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crazy-max merged 1 commit into from
Sep 11, 2025
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docs: --load flag clarity #3421

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4 changes: 2 additions & 2 deletions commands/bake.go
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Original file line number Diff line number Diff line change
Expand Up @@ -499,8 +499,8 @@ func bakeCmd(dockerCli command.Cli, rootOpts *rootOptions) *cobra.Command {
flags := cmd.Flags()

flags.StringArrayVarP(&options.files, "file", "f", []string{}, "Build definition file")
flags.BoolVar(&options.exportLoad, "load", false, `Shorthand for "--set=*.output=type=docker"`)
flags.BoolVar(&options.exportPush, "push", false, `Shorthand for "--set=*.output=type=registry"`)
flags.BoolVar(&options.exportLoad, "load", false, `Shorthand for "--set=*.output=type=docker". Conditional.`)
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@aevesdocker aevesdocker Sep 11, 2025

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This was the shortest way I could think of doing it

flags.BoolVar(&options.exportPush, "push", false, `Shorthand for "--set=*.output=type=registry". Conditional.`)
flags.StringVar(&options.sbom, "sbom", "", `Shorthand for "--set=*.attest=type=sbom"`)
flags.StringVar(&options.provenance, "provenance", "", `Shorthand for "--set=*.attest=type=provenance"`)
flags.StringArrayVar(&options.overrides, "set", nil, `Override target value (e.g., "targetpattern.key=value")`)
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53 changes: 51 additions & 2 deletions docs/reference/buildx_bake.md
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Expand Up @@ -22,14 +22,14 @@ Build from a file
| `-D`, `--debug` | `bool` | | Enable debug logging |
| [`-f`](#file), [`--file`](#file) | `stringArray` | | Build definition file |
| [`--list`](#list) | `string` | | List targets or variables |
| `--load` | `bool` | | Shorthand for `--set=*.output=type=docker` |
| [`--load`](#load) | `bool` | | Shorthand for `--set=*.output=type=docker`. Conditional. |
| [`--metadata-file`](#metadata-file) | `string` | | Write build result metadata to a file |
| [`--no-cache`](#no-cache) | `bool` | | Do not use cache when building the image |
| [`--print`](#print) | `bool` | | Print the options without building |
| [`--progress`](#progress) | `string` | `auto` | Set type of progress output (`auto`, `quiet`, `plain`, `tty`, `rawjson`). Use plain to show container output |
| [`--provenance`](#provenance) | `string` | | Shorthand for `--set=*.attest=type=provenance` |
| [`--pull`](#pull) | `bool` | | Always attempt to pull all referenced images |
| `--push` | `bool` | | Shorthand for `--set=*.output=type=registry` |
| [`--push`](#push) | `bool` | | Shorthand for `--set=*.output=type=registry`. Conditional. |
| [`--sbom`](#sbom) | `string` | | Shorthand for `--set=*.attest=type=sbom` |
| [`--set`](#set) | `stringArray` | | Override target value (e.g., `targetpattern.key=value`) |

Expand Down Expand Up @@ -220,6 +220,47 @@ format. Alternatively, you can use a long-form CSV syntax and specify a
$ docker buildx bake --list=type=targets,format=json
```

### <a name="load"></a> Load images into Docker (--load)

The `--load` flag is a convenience shorthand for adding an image export of type
`docker`:

```console
--load ≈ --set=*.output=type=docker
```

However, its behavior is conditional:

- If the build definition has no output defined, `--load` adds
`type=docker`.
- If the build definition’s outputs are `docker`, `image`, `registry`,
`oci`, `--load` will add a `type=docker` export if one is not already present.
- If the build definition contains `local` or `tar` outputs,
`--load` does nothing. It will not override those outputs.

For example, with the following bake file:

```hcl
target "default" {
output = ["type=tar,dest=hi.tar"]
}
```

With `--load`:

```console
$ docker buildx bake --load --print
...
"output": [
{
"dest": "hi.tar"
"type": "tar",
}
]
```

The `tar` output remains unchanged.

### <a name="metadata-file"></a> Write build results metadata to a file (--metadata-file)

Similar to [`buildx build --metadata-file`](buildx_build.md#metadata-file) but
Expand Down Expand Up @@ -339,6 +380,14 @@ Same as [`build --provenance`](buildx_build.md#provenance).

Same as `build --pull`.

### <a name="push"></a> Push images to a registry (--push)

The `--push` flag follows the same logic as `--load`:

- If no outputs are defined, it adds a `type=image,push=true` export.
- For existing `image` outputs, it sets `push=true`.
- If outputs are set to `local` or `tar`, it does not override them.

### <a name="sbom"></a> Create SBOM attestations (--sbom)

Same as [`build --sbom`](buildx_build.md#sbom).
Expand Down