Color output controls

BuildKit and Buildx have support for modifying the colors that are used to output information to the terminal. You can set the environment variable BUILDKIT_COLORS to something like run=123,20,245:error=yellow:cancel=blue:warning=white to set the colors that you would like to use:

Setting NO_COLOR to anything will disable any colorized output as recommended by no-color.org:

Note

Parsing errors will be reported but ignored. This will result in default color values being used where needed.

See also the list of pre-defined colors.

Configure BuildKit

If you create a docker-container or kubernetes builder with Buildx, you can apply a custom BuildKit configuration by passing the --config flag to the docker buildx create command.

Registry mirror

You can define a registry mirror to use for your builds. Doing so redirects BuildKit to pull images from a different hostname. The following steps exemplify defining a mirror for docker.io (Docker Hub) to mirror.gcr.io .

1. Create a TOML at /etc/buildkitd.toml with the following content:

   debug = true
   [registry."docker.io"]
     mirrors = ["mirror.gcr.io"]
   

   Note

   debug = true turns on debug requests in the BuildKit daemon, which logs a message that shows when a mirror is being used.

2. Create a docker-container builder that uses this BuildKit configuration:

   $ docker buildx create --use --bootstrap \
     --name mybuilder \
     --driver docker-container \
     --config /etc/buildkitd.toml
   

3. Build an image:

   docker buildx build --load . -f - <<EOF
   FROM alpine
   RUN echo "hello world"
   EOF
   

The BuildKit logs for this builder now shows that it uses the GCR mirror. You can tell by the fact that the response messages include the x-goog-* HTTP headers.

$ docker logs buildx_buildkit_mybuilder0

...
time="2022-02-06T17:47:48Z" level=debug msg="do request" request.header.accept="application/vnd.docker.container.image.v1+json, */*" request.header.user-agent=containerd/1.5.8+unknown request.method=GET spanID=9460e5b6e64cec91 traceID=b162d3040ddf86d6614e79c66a01a577
time="2022-02-06T17:47:48Z" level=debug msg="fetch response received" response.header.accept-ranges=bytes response.header.age=1356 response.header.alt-svc="h3=\":443\"; ma=2592000,h3-29=\":443\"; ma=2592000,h3-Q050=\":443\"; ma=2592000,h3-Q046=\":443\"; ma=2592000,h3-Q043=\":443\"; ma=2592000,quic=\":443\"; ma=2592000; v=\"46,43\"" response.header.cache-control="public, max-age=3600" response.header.content-length=1469 response.header.content-type=application/octet-stream response.header.date="Sun, 06 Feb 2022 17:25:17 GMT" response.header.etag="\"774380abda8f4eae9a149e5d5d3efc83\"" response.header.expires="Sun, 06 Feb 2022 18:25:17 GMT" response.header.last-modified="Wed, 24 Nov 2021 21:07:57 GMT" response.header.server=UploadServer response.header.x-goog-generation=1637788077652182 response.header.x-goog-hash="crc32c=V3DSrg==" response.header.x-goog-hash.1="md5=d0OAq9qPTq6aFJ5dXT78gw==" response.header.x-goog-metageneration=1 response.header.x-goog-storage-class=STANDARD response.header.x-goog-stored-content-encoding=identity response.header.x-goog-stored-content-length=1469 response.header.x-guploader-uploadid=ADPycduqQipVAXc3tzXmTzKQ2gTT6CV736B2J628smtD1iDytEyiYCgvvdD8zz9BT1J1sASUq9pW_ctUyC4B-v2jvhIxnZTlKg response.status="200 OK" spanID=9460e5b6e64cec91 traceID=b162d3040ddf86d6614e79c66a01a577
time="2022-02-06T17:47:48Z" level=debug msg="fetch response received" response.header.accept-ranges=bytes response.header.age=760 response.header.alt-svc="h3=\":443\"; ma=2592000,h3-29=\":443\"; ma=2592000,h3-Q050=\":443\"; ma=2592000,h3-Q046=\":443\"; ma=2592000,h3-Q043=\":443\"; ma=2592000,quic=\":443\"; ma=2592000; v=\"46,43\"" response.header.cache-control="public, max-age=3600" response.header.content-length=1471 response.header.content-type=application/octet-stream response.header.date="Sun, 06 Feb 2022 17:35:13 GMT" response.header.etag="\"35d688bd15327daafcdb4d4395e616a8\"" response.header.expires="Sun, 06 Feb 2022 18:35:13 GMT" response.header.last-modified="Wed, 24 Nov 2021 21:07:12 GMT" response.header.server=UploadServer response.header.x-goog-generation=1637788032100793 response.header.x-goog-hash="crc32c=aWgRjA==" response.header.x-goog-hash.1="md5=NdaIvRUyfar8201DleYWqA==" response.header.x-goog-metageneration=1 response.header.x-goog-storage-class=STANDARD response.header.x-goog-stored-content-encoding=identity response.header.x-goog-stored-content-length=1471 response.header.x-guploader-uploadid=ADPycdtR-gJYwC7yHquIkJWFFG8FovDySvtmRnZBqlO3yVDanBXh_VqKYt400yhuf0XbQ3ZMB9IZV2vlcyHezn_Pu3a1SMMtiw response.status="200 OK" spanID=9460e5b6e64cec91 traceID=b162d3040ddf86d6614e79c66a01a577
time="2022-02-06T17:47:48Z" level=debug msg=fetch spanID=9460e5b6e64cec91 traceID=b162d3040ddf86d6614e79c66a01a577
time="2022-02-06T17:47:48Z" level=debug msg=fetch spanID=9460e5b6e64cec91 traceID=b162d3040ddf86d6614e79c66a01a577
time="2022-02-06T17:47:48Z" level=debug msg=fetch spanID=9460e5b6e64cec91 traceID=b162d3040ddf86d6614e79c66a01a577
time="2022-02-06T17:47:48Z" level=debug msg=fetch spanID=9460e5b6e64cec91 traceID=b162d3040ddf86d6614e79c66a01a577
time="2022-02-06T17:47:48Z" level=debug msg="do request" request.header.accept="application/vnd.docker.image.rootfs.diff.tar.gzip, */*" request.header.user-agent=containerd/1.5.8+unknown request.method=GET spanID=9460e5b6e64cec91 traceID=b162d3040ddf86d6614e79c66a01a577
time="2022-02-06T17:47:48Z" level=debug msg="fetch response received" response.header.accept-ranges=bytes response.header.age=1356 response.header.alt-svc="h3=\":443\"; ma=2592000,h3-29=\":443\"; ma=2592000,h3-Q050=\":443\"; ma=2592000,h3-Q046=\":443\"; ma=2592000,h3-Q043=\":443\"; ma=2592000,quic=\":443\"; ma=2592000; v=\"46,43\"" response.header.cache-control="public, max-age=3600" response.header.content-length=2818413 response.header.content-type=application/octet-stream response.header.date="Sun, 06 Feb 2022 17:25:17 GMT" response.header.etag="\"1d55e7be5a77c4a908ad11bc33ebea1c\"" response.header.expires="Sun, 06 Feb 2022 18:25:17 GMT" response.header.last-modified="Wed, 24 Nov 2021 21:07:06 GMT" response.header.server=UploadServer response.header.x-goog-generation=1637788026431708 response.header.x-goog-hash="crc32c=ZojF+g==" response.header.x-goog-hash.1="md5=HVXnvlp3xKkIrRG8M+vqHA==" response.header.x-goog-metageneration=1 response.header.x-goog-storage-class=STANDARD response.header.x-goog-stored-content-encoding=identity response.header.x-goog-stored-content-length=2818413 response.header.x-guploader-uploadid=ADPycdsebqxiTBJqZ0bv9zBigjFxgQydD2ESZSkKchpE0ILlN9Ibko3C5r4fJTJ4UR9ddp-UBd-2v_4eRpZ8Yo2llW_j4k8WhQ response.status="200 OK" spanID=9460e5b6e64cec91 traceID=b162d3040ddf86d6614e79c66a01a577
...

Setting registry certificates

If you specify registry certificates in the BuildKit configuration, the daemon copies the files into the container under /etc/buildkit/certs . The following steps show adding a self-signed registry certificate to the BuildKit configuration.

1. Add the following configuration to /etc/buildkitd.toml :

   # /etc/buildkitd.toml
   debug = true
   [registry."myregistry.com"]
     ca=["/etc/certs/myregistry.pem"]
     [[registry."myregistry.com".keypair]]
       key="/etc/certs/myregistry_key.pem"
       cert="/etc/certs/myregistry_cert.pem"
   

   This tells the builder to push images to the myregistry.com registry using the certificates in the specified location ( /etc/certs ).

2. Create a docker-container builder that uses this configuration:

   $ docker buildx create --use --bootstrap \
     --name mybuilder \
     --driver docker-container \
     --config /etc/buildkitd.toml
   

3. Inspect the builder’s configuration file ( /etc/buildkit/buildkitd.toml ), it shows that the certificate configuration is now configured in the builder.

   $ docker exec -it buildx_buildkit_mybuilder0 cat /etc/buildkit/buildkitd.toml
   

   debug = true
   
   [registry]
   
     [registry."myregistry.com"]
       ca = ["/etc/buildkit/certs/myregistry.com/myregistry.pem"]
   
       [[registry."myregistry.com".keypair]]
         cert = "/etc/buildkit/certs/myregistry.com/myregistry_cert.pem"
         key = "/etc/buildkit/certs/myregistry.com/myregistry_key.pem"
   

4. Verify that the certificates are inside the container:

   $ docker exec -it buildx_buildkit_mybuilder0 ls /etc/buildkit/certs/myregistry.com/
   myregistry.pem    myregistry_cert.pem   myregistry_key.pem
   

Now you can push to the registry using this builder, and it will authenticate using the certificates:

$ docker buildx build --push --tag myregistry.com/myimage:latest .

CNI networking

CNI networking for builders can be useful for dealing with network port contention during concurrent builds. CNI is not yet available in the default BuildKit image. But you can create your own image that includes CNI support.

The following Dockerfile example shows a custom BuildKit image with CNI support. It uses the CNI config for integration tests in BuildKit as an example. Feel free to include your own CNI configuration.

# syntax=docker/dockerfile:1

ARG BUILDKIT_VERSION=v{{ site.buildkit_version }}
ARG CNI_VERSION=v1.0.1

FROM --platform=$BUILDPLATFORM alpine AS cni-plugins
RUN apk add --no-cache curl
ARG CNI_VERSION
ARG TARGETOS
ARG TARGETARCH
WORKDIR /opt/cni/bin
RUN curl -Ls https://github.com/containernetworking/plugins/releases/download/$CNI_VERSION/cni-plugins-$TARGETOS-$TARGETARCH-$CNI_VERSION.tgz | tar xzv

FROM moby/buildkit:${BUILDKIT_VERSION}
ARG BUILDKIT_VERSION
RUN apk add --no-cache iptables
COPY --from=cni-plugins /opt/cni/bin /opt/cni/bin
ADD https://raw.githubusercontent.com/moby/buildkit/${BUILDKIT_VERSION}/hack/fixtures/cni.json /etc/buildkit/cni.json

Now you can build this image, and create a builder instance from it using the --driver-opt image option:

$ docker buildx build --tag buildkit-cni:local --load .
$ docker buildx create --use --bootstrap \
  --name mybuilder \
  --driver docker-container \
  --driver-opt "image=buildkit-cni:local" \
  --buildkitd-flags "--oci-worker-net=cni"

Resource limiting

Max parallelism

You can limit the parallelism of the BuildKit solver, which is particularly useful for low-powered machines, using a BuildKit configuration while creating a builder with the --config flags.

# /etc/buildkitd.toml
[worker.oci]
  max-parallelism = 4

Now you can create a docker-container builder that will use this BuildKit configuration to limit parallelism.

$ docker buildx create --use \
  --name mybuilder \
  --driver docker-container \
  --config /etc/buildkitd.toml

TCP connection limit

TCP connections are limited to 4 simultaneous connections per registry for pulling and pushing images, plus one additional connection dedicated to metadata requests. This connection limit prevents your build from getting stuck while pulling images. The dedicated metadata connection helps reduce the overall build time.

More information: moby/buildkit#2259

Track deployments

Note

Atomist is currently in Early Access. Features and APIs are subject to change.

By integrating Atomist with a runtime environment, you can track vulnerabilities for deployed containers. This gives you contexts for whether security debt is increasing or decreasing.

There are several options for how you could implement deployment tracking:

• Invoking the API directly
• Adding it as a step in your continuous deployment pipeline
• Creating Kubernetes admission controllers

API

Each Atomist workspace exposes an API endpoint. Submitting a POST request to the endpoint updates Atomist about what image you are running in your environments. This lets you compare data for images you build against images of containers running in staging or production.

You can find the API endpoint URL on the Integrations page. Using this API requires an API key.

The most straight-forward use is to post to this endpoint using a webhook. When deploying a new image, submit an automated POST request (using curl , for example) as part of your deployment pipeline.

$ curl <api-endpoint-url> \\
  -X POST \\
  -H "Content-Type: application/json" \\
  -H "Authorization: Bearer <api-token>" \\
  -d '{"image": {"url": "<image-url>@<sha256-digest>"}}'

Parameters

The API supports the following parameters in the request body:

{
  "image": {
    "url": "string",
    "name": "string"
  },
  "environment": {
    "name": "string"
  },
  "platform": {
    "os": "string",
    "architecture": "string",
    "variant": "string"
  }
}

Integrate with GitHub

Note

Atomist is currently in Early Access. Features and APIs are subject to change.

When installed for a GitHub organization, the Atomist GitHub app links repository activity to images. This enables Atomist to relate image tags and digests directly to specific commits in the source repository. It also opens up the possibility to incorporate image analysis in your Git workflow. For example, by adding analysis checks to pull request, or automatically raising pull requests for updating and pinning base image versions.

Install the GitHub app in the organization that contains the source code repositories for your Docker images.

Connect to GitHub

1. Go to https://dso.docker.com/ and sign in using your Docker ID.
2. Open the Repositories tab.

3. Select Connect to GitHub and follow the authorization flow. This installs the Atomist GitHub App.

   

4. Install the app.

   Note

   If your GitHub account is a member of one or more organizations, GitHub prompts you to choose which account to install the app into. Select the account that contains the source repositories for your images.

   After installing the app, GitHub redirects you back to Atomist.

5. In the repository selection menu, select what repositories you want Atomist to start watching.

   

   If you are just looking to evaluate Atomist, start by selecting a few repositories during evaluation. Once you are comfortable using Atomist, you can switch on the integration for all repositories. Selecting All repositories also includes any repository created in the future.

   Important

   If Atomist detects FROM commands in Dockerfiles in the selected repositories, it begins raising automated pull requests. The pull requests update the Dockerfile FROM -line to specify the image versions (as digests).

6. Select Save selection .

Atomist is now connected with your GitHub repositories and is be able to link image analyses with Git commits.

Manage repository access

If you wish to add or remove repository access for Atomist, go to the Repositories page.

• Select All repositories if you want enable Atomist for all connected organizations and repositories.
• Select Only select repositories if you want to provision access to only a subset of repositories.

Disconnect from GitHub

You might want to disconnect from GitHub when:

• You want to change which GitHub organization or account connected to your Atomist workspace.

  To do so, disconnect the old GitHub organization or account first. Then, follow the instructions for connecting to GitHub for the new GitHub organization or account.

• You want to remove Atomist access to a GitHub organization or account when you no longer use Atomist.

To disconnect a GitHub account:

1. Go to Repositories and select the Disconnect link. This removes the connection to your GitHub organization or account.

2. Go to the GitHub Applications settings page, then:

3. Find atomist on the Installed GitHub Apps tab.

4. Select Configure

5. Select Uninstall . This removes the installation of the Atomist GitHub App from your GitHub organization or account.

6. Find atomist on the Authorized GitHub Apps tab.

7. Select Revoke .

   This removes the authorization of the Atomist GitHub App from your GitHub organization or account.

Docker driver

The Buildx Docker driver is the default driver. It uses the BuildKit server components built directly into the Docker engine. The Docker driver requires no configuration.

Unlike the other drivers, builders using the Docker driver can’t be manually created. They’re only created automatically from the Docker context.

Images built with the Docker driver are automatically loaded to the local image store.

Synopsis

# The Docker driver is used by buildx by default
docker buildx build .

It’s not possible to configure which BuildKit version to use, or to pass any additional BuildKit parameters to a builder using the Docker driver. The BuildKit version and parameters are preset by the Docker engine internally.

If you need additional configuration and flexibility, consider using the Docker container driver.

Further reading

For more information on the Docker driver, see the buildx reference.