build and convert implementations

centos: WIP

Signed-off-by: Adphi <philippe.adrien.nousse@gmail.com>

convert.go

@@ -0,0 +1,115 @@
+// Copyright 2022 Linka Cloud  All rights reserved.
+//
+// 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 docker2vm
+
+import (
+	"context"
+	"fmt"
+	"io"
+	"os"
+	"path/filepath"
+
+	"github.com/google/uuid"
+	"github.com/sirupsen/logrus"
+
+	"go.linka.cloud/d2vm/pkg/docker"
+)
+
+func Convert(ctx context.Context, img string, size int64, password string, output string) error {
+	imgUUID := uuid.New().String()
+	tmpPath := filepath.Join(os.TempDir(), "d2vm", imgUUID)
+	if err := os.MkdirAll(tmpPath, os.ModePerm); err != nil {
+		return err
+	}
+	defer os.RemoveAll(tmpPath)
+
+	logrus.Infof("inspecting image %s", img)
+	r, err := FetchDockerImageOSRelease(ctx, img, tmpPath)
+	if err != nil {
+		return err
+	}
+	d, err := NewDockerfile(r, img, password)
+	if err != nil {
+		return err
+	}
+	logrus.Infof("docker image based on %s", d.Release.Name)
+	p := filepath.Join(tmpPath, docker.FormatImgName(img))
+	dir := filepath.Dir(p)
+	f, err := os.Create(p)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+	if err := d.Render(f); err != nil {
+		return err
+	}
+	logrus.Infof("building kernel enabled image")
+	if err := docker.Cmd(ctx, "image", "build", "-t", imgUUID, "-f", p, dir); err != nil {
+		return err
+	}
+	defer docker.Cmd(ctx, "image", "rm", imgUUID)
+	archive := imgUUID + ".tar"
+	archivePath := filepath.Join(tmpPath, archive)
+	logrus.Infof("creating root file system archive")
+	if err := docker.Cmd(ctx, "run", "-d", "--name", imgUUID, imgUUID); err != nil {
+		return err
+	}
+	if err := docker.Cmd(ctx, "export", "--output", archivePath, imgUUID); err != nil {
+		return err
+	}
+	if err := docker.Cmd(ctx, "rm", "-f", imgUUID); err != nil {
+		return err
+	}
+	logrus.Infof("creating vm image")
+
+	b, err := NewBuilder(tmpPath, archivePath, "", size, r)
+	if err != nil {
+		return err
+	}
+	if err := b.Build(ctx); err != nil {
+		return err
+	}
+	if err := os.RemoveAll(output); err != nil {
+		return err
+	}
+	if err := MoveFile(filepath.Join(tmpPath, "disk0.qcow2"), output); err != nil {
+		return err
+	}
+	return nil
+}
+
+func MoveFile(sourcePath, destPath string) error {
+	inputFile, err := os.Open(sourcePath)
+	if err != nil {
+		return fmt.Errorf("failed to open source file: %s", err)
+	}
+	outputFile, err := os.Create(destPath)
+	if err != nil {
+		inputFile.Close()
+		return fmt.Errorf("failed to open dest file: %s", err)
+	}
+	defer outputFile.Close()
+	_, err = io.Copy(outputFile, inputFile)
+	inputFile.Close()
+	if err != nil {
+		return fmt.Errorf("failed to write to output file: %s", err)
+	}
+	// The copy was successful, so now delete the original file
+	err = os.Remove(sourcePath)
+	if err != nil {
+		return fmt.Errorf("failed to remove original file: %s", err)
+	}
+	return nil
+}