Local builder: Support shell out to docker build

Signed-off-by: David Gageot <[email protected]>

examples/annotated-skaffold.yaml

@@ -62,27 +62,35 @@ build:
 # This next section is where you'll put your specific builder configuration.
   # Valid builders are `local`, `googleCloudBuild` and `kaniko.
   # Defaults to `local: {}`
-  # Example
+
+  # Pushing the images can be skipped. If no value is specified, it'll default to
+  # `true` on minikube or Docker for Desktop, for even faster build and deploy cycles.
+  # `false` on other types of kubernetes clusters that require pushing the images.
+  # kaffold defers to your ~/.docker/config for authentication information.
+  # If you're using Google Container Registry, make sure that you have gcloud and
+  # docker-credentials-helper-gcr configured correctly.
+  #
+  # By default, the local builder connects to the Docker daemon with Go code to build
+  # images. If `useDockerCLI` is set, skaffold will simply shell out to the docker CLI.
+  # `useBuildkit` can also be set to activate the experimental BuildKit feature.
+  #
   # local:
-    # Pushing the images can be skipped. If no value is specified, it'll default to
-    # `true` on minikube or Docker for Desktop, for even faster build and deploy cycles.
-    # `false` on other types of kubernetes clusters that require pushing the images.
-    # Skaffold defers to your ~/.docker/config for authentication information.
-    # If you're using Google Container Registry, make sure that you have gcloud and
-    # docker-credentials-helper-gcr configured correctly.
-    # skipPush: true
+  #   skipPush: true
+  #   useDockerCLI: false
+  #   useBuildkit: false
 
   # Docker artifacts can be built on Google Container Builder. The projectId then needs
   # to be provided and the currently logged user should be given permissions to trigger
   # new builds on GCB.
+  #
   #  googleCloudBuild:
   #   projectId: YOUR_PROJECT
 
   # Docker artifacts can be built on a Kubernetes cluster with Kaniko.
   # Sources will be sent to a GCS bucket whose name is provided.
   # Kaniko also needs access to a service account to push the final image.
   # See https://github.com/GoogleContainerTools/kaniko#running-kaniko-in-a-kubernetes-cluster
-  # Example
+  #
   # kaniko:
   #   gcsBucket: k8s-skaffold
   #   pullSecret: /a/secret/path/serviceaccount.json

pkg/skaffold/build/docker.go

@@ -20,6 +20,9 @@ import (
 	"context"
 	"fmt"
 	"io"
+	"os"
+	"os/exec"
+	"path/filepath"
 
 	"github.com/GoogleContainerTools/skaffold/pkg/skaffold/docker"
 	"github.com/GoogleContainerTools/skaffold/pkg/skaffold/schema/v1alpha2"
@@ -31,12 +34,36 @@ import (
 func (l *LocalBuilder) buildDocker(ctx context.Context, out io.Writer, workspace string, a *v1alpha2.DockerArtifact) (string, error) {
 	initialTag := util.RandomID()
 
-	err := docker.RunBuild(ctx, out, l.api, workspace, types.ImageBuildOptions{
-		Tags:       []string{initialTag},
-		Dockerfile: a.DockerfilePath,
-		BuildArgs:  a.BuildArgs,
-		CacheFrom:  a.CacheFrom,
-	})
+	var err error
+	if l.cfg.UseDockerCLI || l.cfg.UseBuildkit {
+		absDockerfilePath := a.DockerfilePath
+		if !filepath.IsAbs(a.DockerfilePath) {
+			absDockerfilePath = filepath.Join(workspace, a.DockerfilePath)
+		}
+
+		args := []string{"build", workspace, "--file", absDockerfilePath, "-t", initialTag}
+		args = append(args, docker.GetBuildArgs(a)...)
+		for _, from := range a.CacheFrom {
+			args = append(args, "--cache-from", from)
+		}
+
+		cmd := exec.Command("docker", args...)
+		if l.cfg.UseBuildkit {
+			cmd.Env = append(os.Environ(), "DOCKER_BUILDKIT=1")
+		}
+		cmd.Stdout = out
+		cmd.Stderr = out
+
+		err = util.RunCmd(cmd)
+	} else {
+		err = docker.RunBuild(ctx, out, l.api, workspace, types.ImageBuildOptions{
+			Tags:       []string{initialTag},
+			Dockerfile: a.DockerfilePath,
+			BuildArgs:  a.BuildArgs,
+			CacheFrom:  a.CacheFrom,
+		})
+	}
+
 	if err != nil {
 		return "", errors.Wrap(err, "running build")
 	}

pkg/skaffold/build/local.go

@@ -31,6 +31,8 @@ import (
 
 // LocalBuilder uses the host docker daemon to build and tag the image
 type LocalBuilder struct {
+	cfg *v1alpha2.LocalBuild
+
 	api          docker.APIClient
 	localCluster bool
 	pushImages   bool
@@ -54,6 +56,7 @@ func NewLocalBuilder(cfg *v1alpha2.LocalBuild, kubeContext string) (*LocalBuilde
 	}
 
 	return &LocalBuilder{
+		cfg:          cfg,
 		kubeContext:  kubeContext,
 		api:          api,
 		localCluster: localCluster,

pkg/skaffold/build/local_test.go

@@ -182,6 +182,7 @@ func TestLocalRun(t *testing.T) {
 	for _, test := range tests {
 		t.Run(test.description, func(t *testing.T) {
 			l := LocalBuilder{
+				cfg:          test.config,
 				api:          test.api,
 				localCluster: test.localCluster,
 			}

pkg/skaffold/schema/v1alpha2/config.go

@@ -79,7 +79,9 @@ type BuildType struct {
 // LocalBuild contains the fields needed to do a build on the local docker daemon
 // and optionally push to a repository.
 type LocalBuild struct {
-	SkipPush *bool `yaml:"skipPush"`
+	SkipPush     *bool `yaml:"skipPush"`
+	UseDockerCLI bool  `yaml:"useDockerCLI"`
+	UseBuildkit  bool  `yaml:"useBuildkit"`
 }
 
 // GoogleCloudBuild contains the fields needed to do a remote build on