build: only show buildkit-specific flags if buildkit is enabled

Signed-off-by: Tibor Vass <tibor@docker.com>
(cherry picked from commit bbd01fe)
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

cli/command/cli.go

@@ -8,6 +8,7 @@ import (
  "os"
  "path/filepath"
  "runtime"
+ "strconv"
  "time"
 
  "github.com/docker/cli/cli"
@@ -133,6 +134,20 @@ func (cli *DockerCli) ContentTrustEnabled() bool {
  return cli.contentTrust
 }
 
+// BuildKitEnabled returns whether buildkit is enabled either through a daemon setting
+// or otherwise the client-side DOCKER_BUILDKIT environment variable
+func BuildKitEnabled(si ServerInfo) (bool, error) {
+ buildkitEnabled := si.BuildkitVersion == types.BuilderBuildKit
+ if buildkitEnv := os.Getenv("DOCKER_BUILDKIT"); buildkitEnv != "" {
+ var err error
+ buildkitEnabled, err = strconv.ParseBool(buildkitEnv)
+ if err != nil {
+ return false, errors.Wrap(err, "DOCKER_BUILDKIT environment variable expects boolean value")
+ }
+ }
+ return buildkitEnabled, nil
+}
+
 // ManifestStore returns a store for local manifests
 func (cli *DockerCli) ManifestStore() manifeststore.Store {
  // TODO: support override default location from config file

cli/command/image/build.go

@@ -13,7 +13,6 @@ import (
  "path/filepath"
  "regexp"
  "runtime"
- "strconv"
  "strings"
 
  "github.com/docker/cli/cli"
@@ -137,6 +136,8 @@ func NewBuildCommand(dockerCli command.Cli) *cobra.Command {
  flags.BoolVar(&options.pull, "pull", false, "Always attempt to pull a newer version of the image")
  flags.StringSliceVar(&options.cacheFrom, "cache-from", []string{}, "Images to consider as cache sources")
  flags.BoolVar(&options.compress, "compress", false, "Compress the build context using gzip")
+ flags.SetAnnotation("compress", "no-buildkit", nil)
+
  flags.StringSliceVar(&options.securityOpt, "security-opt", []string{}, "Security options")
  flags.StringVar(&options.networkMode, "network", "default", "Set the networking mode for the RUN instructions during build")
  flags.SetAnnotation("network", "version", []string{"1.25"})
@@ -154,14 +155,18 @@ func NewBuildCommand(dockerCli command.Cli) *cobra.Command {
  flags.BoolVar(&options.stream, "stream", false, "Stream attaches to server to negotiate build context")
  flags.SetAnnotation("stream", "experimental", nil)
  flags.SetAnnotation("stream", "version", []string{"1.31"})
+ flags.SetAnnotation("stream", "no-buildkit", nil)
 
- flags.StringVar(&options.progress, "progress", "auto", "Set type of progress output (only if BuildKit enabled) (auto, plain, tty). Use plain to show container output")
+ flags.StringVar(&options.progress, "progress", "auto", "Set type of progress output (auto, plain, tty). Use plain to show container output")
+ flags.SetAnnotation("progress", "buildkit", nil)
 
  flags.StringArrayVar(&options.secrets, "secret", []string{}, "Secret file to expose to the build (only if BuildKit enabled): id=mysecret,src=/local/secret")
  flags.SetAnnotation("secret", "version", []string{"1.39"})
+ flags.SetAnnotation("secret", "buildkit", nil)
 
  flags.StringArrayVar(&options.ssh, "ssh", []string{}, "SSH agent socket or keys to expose to the build (only if BuildKit enabled) (format: default|<id>[=<socket>|<key>[,<key>]])")
  flags.SetAnnotation("ssh", "version", []string{"1.39"})
+ flags.SetAnnotation("ssh", "buildkit", nil)
  return cmd
 }
 
@@ -183,22 +188,17 @@ func (out *lastProgressOutput) WriteProgress(prog progress.Progress) error {
 
 // nolint: gocyclo
 func runBuild(dockerCli command.Cli, options buildOptions) error {
- if buildkitEnv := os.Getenv("DOCKER_BUILDKIT"); buildkitEnv != "" {
- enableBuildkit, err := strconv.ParseBool(buildkitEnv)
- if err != nil {
- return errors.Wrap(err, "DOCKER_BUILDKIT environment variable expects boolean value")
- }
- if enableBuildkit {
- return runBuildBuildKit(dockerCli, options)
- }
- } else if dockerCli.ServerInfo().BuildkitVersion == types.BuilderBuildKit {
+ buildkitEnabled, err := command.BuildKitEnabled(dockerCli.ServerInfo())
+ if err != nil {
+ return err
+ }
+ if buildkitEnabled {
  return runBuildBuildKit(dockerCli, options)
  }
 
  var (
  buildCtx io.ReadCloser
  dockerfileCtx io.ReadCloser
- err error
  contextDir string
  tempDir string
  relDockerfile string

cmd/docker/docker.go

@@ -100,8 +100,10 @@ func setHelpFunc(dockerCli *command.DockerCli, cmd *cobra.Command, flags *pflag.
  ccmd.Println(err)
  return
  }
-
- hideUnsupportedFeatures(ccmd, dockerCli)
+ if err := hideUnsupportedFeatures(ccmd, dockerCli); err != nil {
+ ccmd.Println(err)
+ return
+ }
  defaultHelpFunc(ccmd, args)
  })
 }
@@ -235,15 +237,21 @@ func hideFeatureSubCommand(subcmd *cobra.Command, hasFeature bool, annotation st
  }
 }
 
-func hideUnsupportedFeatures(cmd *cobra.Command, details versionDetails) {
+func hideUnsupportedFeatures(cmd *cobra.Command, details versionDetails) error {
  clientVersion := details.Client().ClientVersion()
  osType := details.ServerInfo().OSType
  hasExperimental := details.ServerInfo().HasExperimental
  hasExperimentalCLI := details.ClientInfo().HasExperimental
+ hasBuildKit, err := command.BuildKitEnabled(details.ServerInfo())
+ if err != nil {
+ return err
+ }
 
  cmd.Flags().VisitAll(func(f *pflag.Flag) {
  hideFeatureFlag(f, hasExperimental, "experimental")
  hideFeatureFlag(f, hasExperimentalCLI, "experimentalCLI")
+ hideFeatureFlag(f, hasBuildKit, "buildkit")
+ hideFeatureFlag(f, !hasBuildKit, "no-buildkit")
  // hide flags not supported by the server
  if !isOSTypeSupported(f, osType) || !isVersionSupported(f, clientVersion) {
  f.Hidden = true
@@ -259,6 +267,8 @@ func hideUnsupportedFeatures(cmd *cobra.Command, details versionDetails) {
  for _, subcmd := range cmd.Commands() {
  hideFeatureSubCommand(subcmd, hasExperimental, "experimental")
  hideFeatureSubCommand(subcmd, hasExperimentalCLI, "experimentalCLI")
+ hideFeatureSubCommand(subcmd, hasBuildKit, "buildkit")
+ hideFeatureSubCommand(subcmd, !hasBuildKit, "no-buildkit")
  // hide subcommands not supported by the server
  if subcmdVersion, ok := subcmd.Annotations["version"]; ok && versions.LessThan(clientVersion, subcmdVersion) {
  subcmd.Hidden = true
@@ -267,6 +277,7 @@ func hideUnsupportedFeatures(cmd *cobra.Command, details versionDetails) {
  subcmd.Hidden = true
  }
  }
+ return nil
 }
 
 // Checks if a command or one of its ancestors is in the list
@@ -313,6 +324,7 @@ func areFlagsSupported(cmd *cobra.Command, details versionDetails) error {
  if _, ok := f.Annotations["experimentalCLI"]; ok && !hasExperimentalCLI {
  errs = append(errs, fmt.Sprintf("\"--%s\" is on a Docker cli with experimental cli features enabled", f.Name))
  }
+ // buildkit-specific flags are noop when buildkit is not enabled, so we do not add an error in that case
  }
  })
  if len(errs) > 0 {