Feature 2160 add images subcommand

pkg/build/addimage/build.go

@@ -0,0 +1,60 @@
+/*
+Copyright 2020 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 addimage
+
+import (
+	"runtime"
+
+	"sigs.k8s.io/kind/pkg/apis/config/defaults"
+	"sigs.k8s.io/kind/pkg/log"
+)
+
+// Build builds a node image using the supplied options
+func Build(options ...Option) error {
+	// default options
+	ctx := &buildContext{
+		image:     DefaultImage,
+		baseImage: defaults.Image,
+		logger:    log.NoopLogger{},
+		arch:      runtime.GOARCH,
+	}
+
+	// apply user options
+	for _, option := range options {
+		if err := option.apply(ctx); err != nil {
+			return err
+		}
+	}
+
+	// verify that we're using a supported arch
+	if !supportedArch(ctx.arch) {
+		ctx.logger.Warnf("unsupported architecture %q", ctx.arch)
+	}
+	return ctx.Build()
+}
+
+func supportedArch(arch string) bool {
+	switch arch {
+	default:
+		return false
+	// currently we nominally support building node images for these
+	case "amd64":
+	case "arm64":
+	case "ppc64le":
+	}
+	return true
+}

pkg/build/addimage/buildcontext.go

@@ -0,0 +1,177 @@
+/*
+Copyrigh. 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 addimage
+
+import (
+	"fmt"
+	"io"
+	"math/rand"
+	"os"
+	"path/filepath"
+	"strings"
+	"time"
+
+	"sigs.k8s.io/kind/pkg/build/addimage/internal/container/docker"
+	"sigs.k8s.io/kind/pkg/errors"
+	"sigs.k8s.io/kind/pkg/exec"
+	"sigs.k8s.io/kind/pkg/fs"
+	"sigs.k8s.io/kind/pkg/log"
+)
+
+// buildContext is used to build the kind node image, and contains
+// build configuration
+type buildContext struct {
+	// option fields
+	image            string
+	baseImage        string
+	additionalImages []string
+	logger           log.Logger
+	arch             string
+}
+
+// Build builds the cluster node image, the sourcedir must be set on
+// the buildContext
+func (c *buildContext) Build() (err error) {
+	return c.addImages()
+}
+
+func (c *buildContext) addImages() error {
+
+	c.logger.V(0).Info("Starting to add images to base image")
+	// pull images to local docker
+	for _, imageName := range c.additionalImages {
+		// continue if image already exists, no need to pull
+		_, err := docker.ImageID(imageName)
+		if err == nil {
+			continue
+		}
+
+		err = docker.Pull(c.logger, imageName, dockerBuildOsAndArch(c.arch), 3)
+		if err != nil {
+			c.logger.Errorf("Add image build Failed! Failed to pull image %v: %v", imageName, err)
+		}
+	}
+
+	// create build container
+	c.logger.V(0).Info("Creating build container based on " + c.baseImage)
+	// pull images to local docker
+	containerID, err := c.createBuildContainer()
+	// ensure we will delete it
+	if containerID != "" {
+		defer func() {
+			_ = exec.Command("docker", "rm", "-f", "-v", containerID).Run()
+		}()
+	}
+	if err != nil {
+		c.logger.Errorf("Image build Failed! Failed to create build container: %v", err)
+		return err
+	}
+	c.logger.V(0).Info("Building in " + containerID)
+
+	// For kubernetes v1.15+ (actually 1.16 alpha versions) we may need to
+	// drop the arch suffix from images to get the expected image
+	archSuffix := "-" + c.arch
+	fixRepository := func(repository string) string {
+		if strings.HasSuffix(repository, archSuffix) {
+			fixed := strings.TrimSuffix(repository, archSuffix)
+			c.logger.V(1).Info("fixed: " + repository + " -> " + fixed)
+			repository = fixed
+		}
+		return repository
+	}
+
+	// Tar up the images to make the load easier (and follow the current load pattern)
+	// Setup the tar path where the images will be saved
+	dir, err := fs.TempDir("", "images-tar")
+	if err != nil {
+		return errors.Wrap(err, "failed to create tempdir")
+	}
+	defer os.RemoveAll(dir)
+	imagesTarFile := filepath.Join(dir, "images.tar")
+	// Save the images into a tar file
+	c.logger.V(0).Info("Saving images into tar file at " + imagesTarFile)
+	err = docker.SaveImages(c.additionalImages, imagesTarFile)
+	if err != nil {
+		return err
+	}
+
+	// setup image importer
+	cmder := docker.ContainerCmder(containerID)
+	importer := newContainerdImporter(cmder)
+
+	f, err := os.Open(imagesTarFile)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+	//return importer.LoadCommand().SetStdout(os.Stdout).SetStderr(os.Stderr).SetStdin(f).Run()
+	// we will rewrite / correct the tags as we load the image
+	c.logger.V(0).Info("Importing images into build container " + containerID)
+	if err := exec.RunWithStdinWriter(importer.LoadCommand().SetStdout(os.Stdout).SetStderr(os.Stdout), func(w io.Writer) error {
+		return docker.EditArchive(f, w, fixRepository, c.arch)
+	}); err != nil {
+		return err
+	}
+
+	// Save the image changes to a new image
+	c.logger.V(0).Info("Saving new image " + c.image)
+	saveCmd := exec.Command(
+		"docker", "commit",
+		// we need to put this back after changing it when running the image
+		"--change", `ENTRYPOINT [ "/usr/local/bin/entrypoint", "/sbin/init" ]`,
+		containerID, c.image,
+	)
+	exec.InheritOutput(saveCmd)
+	if err = saveCmd.Run(); err != nil {
+		c.logger.Errorf("Add image build Failed! Failed to save image: %v", err)
+		return err
+	}
+
+	c.logger.V(0).Info("Add image build completed.")
+	return nil
+}
+
+func (c *buildContext) createBuildContainer() (id string, err error) {
+	// attempt to explicitly pull the image if it doesn't exist locally
+	// we don't care if this errors, we'll still try to run which also pulls
+	_ = docker.Pull(c.logger, c.baseImage, dockerBuildOsAndArch(c.arch), 4)
+	// this should be good enough: a specific prefix, the current unix time,
+	// and a little random bits in case we have multiple builds simultaneously
+	random := rand.New(rand.NewSource(time.Now().UnixNano())).Int31()
+	id = fmt.Sprintf("kind-build-%d-%d", time.Now().UTC().Unix(), random)
+	err = docker.Run(
+		c.baseImage,
+		[]string{
+			"-d", // make the client exit while the container continues to run
+			// run containerd so that the cri command works
+			"--entrypoint=/usr/local/bin/containerd",
+			"--name=" + id,
+			"--platform=" + dockerBuildOsAndArch(c.arch),
+		},
+		[]string{
+			"",
+		},
+	)
+	if err != nil {
+		return id, errors.Wrap(err, "failed to create build container")
+	}
+	return id, nil
+}
+
+func dockerBuildOsAndArch(arch string) string {
+	return "linux/" + arch
+}

pkg/build/addimage/const.go

@@ -0,0 +1,17 @@
+/*
+Copyright 2019 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 addimage

pkg/build/addimage/defaults.go

@@ -0,0 +1,20 @@
+/*
+Copyright 2020 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 addimage
+
+// DefaultImage is the default name:tag for the built image
+const DefaultImage = "kindest/custom-node:latest"

pkg/build/addimage/imageimporter.go

@@ -0,0 +1,38 @@
+/*
+Copyright 2019 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 addimage
+
+import (
+	"sigs.k8s.io/kind/pkg/exec"
+)
+
+type containerdImporter struct {
+	containerCmder exec.Cmder
+}
+
+func newContainerdImporter(containerCmder exec.Cmder) *containerdImporter {
+	return &containerdImporter{
+		containerCmder: containerCmder,
+	}
+}
+
+func (c *containerdImporter) LoadCommand() exec.Cmd {
+	return c.containerCmder.Command(
+		// TODO: ideally we do not need this in the future. we have fixed at least one image
+		"ctr", "--namespace=k8s.io", "images", "import", "--all-platforms", "--no-unpack", "-",
+	)
+}