("expected 2 call to Run, got %d", fcmd.RunCalls)
}
if !strings.Contains(fcmd.RunLog[0][0], "crictl") {
t.Errorf("expected a call to crictl, got %v", fcmd.RunLog[0])
}
fexec.LookPathFunc = func(cmd string) (string, error) { return "", errors.New("no crictl") }
reset(&fexec, newFakeDockerChecker(nil, nil), "/test.sock")
if fcmd.RunCalls != 3 {
t.Errorf("expected 3 calls to Run, got %d", fcmd.RunCalls)
}
if !strings.Contains(fcmd.RunLog[2][2], "docker") {
t.Errorf("expected a call to docker, got %v", fcmd.RunLog[0])
}
removeContainers(&fexec, "unix:///var/run/crio/crio.sock")
}

14
cmd/kubeadm/app/images/BUILD
View File

@ -8,33 +8,23 @@ load(
go_library(
name = "go_default_library",
srcs = [
"images.go",
"interface.go",
],
srcs = ["images.go"],
importpath = "k8s.io/kubernetes/cmd/kubeadm/app/images",
deps = [
"//cmd/kubeadm/app/apis/kubeadm:go_default_library",
"//cmd/kubeadm/app/apis/kubeadm/v1alpha3:go_default_library",
"//cmd/kubeadm/app/constants:go_default_library",
"//cmd/kubeadm/app/features:go_default_library",
"//cmd/kubeadm/app/util:go_default_library",
"//vendor/k8s.io/utils/exec:go_default_library",
],
)
go_test(
name = "go_default_test",
srcs = [
"images_test.go",
"interface_test.go",
],
srcs = ["images_test.go"],
embed = [":go_default_library"],
deps = [
"//cmd/kubeadm/app/apis/kubeadm:go_default_library",
"//cmd/kubeadm/app/apis/kubeadm/v1alpha3:go_default_library",
"//cmd/kubeadm/app/constants:go_default_library",
"//vendor/k8s.io/utils/exec:go_default_library",
],
)

89
cmd/kubeadm/app/images/interface.go
View File

@ -1,89 +0,0 @@
/*
Copyright 2018 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 images
import (
"fmt"
kubeadmapiv1alpha3 "k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm/v1alpha3"
utilsexec "k8s.io/utils/exec"
)
// Puller is an interface for pulling images
type Puller interface {
Pull(string) error
}
// Existence is an interface to determine if an image exists on the system
// A nil error means the image was found
type Existence interface {
Exists(string) error
}
// Images defines the set of behaviors needed for images relating to the CRI
type Images interface {
Puller
Existence
}
// CRInterfacer is a struct that interfaces with the container runtime
type CRInterfacer struct {
criSocket string
exec utilsexec.Interface
crictlPath string
dockerPath string
}
// NewCRInterfacer sets up and returns a CRInterfacer
func NewCRInterfacer(execer utilsexec.Interface, criSocket string) (*CRInterfacer, error) {
var crictlPath, dockerPath string
var err error
if criSocket != kubeadmapiv1alpha3.DefaultCRISocket {
if crictlPath, err = execer.LookPath("crictl"); err != nil {
return nil, fmt.Errorf("crictl is required for non docker container runtimes: %v", err)
}
} else {
// use the dockershim
if dockerPath, err = execer.LookPath("docker"); err != nil {
return nil, fmt.Errorf("`docker` is required when docker is the container runtime and the kubelet is not running: %v", err)
}
}
return &CRInterfacer{
exec: execer,
criSocket: criSocket,
crictlPath: crictlPath,
dockerPath: dockerPath,
}, nil
}
// Pull pulls the actual image using either crictl or docker
func (cri *CRInterfacer) Pull(image string) error {
if cri.criSocket != kubeadmapiv1alpha3.DefaultCRISocket {
return cri.exec.Command(cri.crictlPath, "-r", cri.criSocket, "pull", image).Run()
}
return cri.exec.Command(cri.dockerPath, "pull", image).Run()
}
// Exists checks to see if the image exists on the system already
// Returns an error if the image is not found.
func (cri *CRInterfacer) Exists(image string) error {
if cri.criSocket != kubeadmapiv1alpha3.DefaultCRISocket {
return cri.exec.Command(cri.crictlPath, "-r", cri.criSocket, "inspecti", image).Run()
}
return cri.exec.Command(cri.dockerPath, "inspect", image).Run()
}

266
cmd/kubeadm/app/images/interface_test.go
View File

@ -1,266 +0,0 @@
/*
Copyright 2018 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 images_test
import (
"context"
"errors"
"io"
"testing"
kubeadmapiv1alpha3 "k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm/v1alpha3"
"k8s.io/kubernetes/cmd/kubeadm/app/images"
"k8s.io/utils/exec"
)
type fakeCmd struct {
err error
}
func (f *fakeCmd) Run() error {
return f.err
}
func (f *fakeCmd) CombinedOutput() ([]byte, error) { return nil, nil }
func (f *fakeCmd) Output() ([]byte, error) { return nil, nil }
func (f *fakeCmd) SetDir(dir string) {}
func (f *fakeCmd) SetStdin(in io.Reader) {}
func (f *fakeCmd) SetStdout(out io.Writer) {}
func (f *fakeCmd) SetStderr(out io.Writer) {}
func (f *fakeCmd) Stop() {}
type fakeExecer struct {
cmd exec.Cmd
findCrictl bool
findDocker bool
}
func (f *fakeExecer) Command(cmd string, args ...string) exec.Cmd { return f.cmd }
func (f *fakeExecer) CommandContext(ctx context.Context, cmd string, args ...string) exec.Cmd {
return f.cmd
}
func (f *fakeExecer) LookPath(file string) (string, error) {
if file == "crictl" {
if f.findCrictl {
return "/path", nil
}
return "", errors.New("no crictl for you")
}
if file == "docker" {
if f.findDocker {
return "/path", nil
}
return "", errors.New("no docker for you")
}
return "", errors.New("unknown binary")
}
func TestNewCRInterfacer(t *testing.T) {
testcases := []struct {
name string
criSocket string
findCrictl bool
findDocker bool
expectError bool
}{
{
name: "need crictl but can only find docker should return an error",
criSocket: "/not/docker",
findCrictl: false,
findDocker: true,
expectError: true,
},
{
name: "need crictl and cannot find either should return an error",
criSocket: "/not/docker",
findCrictl: false,
findDocker: false,
expectError: true,
},
{
name: "need crictl and cannot find docker should return no error",
criSocket: "/not/docker",
findCrictl: true,
findDocker: false,
expectError: false,
},
{
name: "need crictl and can find both should return no error",
criSocket: "/not/docker",
findCrictl: true,
findDocker: true,
expectError: false,
},
{
name: "need docker and cannot find crictl should return no error",
criSocket: kubeadmapiv1alpha3.DefaultCRISocket,
findCrictl: false,
findDocker: true,
expectError: false,
},
{
name: "need docker and cannot find docker should return an error",
criSocket: kubeadmapiv1alpha3.DefaultCRISocket,
findCrictl: false,
findDocker: false,
expectError: true,
},
{
name: "need docker and can find both should return no error",
criSocket: kubeadmapiv1alpha3.DefaultCRISocket,
findCrictl: true,
findDocker: true,
expectError: false,
},
{
name: "need docker and can only find crictl should return an error",
criSocket: kubeadmapiv1alpha3.DefaultCRISocket,
findCrictl: true,
findDocker: false,
expectError: true,
},
}
for _, tc := range testcases {
t.Run(tc.name, func(t *testing.T) {
fe := &fakeExecer{
findCrictl: tc.findCrictl,
findDocker: tc.findDocker,
}
_, err := images.NewCRInterfacer(fe, tc.criSocket)
if tc.expectError && err == nil {
t.Fatal("expected an error but did not get one")
}
if !tc.expectError && err != nil {
t.Fatalf("did not expedt an error but got an error: %v", err)
}
})
}
}
func TestImagePuller(t *testing.T) {
testcases := []struct {
name string
criSocket string
pullFails bool
errorExpected bool
}{
{
name: "using docker and pull fails",
criSocket: kubeadmapiv1alpha3.DefaultCRISocket,
pullFails: true,
errorExpected: true,
},
{
name: "using docker and pull succeeds",
criSocket: kubeadmapiv1alpha3.DefaultCRISocket,
pullFails: false,
errorExpected: false,
},
{
name: "using crictl pull fails",
criSocket: "/not/default",
pullFails: true,
errorExpected: true,
},
{
name: "using crictl and pull succeeds",
criSocket: "/not/default",
pullFails: false,
errorExpected: false,
},
}
for _, tc := range testcases {
t.Run(tc.name, func(t *testing.T) {
var err error
if tc.pullFails {
err = errors.New("error")
}
fe := &fakeExecer{
cmd: &fakeCmd{err},
findCrictl: true,
findDocker: true,
}
ip, _ := images.NewCRInterfacer(fe, tc.criSocket)
err = ip.Pull("imageName")
if tc.errorExpected && err == nil {
t.Fatal("expected an error and did not get one")
}
if !tc.errorExpected && err != nil {
t.Fatalf("expected no error but got one: %v", err)
}
})
}
}
func TestImageExists(t *testing.T) {
testcases := []struct {
name string
criSocket string
existFails bool
errorExpected bool
}{
{
name: "using docker and exist fails",
criSocket: kubeadmapiv1alpha3.DefaultCRISocket,
existFails: true,
errorExpected: true,
},
{
name: "using docker and exist succeeds",
criSocket: kubeadmapiv1alpha3.DefaultCRISocket,
existFails: false,
errorExpected: false,
},
{
name: "using crictl exist fails",
criSocket: "/not/default",
existFails: true,
errorExpected: true,
},
{
name: "using crictl and exist succeeds",
criSocket: "/not/default",
existFails: false,
errorExpected: false,
},
}
for _, tc := range testcases {
t.Run(tc.name, func(t *testing.T) {
var err error
if tc.existFails {
err = errors.New("error")
}
fe := &fakeExecer{
cmd: &fakeCmd{err},
findCrictl: true,
findDocker: true,
}
ip, _ := images.NewCRInterfacer(fe, tc.criSocket)
err = ip.Exists("imageName")
if tc.errorExpected && err == nil {
t.Fatal("expected an error and did not get one")
}
if !tc.errorExpected && err != nil {
t.Fatalf("expected no error but got one: %v", err)
}
})
}
}

4
cmd/kubeadm/app/preflight/BUILD
View File

@ -17,9 +17,9 @@ go_library(
importpath = "k8s.io/kubernetes/cmd/kubeadm/app/preflight",
deps = [
"//cmd/kubeadm/app/apis/kubeadm:go_default_library",
"//cmd/kubeadm/app/apis/kubeadm/v1alpha3:go_default_library",
"//cmd/kubeadm/app/constants:go_default_library",
"//cmd/kubeadm/app/images:go_default_library",
"//cmd/kubeadm/app/util/runtime:go_default_library",
"//cmd/kubeadm/app/util/system:go_default_library",
"//pkg/registry/core/service/ipallocator:go_default_library",
"//pkg/util/initsystem:go_default_library",
@ -44,6 +44,8 @@ go_test(
embed = [":go_default_library"],
deps = [
"//cmd/kubeadm/app/apis/kubeadm:go_default_library",
"//cmd/kubeadm/app/apis/kubeadm/v1alpha3:go_default_library",
"//cmd/kubeadm/app/util/runtime:go_default_library",
"//staging/src/k8s.io/apimachinery/pkg/util/sets:go_default_library",
"//vendor/github.com/renstrom/dedent:go_default_library",
"//vendor/k8s.io/utils/exec:go_default_library",

73
cmd/kubeadm/app/preflight/checks.go
View File

@ -42,9 +42,9 @@ import (
netutil "k8s.io/apimachinery/pkg/util/net"
"k8s.io/apimachinery/pkg/util/sets"
kubeadmapi "k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm"
kubeadmapiv1alpha3 "k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm/v1alpha3"
kubeadmconstants "k8s.io/kubernetes/cmd/kubeadm/app/constants"
"k8s.io/kubernetes/cmd/kubeadm/app/images"
utilruntime "k8s.io/kubernetes/cmd/kubeadm/app/util/runtime"
"k8s.io/kubernetes/cmd/kubeadm/app/util/system"
"k8s.io/kubernetes/pkg/registry/core/service/ipallocator"
"k8s.io/kubernetes/pkg/util/initsystem"
@ -90,28 +90,21 @@ type Checker interface {
Name() string
}
// CRICheck verifies the container runtime through the CRI.
type CRICheck struct {
socket string
exec utilsexec.Interface
// ContainerRuntimeCheck verifies the container runtime.
type ContainerRuntimeCheck struct {
runtime utilruntime.ContainerRuntime
}
// Name returns label for CRICheck.
func (CRICheck) Name() string {
// Name returns label for RuntimeCheck.
func (ContainerRuntimeCheck) Name() string {
return "CRI"
}
// Check validates the container runtime through the CRI.
func (criCheck CRICheck) Check() (warnings, errors []error) {
glog.V(1).Infoln("validating the container runtime through the CRI")
crictlPath, err := criCheck.exec.LookPath("crictl")
if err != nil {
errors = append(errors, fmt.Errorf("unable to find command crictl: %s", err))
return warnings, errors
}
if err := criCheck.exec.Command(crictlPath, "-r", criCheck.socket, "info").Run(); err != nil {
errors = append(errors, fmt.Errorf("unable to check if the container runtime at %q is running: %s", criCheck.socket, err))
return warnings, errors
// Check validates the container runtime
func (crc ContainerRuntimeCheck) Check() (warnings, errors []error) {
glog.V(1).Infoln("validating the container runtime")
if err := crc.runtime.IsRunning(); err != nil {
errors = append(errors, err)
}
return warnings, errors
}
@ -510,7 +503,7 @@ func (subnet HTTPProxyCIDRCheck) Check() (warnings, errors []error) {
// SystemVerificationCheck defines struct used for for running the system verification node check in test/e2e_node/system
type SystemVerificationCheck struct {
CRISocket string
IsDocker bool
}
// Name will return SystemVerification as name for SystemVerificationCheck
@ -532,9 +525,8 @@ func (sysver SystemVerificationCheck) Check() (warnings, errors []error) {
var validators = []system.Validator{
&system.KernelValidator{Reporter: reporter}}
// run the docker validator only with dockershim
if sysver.CRISocket == kubeadmapiv1alpha3.DefaultCRISocket {
// https://github.com/kubernetes/kubeadm/issues/533
// run the docker validator only with docker runtime
if sysver.IsDocker {
validators = append(validators, &system.DockerValidator{Reporter: reporter})
}
@ -825,8 +817,8 @@ func getEtcdVersionResponse(client *http.Client, url string, target interface{})
// ImagePullCheck will pull container images used by kubeadm
type ImagePullCheck struct {
Images images.Images
ImageList []string
runtime utilruntime.ContainerRuntime
imageList []string
}
// Name returns the label for ImagePullCheck
@ -835,14 +827,18 @@ func (ImagePullCheck) Name() string {
}
// Check pulls images required by kubeadm. This is a mutating check
func (i ImagePullCheck) Check() (warnings, errors []error) {
for _, image := range i.ImageList {
func (ipc ImagePullCheck) Check() (warnings, errors []error) {
for _, image := range ipc.imageList {
glog.V(1).Infoln("pulling ", image)
if err := i.Images.Exists(image); err == nil {
ret, err := ipc.runtime.ImageExists(image)
if ret && err == nil {
continue
}
if err := i.Images.Pull(image); err != nil {
errors = append(errors, fmt.Errorf("failed to pull image [%s]: %v", image, err))
if err != nil {
errors = append(errors, fmt.Errorf("failed to check if image %s exists: %v", image, err))
}
if err := ipc.runtime.PullImage(image); err != nil {
errors = append(errors, fmt.Errorf("failed to pull image %s: %v", image, err))
}
}
return warnings, errors
@ -957,11 +953,16 @@ func RunJoinNodeChecks(execer utilsexec.Interface, cfg *kubeadmapi.JoinConfigura
// addCommonChecks is a helper function to deplicate checks that are common between both the
// kubeadm init and join commands
func addCommonChecks(execer utilsexec.Interface, cfg kubeadmapi.CommonConfiguration, checks []Checker) []Checker {
// Check whether or not the CRI socket defined is the default
if cfg.GetCRISocket() != kubeadmapiv1alpha3.DefaultCRISocket {
checks = append(checks, CRICheck{socket: cfg.GetCRISocket(), exec: execer})
containerRuntime, err := utilruntime.NewContainerRuntime(execer, cfg.GetCRISocket())
isDocker := false
if err != nil {
fmt.Printf("[preflight] WARNING: Couldn't create the interface used for talking to the container runtime: %v\n", err)
} else {
checks = append(checks, ServiceCheck{Service: "docker", CheckIfActive: true})
checks = append(checks, ContainerRuntimeCheck{runtime: containerRuntime})
if containerRuntime.IsDocker() {
isDocker = true
checks = append(checks, ServiceCheck{Service: "docker", CheckIfActive: true})
}
}
// non-windows checks
@ -982,7 +983,7 @@ func addCommonChecks(execer utilsexec.Interface, cfg kubeadmapi.CommonConfigurat
InPathCheck{executable: "touch", mandatory: false, exec: execer})
}
checks = append(checks,
SystemVerificationCheck{CRISocket: cfg.GetCRISocket()},
SystemVerificationCheck{IsDocker: isDocker},
IsPrivilegedUserCheck{},
HostnameCheck{nodeName: cfg.GetNodeName()},
KubeletVersionCheck{KubernetesVersion: cfg.GetKubernetesVersion(), exec: execer},
@ -1002,13 +1003,13 @@ func RunRootCheckOnly(ignorePreflightErrors sets.String) error {
// RunPullImagesCheck will pull images kubeadm needs if the are not found on the system
func RunPullImagesCheck(execer utilsexec.Interface, cfg *kubeadmapi.InitConfiguration, ignorePreflightErrors sets.String) error {
criInterfacer, err := images.NewCRInterfacer(execer, cfg.GetCRISocket())
containerRuntime, err := utilruntime.NewContainerRuntime(utilsexec.New(), cfg.GetCRISocket())
if err != nil {
return err
}
checks := []Checker{
ImagePullCheck{Images: criInterfacer, ImageList: images.GetAllImages(cfg)},
ImagePullCheck{runtime: containerRuntime, imageList: images.GetAllImages(cfg)},
}
return RunChecks(checks, os.Stderr, ignorePreflightErrors)
}

64
cmd/kubeadm/app/preflight/checks_test.go
View File

@ -18,7 +18,6 @@ package preflight
import (
"bytes"
"errors"
"fmt"
"io/ioutil"
"strings"
@ -31,6 +30,8 @@ import (
"k8s.io/apimachinery/pkg/util/sets"
kubeadmapi "k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm"
kubeadmapiv1alpha3 "k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm/v1alpha3"
utilruntime "k8s.io/kubernetes/cmd/kubeadm/app/util/runtime"
"k8s.io/utils/exec"
fakeexec "k8s.io/utils/exec/testing"
)
@ -698,27 +699,50 @@ func TestSetHasItemOrAll(t *testing.T) {
}
}
type imgs struct{}
func (i *imgs) Pull(image string) error {
if image == "bad pull" {
return errors.New("pull error")
}
return nil
}
func (i *imgs) Exists(image string) error {
if image == "found" {
return nil
}
return errors.New("error")
}
func TestImagePullCheck(t *testing.T) {
i := ImagePullCheck{
Images: &imgs{},
ImageList: []string{"found", "not found", "bad pull"},
fcmd := fakeexec.FakeCmd{
RunScript: []fakeexec.FakeRunAction{
func() ([]byte, []byte, error) { return nil, nil, nil }, // Test case 1
func() ([]byte, []byte, error) { return nil, nil, nil },
func() ([]byte, []byte, error) { return nil, nil, nil },
func() ([]byte, []byte, error) { return nil, nil, &fakeexec.FakeExitError{Status: 1} }, // Test case 2
func() ([]byte, []byte, error) { return nil, nil, nil },
func() ([]byte, []byte, error) { return nil, nil, nil },
func() ([]byte, []byte, error) { return nil, nil, nil },
},
}
warnings, errors := i.Check()
fexec := fakeexec.FakeExec{
CommandScript: []fakeexec.FakeCommandAction{
func(cmd string, args ...string) exec.Cmd { return fakeexec.InitFakeCmd(&fcmd, cmd, args...) },
func(cmd string, args ...string) exec.Cmd { return fakeexec.InitFakeCmd(&fcmd, cmd, args...) },
func(cmd string, args ...string) exec.Cmd { return fakeexec.InitFakeCmd(&fcmd, cmd, args...) },
func(cmd string, args ...string) exec.Cmd { return fakeexec.InitFakeCmd(&fcmd, cmd, args...) },
func(cmd string, args ...string) exec.Cmd { return fakeexec.InitFakeCmd(&fcmd, cmd, args...) },
func(cmd string, args ...string) exec.Cmd { return fakeexec.InitFakeCmd(&fcmd, cmd, args...) },
func(cmd string, args ...string) exec.Cmd { return fakeexec.InitFakeCmd(&fcmd, cmd, args...) },
},
LookPathFunc: func(cmd string) (string, error) { return "/usr/bin/docker", nil },
}
containerRuntime, err := utilruntime.NewContainerRuntime(&fexec, kubeadmapiv1alpha3.DefaultCRISocket)
if err != nil {
t.Errorf("unexpected NewContainerRuntime error: %v", err)
}
check := ImagePullCheck{
runtime: containerRuntime,
imageList: []string{"img1", "img2", "img3"},
}
warnings, errors := check.Check()
if len(warnings) != 0 {
t.Fatalf("did not expect any warnings but got %q", warnings)
}
if len(errors) != 0 {
t.Fatalf("expected 1 errors but got %d: %q", len(errors), errors)
}
warnings, errors = check.Check()
if len(warnings) != 0 {
t.Fatalf("did not expect any warnings but got %q", warnings)
}

1
cmd/kubeadm/app/util/BUILD
View File

@ -77,6 +77,7 @@ filegroup(
"//cmd/kubeadm/app/util/etcd:all-srcs",
"//cmd/kubeadm/app/util/kubeconfig:all-srcs",
"//cmd/kubeadm/app/util/pubkeypin:all-srcs",
"//cmd/kubeadm/app/util/runtime:all-srcs",
"//cmd/kubeadm/app/util/staticpod:all-srcs",
"//cmd/kubeadm/app/util/system:all-srcs",
],

38
cmd/kubeadm/app/util/runtime/BUILD Normal file
View File

@ -0,0 +1,38 @@
load("@io_bazel_rules_go//go:def.bzl", "go_library", "go_test")
go_library(
name = "go_default_library",
srcs = ["runtime.go"],
importpath = "k8s.io/kubernetes/cmd/kubeadm/app/util/runtime",
visibility = ["//visibility:public"],
deps = [
"//cmd/kubeadm/app/apis/kubeadm/v1alpha3:go_default_library",
"//staging/src/k8s.io/apimachinery/pkg/util/errors:go_default_library",
"//vendor/k8s.io/utils/exec:go_default_library",
],
)
go_test(
name = "go_default_test",
srcs = ["runtime_test.go"],
embed = [":go_default_library"],
deps = [
"//cmd/kubeadm/app/apis/kubeadm/v1alpha3:go_default_library",
"//vendor/k8s.io/utils/exec:go_default_library",
"//vendor/k8s.io/utils/exec/testing:go_default_library",
],
)
filegroup(
name = "package-srcs",
srcs = glob(["**"]),
tags = ["automanaged"],
visibility = ["//visibility:private"],
)
filegroup(
name = "all-srcs",
srcs = [":package-srcs"],
tags = ["automanaged"],
visibility = ["//visibility:public"],
)

175
cmd/kubeadm/app/util/runtime/runtime.go Normal file
View File

@ -0,0 +1,175 @@
/*
Copyright 2018 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 util
import (
"fmt"
"path/filepath"
goruntime "runtime"
"strings"
"k8s.io/apimachinery/pkg/util/errors"
kubeadmapiv1alpha3 "k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm/v1alpha3"
utilsexec "k8s.io/utils/exec"
)
// ContainerRuntime is an interface for working with container runtimes
type ContainerRuntime interface {
IsDocker() bool
IsRunning() error
ListKubeContainers() ([]string, error)
RemoveContainers(containers []string) error
PullImage(image string) error
ImageExists(image string) (bool, error)
}
// CRIRuntime is a struct that interfaces with the CRI
type CRIRuntime struct {
exec utilsexec.Interface
criSocket string
}
// DockerRuntime is a struct that interfaces with the Docker daemon
type DockerRuntime struct {
exec utilsexec.Interface
}
// NewContainerRuntime sets up and returns a ContainerRuntime struct
func NewContainerRuntime(execer utilsexec.Interface, criSocket string) (ContainerRuntime, error) {
var toolName string
var runtime ContainerRuntime
if criSocket != kubeadmapiv1alpha3.DefaultCRISocket {
toolName = "crictl"
// !!! temporary work around crictl warning:
// Using "/var/run/crio/crio.sock" as endpoint is deprecated,
// please consider using full url format "unix:///var/run/crio/crio.sock"
if filepath.IsAbs(criSocket) && goruntime.GOOS != "windows" {
criSocket = "unix://" + criSocket
}
runtime = &CRIRuntime{execer, criSocket}
} else {
toolName = "docker"
runtime = &DockerRuntime{execer}
}
if _, err := execer.LookPath(toolName); err != nil {
return nil, fmt.Errorf("%s is required for container runtime: %v", toolName, err)
}
return runtime, nil
}
// IsDocker returns true if the runtime is docker
func (runtime *CRIRuntime) IsDocker() bool {
return false
}
// IsDocker returns true if the runtime is docker
func (runtime *DockerRuntime) IsDocker() bool {
return true
}
// IsRunning checks if runtime is running
func (runtime *CRIRuntime) IsRunning() error {
if err := runtime.exec.Command("crictl", "-r", runtime.criSocket, "info").Run(); err != nil {
return fmt.Errorf("container runtime is not running: %v", err)
}
return nil
}
// IsRunning checks if runtime is running
func (runtime *DockerRuntime) IsRunning() error {
if err := runtime.exec.Command("docker", "info").Run(); err != nil {
return fmt.Errorf("container runtime is not running: %v", err)
}
return nil
}
// ListKubeContainers lists running k8s CRI pods
func (runtime *CRIRuntime) ListKubeContainers() ([]string, error) {
output, err := runtime.exec.Command("crictl", "-r", runtime.criSocket, "pods", "-q").CombinedOutput()
if err != nil {
return nil, err
}
pods := []string{}
for _, pod := range strings.Fields(string(output)) {
if strings.HasPrefix(pod, "k8s_") {
pods = append(pods, pod)
}
}
return pods, nil
}
// ListKubeContainers lists running k8s containers
func (runtime *DockerRuntime) ListKubeContainers() ([]string, error) {
output, err := runtime.exec.Command("docker", "ps", "-a", "--filter", "name=k8s_", "-q").CombinedOutput()
return strings.Fields(string(output)), err
}
// RemoveContainers removes running k8s pods
func (runtime *CRIRuntime) RemoveContainers(containers []string) error {
errs := []error{}
for _, container := range containers {
err := runtime.exec.Command("crictl", "-r", runtime.criSocket, "stopp", container).Run()
if err != nil {
// don't stop on errors, try to remove as many containers as possible
errs = append(errs, fmt.Errorf("failed to stop running pod %s: %v", container, err))
} else {
err = runtime.exec.Command("crictl", "-r", runtime.criSocket, "rmp", container).Run()
if err != nil {
errs = append(errs, fmt.Errorf("failed to remove running container %s: %v", container, err))
}
}
}
return errors.NewAggregate(errs)
}
// RemoveContainers removes running containers
func (runtime *DockerRuntime) RemoveContainers(containers []string) error {
errs := []error{}
for _, container := range containers {
err := runtime.exec.Command("docker", "rm", "--force", "--volumes", container).Run()
if err != nil {
// don't stop on errors, try to remove as many containers as possible
errs = append(errs, fmt.Errorf("failed to remove running container %s: %v", container, err))
}
}
return errors.NewAggregate(errs)
}
// PullImage pulls the image
func (runtime *CRIRuntime) PullImage(image string) error {
return runtime.exec.Command("crictl", "-r", runtime.criSocket, "pull", image).Run()
}
// PullImage pulls the image
func (runtime *DockerRuntime) PullImage(image string) error {
return runtime.exec.Command("docker", "pull", image).Run()
}
// ImageExists checks to see if the image exists on the system
func (runtime *CRIRuntime) ImageExists(image string) (bool, error) {
err := runtime.exec.Command("crictl", "-r", runtime.criSocket, "inspecti", image).Run()
return err == nil, err
}
// ImageExists checks to see if the image exists on the system
func (runtime *DockerRuntime) ImageExists(image string) (bool, error) {
err := runtime.exec.Command("docker", "inspect", image).Run()
return err == nil, err
}