drone-docker-buildx/plugin/impl.go

package plugin

import (
	"encoding/json"
	"fmt"
	"os"
	"path/filepath"
	"time"

	"github.com/sirupsen/logrus"
	"github.com/urfave/cli/v2"
	"golang.org/x/sys/execabs"
)

// Daemon defines Docker daemon parameters.
type Daemon struct {
	Registry       string          // Docker registry
	Mirror         string          // Docker registry mirror
	Insecure       bool            // Docker daemon enable insecure registries
	StorageDriver  string          // Docker daemon storage driver
	StoragePath    string          // Docker daemon storage path
	Disabled       bool            // DOcker daemon is disabled (already running)
	Debug          bool            // Docker daemon started in debug mode
	Bip            string          // Docker daemon network bridge IP address
	DNS            cli.StringSlice // Docker daemon dns server
	DNSSearch      cli.StringSlice // Docker daemon dns search domain
	MTU            string          // Docker daemon mtu setting
	IPv6           bool            // Docker daemon IPv6 networking
	Experimental   bool            // Docker daemon enable experimental mode
	BuildkitConfig string          // Docker buildkit config
}

// Login defines Docker login parameters.
type Login struct {
	RegistryData
	Config        string
	Registries    []RegistryData
	RegistriesRaw string
}

type RegistryData struct {
	Registry string // Docker registry address
	Username string // Docker registry username
	Password string // Docker registry password
	Email    string // Docker registry email
}

// Build defines Docker build parameters.
type Build struct {
	Ref          string          // Git commit ref
	Branch       string          // Git repository branch
	Dockerfile   string          // Docker build Dockerfile
	Context      string          // Docker build context
	TagsAuto     bool            // Docker build auto tag
	TagsSuffix   string          // Docker build tags with suffix
	Tags         cli.StringSlice // Docker build tags
	ExtraTags    cli.StringSlice // Docker build tags including registry
	Platforms    cli.StringSlice // Docker build target platforms
	Args         cli.StringSlice // Docker build args
	ArgsEnv      cli.StringSlice // Docker build args from env
	Target       string          // Docker build target
	Pull         bool            // Docker build pull
	CacheFrom    []string        // Docker build cache-from
	CacheTo      string          // Docker build cache-to
	Compress     bool            // Docker build compress
	Repo         cli.StringSlice // Docker build repositories
	NoCache      bool            // Docker build no-cache
	AddHost      cli.StringSlice // Docker build add-host
	Quiet        bool            // Docker build quiet
	Output       string          // Docker build output folder
	NamedContext cli.StringSlice // Docker build named context
	Labels       cli.StringSlice // Docker build labels
	Provenance   string          // Docker build provenance attestation
	SBOM         string          // Docker build sbom attestation
	Secrets      []string        // Docker build secrets
}

// Settings for the Plugin.
type Settings struct {
	Daemon Daemon
	Login  Login
	Build  Build
	Dryrun bool
}

const (
	strictFilePerm  = 0o600
	DefaultRegistry = "https://index.docker.io/v1/"
)

// Validate handles the settings validation of the plugin.
func (p *Plugin) Validate() error {
	p.settings.Build.Branch = p.pipeline.Repo.Branch
	p.settings.Build.Ref = p.pipeline.Commit.Ref
	p.settings.Daemon.Registry = p.settings.Login.Registry

	if p.settings.Build.TagsAuto {
		// return true if tag event or default branch
		if UseDefaultTag(
			p.settings.Build.Ref,
			p.settings.Build.Branch,
		) {
			tag, err := DefaultTagSuffix(
				p.settings.Build.Ref,
				p.settings.Build.TagsSuffix,
			)
			if err != nil {
				logrus.Infof("cannot generate tags from %s, invalid semantic version", p.settings.Build.Ref)

				return err
			}

			p.settings.Build.Tags = *cli.NewStringSlice(tag...)
		} else {
			logrus.Infof("skip auto-tagging for %s, not on default branch or tag", p.settings.Build.Ref)

			return nil
		}
	}

	if err := json.Unmarshal([]byte(p.settings.Login.RegistriesRaw), &p.settings.Login.Registries); err != nil {
		return fmt.Errorf("error unmarshal registries: %w", err)
	}

	for i, registryData := range p.settings.Login.Registries {
		if registryData.Registry == "" {
			p.settings.Login.Registries[i].Registry = DefaultRegistry
		}
	}

	return nil
}

// Execute provides the implementation of the plugin.
//
//nolint:gocognit
func (p *Plugin) Execute() error {
	// start the Docker daemon server
	//nolint: nestif
	if !p.settings.Daemon.Disabled {
		// If no custom DNS value set start internal DNS server
		if len(p.settings.Daemon.DNS.Value()) == 0 {
			ip, err := getContainerIP()
			if err != nil {
				logrus.Warnf("error detecting IP address: %v", err)
			}

			if ip != "" {
				logrus.Debugf("discovered IP address: %v", ip)
				p.startCoredns()

				if err := p.settings.Daemon.DNS.Set(ip); err != nil {
					return fmt.Errorf("error setting daemon dns: %w", err)
				}
			}
		}

		p.startDaemon()
	}

	// poll the docker daemon until it is started. This ensures the daemon is
	// ready to accept connections before we proceed.
	for i := 0; i < 15; i++ {
		cmd := commandInfo()

		err := cmd.Run()
		if err == nil {
			break
		}

		time.Sleep(time.Second * 1)
	}

	// Create Auth Config File
	if p.settings.Login.Config != "" {
		if err := os.MkdirAll(dockerHome, strictFilePerm); err != nil {
			return fmt.Errorf("failed to create docker home: %w", err)
		}

		path := filepath.Join(dockerHome, "config.json")

		err := os.WriteFile(path, []byte(p.settings.Login.Config), strictFilePerm)
		if err != nil {
			return fmt.Errorf("error writing config.json: %w", err)
		}
	}

	// login to the Docker registry
	if p.settings.Login.Password != "" {
		cmd := commandLogin(p.settings.Login.RegistryData)

		err := cmd.Run()
		if err != nil {
			return fmt.Errorf("error authenticating: %w", err)
		}
	}

	for _, registryData := range p.settings.Login.Registries {
		cmd := commandLogin(registryData)

		err := cmd.Run()
		if err != nil {
			return fmt.Errorf("error authenticating: %w", err)
		}
	}

	if p.settings.Daemon.BuildkitConfig != "" {
		err := os.WriteFile(buildkitConfig, []byte(p.settings.Daemon.BuildkitConfig), strictFilePerm)
		if err != nil {
			return fmt.Errorf("error writing buildkit.toml: %w", err)
		}
	}

	switch {
	case p.settings.Login.Password != "":
		logrus.Info("Detected registry credentials")
	case len(p.settings.Login.Registries) > 0:
		logrus.Info("Detected multiple registry credentials")
	case p.settings.Login.Config != "":
		logrus.Info("Detected registry credentials file")
	default:
		logrus.Info("Registry credentials or Docker config not provided. Guest mode enabled.")
	}

	// add proxy build args
	addProxyBuildArgs(&p.settings.Build)

	var cmds []*execabs.Cmd
	cmds = append(cmds, commandVersion()) // docker version
	cmds = append(cmds, commandInfo())    // docker info
	cmds = append(cmds, commandBuilder(p.settings.Daemon))
	cmds = append(cmds, commandBuildx())

	cmds = append(cmds, commandBuild(p.settings.Build, p.settings.Dryrun)) // docker build

	// execute all commands in batch mode.
	for _, cmd := range cmds {
		cmd.Stdout = os.Stdout
		cmd.Stderr = os.Stderr
		trace(cmd)

		err := cmd.Run()
		if err != nil {
			return err
		}
	}

	return nil
}