history: json format support for inspect command

Signed-off-by: CrazyMax <1951866+crazy-max@users.noreply.github.com>

Author: crazy-max

commands/history/inspect.go

@@ -25,6 +25,7 @@ import (
 	"github.com/docker/buildx/util/confutil"
 	"github.com/docker/buildx/util/desktop"
 	"github.com/docker/cli/cli/command"
+	"github.com/docker/cli/cli/command/formatter"
 	"github.com/docker/cli/cli/debug"
 	slsa "github.com/in-toto/in-toto-golang/in_toto/slsa_provenance/common"
 	slsa02 "github.com/in-toto/in-toto-golang/in_toto/slsa_provenance/v0.2"
@@ -57,6 +58,7 @@ const (
 type inspectOptions struct {
 	builder string
 	ref     string
+	format  string
 }
 
 type inspectOutput struct {
@@ -399,6 +401,14 @@ workers0:
 	})
 	out.Config.RestRaw = unusedAttrs
 
+	if opts.format == formatter.JSONFormatKey {
+		enc := json.NewEncoder(dockerCli.Out())
+		enc.SetIndent("", "  ")
+		return enc.Encode(out)
+	} else if opts.format != formatter.RawFormatKey {
+		return errors.Errorf("unsupported format %q", opts.format)
+	}
+
 	tw := tabwriter.NewWriter(dockerCli.Out(), 1, 8, 1, '\t', 0)
 
 	if out.Context != "" {
@@ -603,7 +613,8 @@ func inspectCmd(dockerCli command.Cli, rootOpts RootOptions) *cobra.Command {
 		attachmentCmd(dockerCli, rootOpts),
 	)
 
-	// flags := cmd.Flags()
+	flags := cmd.Flags()
+	flags.StringVar(&options.format, "format", formatter.RawFormatKey, "Format the output")
 
 	return cmd
 }

docs/reference/buildx_history_inspect.md

@@ -12,11 +12,69 @@ Inspect a build
 
 ### Options
 
-| Name            | Type     | Default | Description                              |
-|:----------------|:---------|:--------|:-----------------------------------------|
-| `--builder`     | `string` |         | Override the configured builder instance |
-| `-D`, `--debug` | `bool`   |         | Enable debug logging                     |
+| Name                  | Type     | Default | Description                              |
+|:----------------------|:---------|:--------|:-----------------------------------------|
+| `--builder`           | `string` |         | Override the configured builder instance |
+| `-D`, `--debug`       | `bool`   |         | Enable debug logging                     |
+| [`--format`](#format) | `string` | `raw`   | Format the output                        |
 
 
 <!---MARKER_GEN_END-->
 
+## Examples
+
+### <a name="format"></a> Format the output (--format)
+
+Output format can be one of `raw`, `json`.
+
+```console
+$ docker buildx history inspect --format raw
+Context:        .
+Dockerfile:     Dockerfile
+VCS Repository: https://github.com/crazy-max/buildx.git
+VCS Revision:   04aab6958cb5feb012a3c607569573b5cab141e1
+Target:         binaries
+Platforms:      linux/amd64
+Keep Git Dir:   true
+
+Started:        2025-02-06 16:15:13
+Duration:       1m  3s
+Build Steps:    16/16 (25% cached)
+
+
+Materials:
+URI                                                             DIGEST
+pkg:docker/docker/dockerfile@1                                  sha256:93bfd3b68c109427185cd78b4779fc82b484b0b7618e36d0f104d4d801e66d25
+pkg:docker/golang@1.23-alpine3.21?platform=linux%2Famd64        sha256:2c49857f2295e89b23b28386e57e018a86620a8fede5003900f2d138ba9c4037
+pkg:docker/tonistiigi/xx@1.6.1?platform=linux%2Famd64           sha256:923441d7c25f1e2eb5789f82d987693c47b8ed987c4ab3b075d6ed2b5d6779a3
+
+Attachments:
+DIGEST                                                                  PLATFORM        TYPE
+sha256:1b44912514074d3e309d80f8a5886a4d89eeeb52bef4d3e57ced17d1781bfce1                 https://slsa.dev/provenance/v0.2
+
+Print build logs: docker buildx history logs qrdbfvaoarfz42ye54lzx9aoy
+```
+
+```console
+$ docker buildx history inspect --format json
+{
+  "name": "buildx (binaries)",
+  "context": ".",
+  "dockerfile": "Dockerfile",
+  "vcs_repository": "https://github.com/crazy-max/buildx.git",
+  "vcs_revision": "04aab6958cb5feb012a3c607569573b5cab141e1",
+  "target": "binaries",
+  "platform": [
+    "linux/amd64"
+  ],
+  "keep_git_dir": true,
+  "started_at": "2025-02-06T16:15:13.077644732+01:00",
+  "complete_at": "2025-02-06T16:16:17.046656296+01:00",
+  "duration": 63969011564,
+  "status": "completed",
+  "num_completed_steps": 16,
+  "num_total_steps": 16,
+  "num_cached_steps": 4,
+  "config": {}
+}
+```