buildinfo.md

Build information

Warning

Build information is deprecated and will be removed in the next release. See the Deprecated features page for status and alternative recommendation about this feature.

Build information structures are generated with build metadata that allows you to see all the sources (images, git repositories) that were used by the build with their exact versions and also the configuration that was passed to the build. This information is also embedded into the image configuration if one is generated.

Build dependencies

Build dependencies are generated when your image has been built. These dependencies include versions of used images, git repositories and HTTP URLs used by LLB Source operation as well as build request attributes.

The structure is base64 encoded and has the following format when decoded:

{
  "frontend": "dockerfile.v0",
  "attrs": {
    "build-arg:foo": "bar",
    "context": "https://github.com/crazy-max/buildkit-buildsources-test.git#master",
    "filename": "Dockerfile",
    "platform": "linux/amd64,linux/arm64",
    "source": "crazymax/dockerfile:master"
  },
  "sources": [
    {
      "type": "docker-image",
      "ref": "docker.io/docker/buildx-bin:0.6.1@sha256:a652ced4a4141977c7daaed0a074dcd9844a78d7d2615465b12f433ae6dd29f0",
      "pin": "sha256:a652ced4a4141977c7daaed0a074dcd9844a78d7d2615465b12f433ae6dd29f0"
    },
    {
      "type": "docker-image",
      "ref": "docker.io/library/alpine:3.13",
      "pin": "sha256:1d30d1ba3cb90962067e9b29491fbd56997979d54376f23f01448b5c5cd8b462"
    },
    {
      "type": "git",
      "ref": "https://github.com/crazy-max/buildkit-buildsources-test.git#master",
      "pin": "259a5aa5aa5bb3562d12cc631fe399f4788642c1"
    },
    {
      "type": "http",
      "ref": "https://raw.githubusercontent.com/moby/moby/v20.10.21/README.md",
      "pin": "sha256:419455202b0ef97e480d7f8199b26a721a417818bc0e2d106975f74323f25e6c"
    }
  ]
}

• frontend defines the frontend used to build.
• attrs defines build request attributes.
• sources defines build sources.
  • type defines the source type (docker-image, git or http).
  • ref is the reference of the source.
  • pin is the source digest.
• deps defines build dependencies of input contexts.

Image config

A new field similar to the one for inline cache has been added to the image configuration to embed build dependencies:

{
  "moby.buildkit.buildinfo.v0": "<base64>"
}

By default, the build dependencies are inlined in the image configuration. You can disable this behavior with the buildinfo attribute.

Exporter response (metadata)

The solver response (ExporterResponse) also contains a new key containerimage.buildinfo with the same structure as image config encoded in base64:

{
  "ExporterResponse": {
    "containerimage.buildinfo": "<base64>",
    "containerimage.digest": "sha256:..."
  }
}

If multi-platforms are specified, they will be suffixed with the corresponding platform:

{
  "ExporterResponse": {
    "containerimage.buildinfo/linux/amd64": "<base64>",
    "containerimage.buildinfo/linux/arm64": "<base64>",
    "containerimage.digest": "sha256:..."
  }
}

Metadata JSON output

If you're using the --metadata-file flag with buildctl, buildx build or buildx bake:

jq '.' metadata.json

{
  "containerimage.buildinfo": {
    "frontend": "dockerfile.v0",
    "attrs": {
      "context": "https://github.com/crazy-max/buildkit-buildsources-test.git#master",
      "filename": "Dockerfile",
      "source": "docker/dockerfile:master"
    },
    "sources": [
      {
        "type": "docker-image",
        "ref": "docker.io/docker/buildx-bin:0.6.1@sha256:a652ced4a4141977c7daaed0a074dcd9844a78d7d2615465b12f433ae6dd29f0",
        "pin": "sha256:a652ced4a4141977c7daaed0a074dcd9844a78d7d2615465b12f433ae6dd29f0"
      },
      {
        "type": "docker-image",
        "ref": "docker.io/library/alpine:3.13",
        "pin": "sha256:026f721af4cf2843e07bba648e158fb35ecc876d822130633cc49f707f0fc88c"
      }
    ]
  },
  "containerimage.digest": "sha256:..."
}