feat: direct image build on containerd via docker-env

Author: ComradeProgrammer

Diff for: cmd/minikube/cmd/docker-env.go

@@ -287,13 +287,16 @@ docker-cli install instructions: https://minikube.sigs.k8s.io/docs/tutorials/doc
 			exit.Message(reason.EnvMultiConflict, `The docker-env command is incompatible with multi-node clusters. Use the 'registry' add-on: https://minikube.sigs.k8s.io/docs/handbook/registry/`)
 		}
 
-		if co.Config.KubernetesConfig.ContainerRuntime != constants.Docker {
-			exit.Message(reason.Usage, `The docker-env command is only compatible with the "docker" runtime, but this cluster was configured to use the "{{.runtime}}" runtime.`,
+		if co.Config.KubernetesConfig.ContainerRuntime != constants.Docker && co.Config.KubernetesConfig.ContainerRuntime != constants.Containerd {
+			exit.Message(reason.Usage, `The docker-env command is only compatible with the "docker" runtime or "containerd" runtime, but this cluster was configured to use the "{{.runtime}}" runtime.`,
 				out.V{"runtime": co.Config.KubernetesConfig.ContainerRuntime})
 		}
 
 		r := co.CP.Runner
-		ensureDockerd(cname, r)
+
+		if co.Config.KubernetesConfig.ContainerRuntime == constants.Docker {
+			ensureDockerd(cname, r)
+		}
 
 		d := co.CP.Host.Driver
 		port := constants.DockerDaemonPort

Diff for: cmd/minikube/cmd/start.go

@@ -26,11 +26,13 @@ import (
 	"os"
 	"os/exec"
 	"os/user"
+	"path/filepath"
 	"regexp"
 	"runtime"
 	"sort"
 	"strconv"
 	"strings"
+	"time"
 
 	"github.com/Delta456/box-cli-maker/v2"
 	"github.com/blang/semver/v4"
@@ -440,6 +442,11 @@ func startWithDriver(cmd *cobra.Command, starter node.Starter, existing *config.
 
 	pause.RemovePausedFile(starter.Runner)
 
+	//for the sake of docker-env command, download and start nerdctl and nerdctld
+	if starter.Cfg.KubernetesConfig.ContainerRuntime == constants.Containerd {
+		startNerdctld()
+	}
+
 	return kubeconfig, nil
 }
 
@@ -1779,3 +1786,61 @@ func exitGuestProvision(err error) {
 	}
 	exit.Error(reason.GuestProvision, "error provisioning guest", err)
 }
+
+func startNerdctld() {
+	//create a temporary directory
+	tmpDirName := "/tmp/minikube-nerdctld"
+	if err := os.Mkdir(tmpDirName, os.ModePerm); err != nil && !os.IsExist(err) {
+		exit.Error(reason.IfSSHClient, "Error with creating "+tmpDirName, err)
+	}
+
+	// for containerd runtime using ssh, we need to install nerdctld and nerdctl within os
+	if err := download.DownloadNerdctl(tmpDirName); err != nil {
+		exit.Error(reason.IfSSHClient, "Error with downloading nerdctl", err)
+	}
+	if err := download.DownloadNerdctld(tmpDirName); err != nil {
+		exit.Error(reason.IfSSHClient, "Error with downloading nerdctld", err)
+	}
+
+	//copy these binaries to the path of the containerd node
+	co := mustload.Running(ClusterFlagValue())
+	runner := co.CP.Runner
+	src := newRemotePath(filepath.Join(tmpDirName, "nerdctl"))
+	dst := newRemotePath("/usr/local/bin/nerdctl")
+	if err := runner.Copy(copyableFile(&co, src, dst)); err != nil {
+		exit.Error(reason.InternalCommandRunner, "Fail to copy file nerctl", err)
+	}
+
+	src = newRemotePath(filepath.Join(tmpDirName, "nerdctld"))
+	dst = newRemotePath("/usr/local/bin/nerdctld")
+	if err := runner.Copy(copyableFile(&co, src, dst)); err != nil {
+		exit.Error(reason.InternalCommandRunner, "Fail to copy file nerctld", err)
+	}
+
+	//and set 777 to these files
+	if out, err := runner.RunCmd(exec.Command("sudo", "chmod", "777", "/usr/local/bin/nerdctl", "/usr/local/bin/nerdctld")); err != nil {
+		exit.Error(reason.InternalCommandRunner, fmt.Sprintf("Fail to giver nerdctl proper permission: %s", out.Output()), err)
+	}
+
+	//start nerdctld
+	nerdctldDaemonCommand := exec.Command("/bin/bash", "-c", "sudo env CONTAINERD_NAMESPACE=k8s.io nohup nerdctld --socket=/var/run/nerdctld.sock >/dev/null 2>&1 &")
+	if out, err := runner.RunCmd(nerdctldDaemonCommand); err != nil {
+		exit.Error(reason.InternalCommandRunner, fmt.Sprintf("Fail to start nerdctld: %s", out.Output()), err)
+	}
+
+	//set up environment variable on remote machine. docker client uses 'non-login & non-interactive shell' therefore the only way is to modify .bashrc file of user 'docker'
+	// insert this at 4th line
+	envSetupCommand := exec.Command("/bin/bash", "-c", "sed -i '4i export DOCKER_HOST=unix:///var/run/nerdctld.sock' .bashrc")
+	if out, err := runner.RunCmd(envSetupCommand); err != nil {
+		exit.Error(reason.InternalCommandRunner, fmt.Sprintf("Fail to set up DOCKER_HOST: %s", out.Output()), err)
+	}
+
+	//need to wait for nerdctld to be started
+	time.Sleep(1 * time.Second)
+
+	//grant this socket proper permission. Docker daemon will automatically do that, but nerdctld won't
+	//user docker belongs to group "docker", while nerdctld.d doesn't , therefore nerdctld.sock needs to be visible outside the group
+	if out, err := runner.RunCmd(exec.Command("sudo", "chmod", "666", "/var/run/nerdctld.sock")); err != nil {
+		exit.Error(reason.InternalCommandRunner, fmt.Sprintf("Fail to grant permission to docker.sock: %s", out.Output()), err)
+	}
+}

Diff for: pkg/minikube/download/docker_env.go

@@ -0,0 +1,42 @@
+package download
+
+import (
+	"fmt"
+	"os"
+	"os/exec"
+	"path/filepath"
+)
+
+// DownloadNerdctl downloads nerdctl to directory specified by the param
+func DownloadNerdctl(dir string) error {
+	//check whether nerdctl exists
+	if _, err := os.Stat(filepath.Join(dir, "nerdctl")); err == nil {
+		//file exists
+		return nil
+	}
+	fileName := filepath.Join(dir, "nerdctl-1.0.0-linux-amd64.tar.gz")
+	if err := download("https://github.com/containerd/nerdctl/releases/download/v1.0.0/nerdctl-1.0.0-linux-amd64.tar.gz", fileName); err != nil {
+		return err
+	}
+	if err := exec.Command("tar", "-xvzf", fileName, "-C", dir).Run(); err != nil {
+		return fmt.Errorf("failed to untar nerdctl: %v", err)
+	}
+	return nil
+}
+
+// DownloadNerdctld downloads nerdctld to directory specified by the param
+func DownloadNerdctld(dir string) error {
+	//check whether nerdctld exists
+	if _, err := os.Stat(filepath.Join(dir, "nerdctld")); err == nil {
+		//file exists
+		return nil
+	}
+	fileName := filepath.Join(dir, "nerdctld-0.2.0-linux-amd64.tar.gz")
+	if err := download("https://github.com/afbjorklund/nerdctld/releases/download/v0.2.0/nerdctld-0.2.0-linux-amd64.tar.gz", fileName); err != nil {
+		return err
+	}
+	if err := exec.Command("tar", "-xvzf", fileName, "-C", dir).Run(); err != nil {
+		return fmt.Errorf("failed to untar nerdctd: %v", err)
+	}
+	return nil
+}

Diff for: pkg/minikube/download/download.go

@@ -72,11 +72,12 @@ func download(src string, dst string) error {
 	}
 	tmpDst := dst + ".download"
 	client := &getter.Client{
-		Src:     src,
-		Dst:     tmpDst,
-		Dir:     false,
-		Mode:    getter.ClientModeFile,
-		Options: clientOptions,
+		Src:           src,
+		Dst:           tmpDst,
+		Dir:           false,
+		Mode:          getter.ClientModeFile,
+		Options:       clientOptions,
+		Decompressors: map[string]getter.Decompressor{},
 		Getters: map[string]getter.Getter{
 			"file":  &getter.FileGetter{Copy: false},
 			"http":  &getter.HttpGetter{Netrc: false},

Diff for: test.txt

@@ -0,0 +1,6 @@
+aaaaaaaaaaaaaaaaaaa
+123qaz
+bbbbbbbbbbbbbbbbbbbb
+ccccccccccccccccccc
+ddddddddddddddddd
+eeeeeeeeeeeeeeeeeee