Add some basic support for setting the image tag

cmd/minikube/cmd/build.go

@@ -25,6 +25,10 @@ import (
 	"k8s.io/minikube/pkg/minikube/reason"
 )
 
+var (
+	tag string
+)
+
 // buildCmd represents the build command
 var buildCmd = &cobra.Command{
 	Use:   "build",
@@ -42,11 +46,12 @@ minikube build .`,
 			exit.Error(reason.Usage, "loading profile", err)
 		}
 		img := args[0]
-		if err := machine.BuildImage(img, "test:latest", []*config.Profile{profile}); err != nil {
+		if err := machine.BuildImage(img, tag, []*config.Profile{profile}); err != nil {
 			exit.Error(reason.GuestImageBuild, "Failed to build image", err)
 		}
 	},
 }
 
 func init() {
+	buildCmd.Flags().StringVarP(&tag, "tag", "t", "", "Tag to apply to the new image (optional)")
 }

pkg/minikube/cruntime/containerd.go

@@ -280,11 +280,19 @@ func (r *Containerd) RemoveImage(name string) error {
 // BuildImage builds an image into this runtime
 func (r *Containerd) BuildImage(path string, tag string) error {
 	klog.Infof("Building image: %s", path)
+	opt := ""
+	if tag != "" {
+		// add default tag if missing
+		if !strings.Contains(tag, ":") {
+			tag += ":latest"
+		}
+		opt = fmt.Sprintf(",name=%s", tag)
+	}
 	c := exec.Command("sudo", "buildctl", "build",
 		"--frontend", "dockerfile.v0",
 		"--local", fmt.Sprintf("context=%s", path),
 		"--local", fmt.Sprintf("dockerfile=%s", path),
-		"--output", fmt.Sprintf("type=image,name=%s", tag))
+		"--output", fmt.Sprintf("type=image%s", opt))
 	if _, err := r.Runner.RunCmd(c); err != nil {
 		return errors.Wrap(err, "buildctl build.")
 	}

pkg/minikube/cruntime/crio.go

@@ -200,7 +200,11 @@ func (r *CRIO) RemoveImage(name string) error {
 // BuildImage builds an image into this runtime
 func (r *CRIO) BuildImage(path string, tag string) error {
 	klog.Infof("Building image: %s", path)
-	c := exec.Command("sudo", "podman", "build", "-t", tag, path)
+	args := []string{"podman", "build"}
+	if tag != "" {
+		args = append(args, "-t", tag)
+	}
+	c := exec.Command("sudo", args...)
 	if _, err := r.Runner.RunCmd(c); err != nil {
 		return errors.Wrap(err, "crio build image")
 	}

pkg/minikube/cruntime/docker.go

@@ -220,7 +220,11 @@ func (r *Docker) RemoveImage(name string) error {
 // BuildImage builds an image into this runtime
 func (r *Docker) BuildImage(path string, tag string) error {
 	klog.Infof("Building image: %s", path)
-	c := exec.Command("docker", "build", "-t", tag, path)
+	args := []string{"build"}
+	if tag != "" {
+		args = append(args, "-t", tag)
+	}
+	c := exec.Command("docker", args...)
 	if _, err := r.Runner.RunCmd(c); err != nil {
 		return errors.Wrap(err, "buildimage docker.")
 	}