Add metadata-file flag

Signed-off-by: CrazyMax <crazy-max@users.noreply.github.com>

bake/bake.go

@@ -317,6 +317,8 @@ func (c Config) newOverrides(v []string) (map[string]*Target, error) {
 					return nil, errors.Errorf("invalid value %s for boolean key pull", parts[1])
 				}
 				t.Pull = &pull
+			case "metadata-file":
+				continue
 			default:
 				return nil, errors.Errorf("unknown key: %s", keys[1])
 			}

build/build.go

@@ -65,7 +65,6 @@ type Options struct {
 	CacheTo   []client.CacheOptionsEntry
 
 	Allow []entitlements.Entitlement
-	// DockerTarget
 }
 
 type Inputs struct {
@@ -336,7 +335,7 @@ func toSolveOpt(ctx context.Context, d driver.Driver, multiDriver bool, opt Opti
 		}
 	}()
 
-	if opt.ImageIDFile != "" {
+	if len(opt.ImageIDFile) > 0 {
 		// Avoid leaving a stale file if we eventually fail
 		if err := os.Remove(opt.ImageIDFile); err != nil && !os.IsNotExist(err) {
 			return nil, nil, errors.Wrap(err, "removing image ID file")
@@ -449,7 +448,7 @@ func toSolveOpt(ctx context.Context, d driver.Driver, multiDriver bool, opt Opti
 
 	// set up exporters
 	for i, e := range opt.Exports {
-		if (e.Type == "local" || e.Type == "tar") && opt.ImageIDFile != "" {
+		if (e.Type == "local" || e.Type == "tar") && len(opt.ImageIDFile) > 0 {
 			return nil, nil, errors.Errorf("local and tar exporters are incompatible with image ID file")
 		}
 		if e.Type == "oci" && !d.Features()[driver.OCIExporter] {
@@ -656,8 +655,9 @@ func Build(ctx context.Context, drivers []DriverInfo, opt map[string]Options, do
 				respMu.Lock()
 				resp[k] = res[0]
 				respMu.Unlock()
+
 				if len(res) == 1 {
-					if opt.ImageIDFile != "" {
+					if len(opt.ImageIDFile) > 0 {
 						return ioutil.WriteFile(opt.ImageIDFile, []byte(res[0].ExporterResponse["containerimage.digest"]), 0644)
 					}
 					return nil
@@ -687,7 +687,7 @@ func Build(ctx context.Context, drivers []DriverInfo, opt map[string]Options, do
 							if err != nil {
 								return err
 							}
-							if opt.ImageIDFile != "" {
+							if len(opt.ImageIDFile) > 0 {
 								return ioutil.WriteFile(opt.ImageIDFile, []byte(desc.Digest), 0644)
 							}
 

commands/bake.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"encoding/json"
 	"fmt"
+	"io/ioutil"
 	"os"
 
 	"github.com/docker/buildx/bake"
@@ -53,6 +54,9 @@ func runBake(dockerCli command.Cli, targets []string, in bakeOptions) (err error
 	if in.pull != nil {
 		overrides = append(overrides, fmt.Sprintf("*.pull=%t", *in.pull))
 	}
+	if len(in.metadataFile) > 0 {
+		overrides = append(overrides, fmt.Sprintf("*.metadata-file=%s", in.metadataFile))
+	}
 	contextPathHash, _ := os.Getwd()
 
 	ctx2, cancel := context.WithCancel(context.TODO())
@@ -90,7 +94,7 @@ func runBake(dockerCli command.Cli, targets []string, in bakeOptions) (err error
 	}
 
 	if in.printOnly {
-		dt, err := json.MarshalIndent(map[string]map[string]*bake.Target{"target": m}, "", "   ")
+		dt, err := json.MarshalIndent(map[string]map[string]*bake.Target{"target": m}, "", "  ")
 		if err != nil {
 			return err
 		}
@@ -108,7 +112,28 @@ func runBake(dockerCli command.Cli, targets []string, in bakeOptions) (err error
 		return err
 	}
 
-	_, err = build.Build(ctx, dis, bo, dockerAPI(dockerCli), dockerCli.ConfigFile(), printer)
+	resp, err := build.Build(ctx, dis, bo, dockerAPI(dockerCli), dockerCli.ConfigFile(), printer)
+	if err != nil {
+		return err
+	}
+
+	if len(in.metadataFile) > 0 && resp != nil {
+		if err := os.Remove(in.metadataFile); err != nil && !os.IsNotExist(err) {
+			return errors.Wrap(err, "removing metadata file")
+		}
+		mdata := map[string]map[string]string{}
+		for k, r := range resp {
+			mdata[k] = r.ExporterResponse
+		}
+		mdatab, err := json.MarshalIndent(mdata, "", "  ")
+		if err != nil {
+			return err
+		}
+		if err := ioutil.WriteFile(in.metadataFile, mdatab, 0644); err != nil {
+			return err
+		}
+	}
+
 	return err
 }
 

commands/build.go

@@ -2,6 +2,8 @@ package commands
 
 import (
 	"context"
+	"encoding/json"
+	"io/ioutil"
 	"os"
 	"path/filepath"
 	"strings"
@@ -64,10 +66,11 @@ type buildOptions struct {
 }
 
 type commonOptions struct {
-	builder  string
-	noCache  *bool
-	progress string
-	pull     *bool
+	builder      string
+	noCache      *bool
+	progress     string
+	pull         *bool
+	metadataFile string
 	// golangci-lint#826
 	// nolint:structcheck
 	exportPush bool
@@ -200,10 +203,10 @@ func runBuild(dockerCli command.Cli, in buildOptions) error {
 		contextPathHash = in.contextPath
 	}
 
-	return buildTargets(ctx, dockerCli, map[string]build.Options{"default": opts}, in.progress, contextPathHash, in.builder)
+	return buildTargets(ctx, dockerCli, map[string]build.Options{"default": opts}, in.progress, contextPathHash, in.builder, in.metadataFile)
 }
 
-func buildTargets(ctx context.Context, dockerCli command.Cli, opts map[string]build.Options, progressMode, contextPathHash, instance string) error {
+func buildTargets(ctx context.Context, dockerCli command.Cli, opts map[string]build.Options, progressMode, contextPathHash, instance string, metadataFile string) error {
 	dis, err := getInstanceOrDefault(ctx, dockerCli, instance, contextPathHash)
 	if err != nil {
 		return err
@@ -213,11 +216,28 @@ func buildTargets(ctx context.Context, dockerCli command.Cli, opts map[string]bu
 	defer cancel()
 	printer := progress.NewPrinter(ctx2, os.Stderr, progressMode)
 
-	_, err = build.Build(ctx, dis, opts, dockerAPI(dockerCli), dockerCli.ConfigFile(), printer)
+	resp, err := build.Build(ctx, dis, opts, dockerAPI(dockerCli), dockerCli.ConfigFile(), printer)
 	err1 := printer.Wait()
 	if err == nil {
 		err = err1
 	}
+	if err != nil {
+		return err
+	}
+
+	if len(metadataFile) > 0 && resp != nil {
+		// Avoid leaving a stale file if we eventually fail
+		if err := os.Remove(metadataFile); err != nil && !os.IsNotExist(err) {
+			return errors.Wrap(err, "removing metadata file")
+		}
+		mdatab, err := json.MarshalIndent(resp["default"].ExporterResponse, "", "  ")
+		if err != nil {
+			return err
+		}
+		if err := ioutil.WriteFile(metadataFile, mdatab, 0644); err != nil {
+			return err
+		}
+	}
 
 	return err
 }
@@ -333,6 +353,7 @@ func commonBuildFlags(options *commonOptions, flags *pflag.FlagSet) {
 	flags.StringVar(&options.progress, "progress", defaultProgress, "Set type of progress output (auto, plain, tty). Use plain to show container output")
 
 	options.pull = flags.Bool("pull", false, "Always attempt to pull a newer version of the image")
+	flags.StringVar(&options.metadataFile, "metadata-file", "", "Write build result metadata")
 }
 
 func listToMap(values []string, defaultEnv bool) map[string]string {

docs/reference/buildx_bake.md

@@ -18,6 +18,7 @@ Build from a file
 | `--builder string` | Override the configured builder instance |
 | [`-f`](#file), [`--file stringArray`](#file) | Build definition file |
 | `--load` | Shorthand for --set=*.output=type=docker |
+| `--metadata-file string` | Write build result metadata |
 | [`--no-cache`](#no-cache) | Do not use cache when building the image |
 | [`--print`](#print) | Print the options without building |
 | [`--progress string`](#progress) | Set type of progress output (auto, plain, tty). Use plain to show container output |

docs/reference/buildx_build.md

@@ -25,6 +25,7 @@ Start a build
 | `--iidfile string` | Write the image ID to the file |
 | `--label stringArray` | Set metadata for an image |
 | [`--load`](#load) | Shorthand for --output=type=docker |
+| `--metadata-file string` | Write build result metadata |
 | `--network string` | Set the networking mode for the RUN instructions during build |
 | `--no-cache` | Do not use cache when building the image |
 | [`-o`](#output), [`--output stringArray`](#output) | Output destination (format: type=local,dest=path) |