exec/docker/docker.go

// Run process insider a docker container
package docker

import (
	"context"
	"errors"
	"fmt"
	"io"
	"net/netip"
	"os"

	"github.com/docker/docker/pkg/stdcopy"
	"github.com/moby/moby/api/types/container"
	"github.com/moby/moby/api/types/network"
	"github.com/moby/moby/client"
	"sirherobrine23.com.br/go-bds/exec/v2/process"
)

// Register default client docker
var _ = process.RegisterProcess(NewProc, "docker")

type DockerContainer struct {
	DockerClient *client.Client

	ContainerName string
	Image         string
	Platform      string // Docker platform to run image
	Ports         []network.Port
	Volumes       []string

	containerID string
	statusExit  *container.WaitResponse
}

// Return new docker exec
func NewDocker(client *client.Client) *DockerContainer {
	return &DockerContainer{
		Image:        "debian:latest",
		DockerClient: client,
		Volumes:      []string{},
		Ports:        []network.Port{},
	}
}

// Create Docker client connection and return new DockerContainer with "debian:latest" image
func NewProc() (*DockerContainer, error) {
	client, err := client.New(client.FromEnv)
	if err != nil {
		return nil, err
	}
	return NewDocker(client), nil
}

// Append port on start conteiner
func (docker *DockerContainer) AddPort(networkType string, local, remote uint16) {
	switch networkType {
	case "udp", "udp4", "udp6":
		docker.Ports = append(docker.Ports, network.MustParsePort(fmt.Sprintf("%d:%d/udp", remote, local)))
	case "tcp", "tcp4", "tcp6":
		docker.Ports = append(docker.Ports, network.MustParsePort(fmt.Sprintf("%d:%d/tcp", remote, local)))
	default:
		docker.Ports = append(docker.Ports, network.MustParsePort(fmt.Sprintf("%d:%d", remote, local)))
	}
}

// Get container addresses
func (docker DockerContainer) ContainerAddr() ([]netip.Addr, error) {
	if docker.containerID == "" {
		return nil, process.ErrNoProcess
	}

	// Get container info
	info, err := docker.DockerClient.ContainerInspect(context.Background(), docker.containerID, client.ContainerInspectOptions{})
	if err != nil {
		return nil, err
	}

	// IP Addresses
	addr := []netip.Addr{}

	if info.Container.NetworkSettings != nil {
		if network := info.Container.NetworkSettings; len(info.Container.NetworkSettings.Networks) == 0 {
			for _, network := range network.Networks {
				if network.IPAddress.String() != "" {
					addr = append(addr, network.IPAddress)
				}

				if network.GlobalIPv6Address.String() != "" {
					addr = append(addr, network.GlobalIPv6Address)
				}

			}
		}
	}

	return addr, nil
}

func (docker *DockerContainer) Kill() error {
	if docker.containerID == "" {
		return process.ErrNoProcess
	}
	_, err := docker.DockerClient.ContainerKill(context.Background(), docker.containerID, client.ContainerKillOptions{Signal: "SIGKILL"})
	return err
}

func (docker *DockerContainer) Wait() error {
	if docker.containerID == "" {
		return process.ErrNoProcess
	}
	wait := docker.DockerClient.ContainerWait(context.Background(), docker.containerID, client.ContainerWaitOptions{Condition: container.WaitConditionNextExit})
	select {
	case err := <-wait.Error:
		if err != nil {
			return err
		}
	case status := <-wait.Result:
		docker.statusExit = &status
		if status.Error != nil {
			return errors.New(status.Error.Message)
		} else if status.StatusCode != 0 {
			return fmt.Errorf("exit code %d", status.StatusCode)
		}
	}

	return nil
}

func (docker *DockerContainer) ExitCode() (int, error) {
	if docker.statusExit != nil {
		return int(docker.statusExit.StatusCode), nil
	} else if docker.containerID == "" {
		return -1, process.ErrNoProcess
	}

	wait := docker.DockerClient.ContainerWait(context.Background(), docker.containerID, client.ContainerWaitOptions{Condition: container.WaitConditionNextExit})
	select {
	case err := <-wait.Error:
		if err != nil {
			return -1, err
		}
	case status := <-wait.Result:
		docker.statusExit = &status
		if status.Error != nil {
			return -1, errors.New(status.Error.Message)
		} else if status.StatusCode != 0 {
			return -1, fmt.Errorf("exit code %d", status.StatusCode)
		}
	}
	return int(docker.statusExit.StatusCode), nil
}

func (docker *DockerContainer) Close() error {
	if docker.containerID == "" {
		return process.ErrNoProcess
	} else if _, err := docker.DockerClient.ContainerStop(context.Background(), docker.containerID, client.ContainerStopOptions{Signal: "SIGTERM"}); err != nil {
		return err
	}
	return docker.Wait()
}

func (docker *DockerContainer) Signal(signal os.Signal) error {
	if docker.containerID == "" {
		return process.ErrNoProcess
	} else if _, err := docker.DockerClient.ContainerStop(context.Background(), docker.containerID, client.ContainerStopOptions{Signal: signal.String()}); err != nil {
		return err
	}
	return nil
}

func (w *DockerContainer) AttachStdin(r io.Reader) error {
	if w.containerID != "" {
		hijackedResponse, err := w.DockerClient.ContainerAttach(context.Background(), w.containerID, client.ContainerAttachOptions{
			Stream: true,
			Stdin:  true,
		})
		if err != nil {
			return err
		}
		go io.Copy(hijackedResponse.Conn, r)
	}
	return process.ErrNoProcess
}
func (w *DockerContainer) AttachStdout(w2 io.Writer) error {
	if w.containerID != "" {
		log, err := w.DockerClient.ContainerLogs(context.Background(), w.containerID, client.ContainerLogsOptions{Follow: true, ShowStdout: true, Tail: "5"})
		if err != nil {
			return err
		}
		go stdcopy.StdCopy(w2, nil, log)
	}
	return process.ErrNoProcess
}
func (w *DockerContainer) AttachStderr(w2 io.Writer) error {
	if w.containerID != "" {
		log, err := w.DockerClient.ContainerLogs(context.Background(), w.containerID, client.ContainerLogsOptions{Follow: true, ShowStderr: true, Tail: "5"})
		if err != nil {
			return err
		}
		go stdcopy.StdCopy(nil, w2, log)
	}
	return process.ErrNoProcess
}

func (docker *DockerContainer) Start(options *process.Exec) error {
	if docker.DockerClient == nil {
		var err error
		if docker.DockerClient, err = client.NewClientWithOpts(client.FromEnv); err != nil {
			return err
		}
	}

	// Return error if container started
	if docker.containerID != "" {
		return process.ErrNoCallStart
	}

	ctx := context.Background()
	dVolumes, dPorts := map[string]struct{}{}, network.PortSet{}
	for _, vol := range docker.Volumes {
		dVolumes[vol] = struct{}{}
	}
	for _, port := range docker.Ports {
		p, err := network.ParsePort(fmt.Sprintf("%s/%s", port.Port(), port.Proto()))
		if err != nil {
			return err
		}
		dPorts[p] = struct{}{}
	}

	config := container.Config{
		AttachStdin:  true,
		AttachStdout: true,
		AttachStderr: true,
		Tty:          true,
		OpenStdin:    true,
		Env:          options.Environment.ToSlice(),
		Cmd:          []string{},
		Entrypoint:   options.Arguments,
		Image:        docker.Image,
		WorkingDir:   options.Cwd,
		Volumes:      dVolumes,
		ExposedPorts: dPorts,
	}

	host := container.HostConfig{
		AutoRemove: true,
		Tmpfs: map[string]string{
			"/tmp": "rw,nosuid",
		},
	}

	containerCreated, err := docker.DockerClient.ContainerCreate(ctx, client.ContainerCreateOptions{
		Config:     &config,
		HostConfig: &host,
		Name:       docker.ContainerName,
	})
	if docker.containerID = containerCreated.ID; err != nil {
		return err
	} else if _, err = docker.DockerClient.ContainerStart(ctx, docker.containerID, client.ContainerStartOptions{}); err != nil {
		return err
	}

	if options.Context != nil {
		ctx := options.Context
		go func() {
			<-ctx.Done()
			docker.Signal(os.Interrupt)
		}()
	}

	return nil
}