# Docker Manifests

GoReleaser can also create and push Docker multi-platform images using the
`docker manifest` tool.

For it to work, it needs to be enabled in the
[client's configuration](https://github.com/docker/cli/blob/master/experimental/README.md).

Please make sure `docker manifest` works before opening issues.

Notice that if you have something in the `docker_manifests` section in your
config file, GoReleaser will add the manifest's to the release notes instead of
the Docker images names.

!!! warning

    Notice that the images used in the manifest **need to be pushed** for this
    to work. This is a limitation of how `docker manifest create` works. For
    more info, check
    [this issue](https://github.com/goreleaser/goreleaser/issues/2606).

## Customization

You can create several manifests in a single GoReleaser run, here are all the
options available:

```yaml title=".goreleaser.yaml"
docker_manifests:
  # You can have multiple Docker manifests.
  - # ID of the manifest, needed if you want to filter by it later on (e.g. on
    # custom publishers).
    id: myimg

    # Name for the manifest.
    #
    # Templates: allowed.
    name_template: "foo/bar:{{ .Version }}"

    # Image name to be added to this manifest.
    #
    # Templates: allowed.
    image_templates:
      - "foo/bar:{{ .Version }}-amd64"
      - "foo/bar:{{ .Version }}-arm64v8"

    # Extra flags to be passed down to the manifest create command.
    create_flags:
      - --insecure

    # Extra flags to be passed down to the manifest push command.
    push_flags:
      - --insecure

    # Skips the Docker manifest.
    # If you set this to `false` or `auto` on your source Docker configuration,
    #  you'll probably want to do the same here.
    #
    # If set to `auto`, the manifest will not be created in case there is an
    #  indicator of a prerelease in the tag, e.g. v1.0.0-rc1.
    #
    # Templates: allowed.
    skip_push: false

    # Set the "backend" for the Docker manifest pipe.
    # Valid options are: docker, podman
    #
    # Relevant notes:
    # 1. podman is a GoReleaser Pro feature and is only available on Linux;
    # 2. if you set podman here, the respective docker configuration need to use
    #     podman too.
    #
    # Default: 'docker'.
    use: docker
```

<!-- md:templates -->

## How it works

We basically build and push our images as usual, but we also add a new
section to our configuration defining, which images are part of which manifests.

GoReleaser will create and publish the manifest in its publishing phase.

!!! warning

    Unfortunately, the manifest tool needs the images to be pushed to create
    the manifest, that's why we both create and push it in the publishing phase.

## Example config

In this example we will use Docker's `--platform` option to specify the target platform.
This way we can use the same `Dockerfile` for both the `amd64`, and the `arm64`
images (and possibly others):

```dockerfile
# Dockerfile
FROM alpine
ENTRYPOINT ["/usr/bin/mybin"]
COPY mybin /usr/bin/mybin
```

Then, on our GoReleaser configuration file, we need to define both the
`dockers`, and the `docker_manifests` section:

```yaml title=".goreleaser.yaml"
builds:
  - env:
      - CGO_ENABLED=0
    binary: mybin
    goos:
      - linux
    goarch:
      - amd64
      - arm64
dockers:
  - image_templates:
      - "foo/bar:{{ .Version }}-amd64"
    use: buildx
    dockerfile: Dockerfile
    build_flag_templates:
      - "--platform=linux/amd64"
  - image_templates:
      - "foo/bar:{{ .Version }}-arm64v8"
    use: buildx
    goarch: arm64
    dockerfile: Dockerfile
    build_flag_templates:
      - "--platform=linux/arm64/v8"
docker_manifests:
  - name_template: "foo/bar:{{ .Version }}"
    image_templates:
      - "foo/bar:{{ .Version }}-amd64"
      - "foo/bar:{{ .Version }}-arm64v8"
```

!!! warning

    Notice that `--platform` needs to be in the Docker platform format, not Go's.

That config will build the 2 Docker images defined, as well as the manifest,
and push everything to Docker Hub.

## Using Podman

<!-- md:pro -->

You can use [`podman`](https://podman.io) instead of `docker` by setting `use`
to `podman` on your configuration:

```yaml title=".goreleaser.yaml"
docker_manifests:
  - name_template: "foo/bar:{{ .Version }}"
    image_templates:
      - "foo/bar:{{ .Version }}-amd64"
      - "foo/bar:{{ .Version }}-arm64v8"
    use: podman
```

Note that GoReleaser will not install Podman for you, nor change any of its
configuration.