docker_image_field_values = apply_overrides(
            image_ref,
            overrides,
            {
                "dependencies": [spec_file_address.spec],
                "instructions": [f"FROM {image_ref}"],
                "repository": image_ref.image,
                "tags": ["docker-mirror"],
            },
        )

        # Only set `image_tags` if it where not provided with the `overrides`.
        docker_image_field_values.setdefault("image_tags", [image_ref.tag or "latest"])

        yield DockerImageTarget(
            docker_image_field_values,
            address.create_generated(image_ref.target_name),
            union_membership,
        )


@rule
async def generate_targets_from_docker_mirror_images(
    request: GenerateTargetsFromDockerMirrorImages,
    union_membership: UnionMembership,
) -> GeneratedTargets:
    sources = await Get(
        SourceFiles,
        SourceFilesRequest([request.generator[MirrorImagesSourcesField]]),
    )
    contents = await Get(DigestContents, Digest, sources.snapshot.digest)

    gen = partial(generate_targets, request=request, union_membership=union_membership)
    targets = chain(*[gen(c.path, c.content.decode().split("\n")) for c in contents])
    return GeneratedTargets(request.generator, targets)