AB#2439 Containerized libvirt (#191)

Signed-off-by: Daniel Weiße <dw@edgeless.systems>

cli/internal/libvirt/libvirt.go

@@ -0,0 +1,97 @@
+/*
+Copyright (c) Edgeless Systems GmbH
+
+SPDX-License-Identifier: AGPL-3.0-only
+*/
+
+package libvirt
+
+import (
+	"context"
+	"errors"
+
+	"github.com/docker/docker/api/types"
+	"github.com/docker/docker/api/types/container"
+	docker "github.com/docker/docker/client"
+	"github.com/edgelesssys/constellation/v2/internal/file"
+	"github.com/spf13/afero"
+)
+
+// Runner handles starting and stopping of containerized libvirt instances.
+type Runner struct {
+	nameFile string
+	file     file.Handler
+}
+
+// New creates a new LibvirtRunner.
+func New() *Runner {
+	return &Runner{
+		nameFile: "libvirt.name",
+		file:     file.NewHandler(afero.NewOsFs()),
+	}
+}
+
+// Start starts a containerized libvirt instance.
+func (r *Runner) Start(ctx context.Context, name, imageName string) error {
+	docker, err := docker.NewClientWithOpts(docker.FromEnv, docker.WithAPIVersionNegotiation())
+	if err != nil {
+		return err
+	}
+	defer docker.Close()
+
+	containerName := name + "-libvirt"
+	if _, err := docker.ContainerCreate(ctx,
+		&container.Config{
+			Image: imageName,
+		},
+		&container.HostConfig{
+			NetworkMode: container.NetworkMode("host"),
+			AutoRemove:  true,
+			// container has to be "privileged" so libvirt has access to proc fs
+			Privileged: true,
+		},
+		nil,
+		nil,
+		containerName,
+	); err != nil {
+		return err
+	}
+	if err := docker.ContainerStart(ctx, containerName, types.ContainerStartOptions{}); err != nil {
+		_ = docker.ContainerRemove(ctx, containerName, types.ContainerRemoveOptions{Force: true})
+		return err
+	}
+
+	if err := r.file.Write(r.nameFile, []byte(containerName)); err != nil {
+		_ = docker.ContainerRemove(ctx, containerName, types.ContainerRemoveOptions{Force: true})
+		return err
+	}
+
+	// time.Sleep(15 * time.Second)
+
+	return nil
+}
+
+// Stop stops a containerized libvirt instance.
+func (r *Runner) Stop(ctx context.Context) error {
+	name, err := r.file.Read(r.nameFile)
+	if err != nil {
+		if errors.Is(err, afero.ErrFileNotFound) {
+			return nil
+		}
+		return err
+	}
+
+	docker, err := docker.NewClientWithOpts(docker.FromEnv, docker.WithAPIVersionNegotiation())
+	if err != nil {
+		return err
+	}
+	defer docker.Close()
+	if err := docker.ContainerRemove(ctx, string(name), types.ContainerRemoveOptions{Force: true}); err != nil {
+		return err
+	}
+
+	if err := r.file.Remove(r.nameFile); err != nil && !errors.Is(err, afero.ErrFileNotFound) {
+		return err
+	}
+	return nil
+}