exec/docker/rootfs.go

package docker

import (
	"context"
	"io"

	"github.com/docker/docker/api/types/image"
	"github.com/docker/docker/client"
	"github.com/docker/go-connections/nat"
	"sirherobrine23.com.br/go-bds/exec"
)

var _ = exec.RegisterRootfs("docker", func(a ...any) (*Rootfs, error) {
	container := "debian:latest"
	var dockerClient *client.Client

	if len(a) > 0 {
		switch v := a[0].(type) {
		case string:
			container = v
		case *client.Client:
			dockerClient = v
			if len(a) > 1 {
				if cont, ok := a[1].(string); ok {
					container = cont
				}
			}
		}
	}

	if dockerClient == nil {
		var err error
		if dockerClient, err = client.NewClientWithOpts(client.FromEnv); err != nil {
			return nil, err
		}
	}

	return &Rootfs{
		DockerClient: dockerClient,
		DockerImage:  container,
	}, nil
})

type Rootfs struct {
	DockerClient *client.Client

	DockerImage string
}

func (rootfs *Rootfs) Close() error { return rootfs.DockerClient.Close() }

func (rootfs *Rootfs) Tar(w io.Writer) error {
	r, err := rootfs.DockerClient.ImageSave(context.Background(), []string{rootfs.DockerImage})
	if err != nil {
		return err
	}
	defer r.Close()
	_, err = io.Copy(w, r)
	return err
}

func (rootfs *Rootfs) FromTar(r io.Reader) error {
	r, err := rootfs.DockerClient.ImageImport(context.Background(), image.ImportSource{Source: r}, rootfs.DockerImage, image.ImportOptions{
		Changes: []string{
			"CMD /bin/sh",
		},
	})
	if err == nil {
		_, err = io.Copy(io.Discard, r)
	}
	return err
}

func (rootfs *Rootfs) NewProcess() (exec.Proc, error) {
	return &DockerContainer{
		DockerClient: rootfs.DockerClient,
		Image:        rootfs.DockerImage,
		Volumes:      []string{},
		Ports:        []nat.Port{},
	}, nil
}