This topic explains how you can use Dockerfile-based builds with Supply Chain Choreographer.
For source-based supply chains, when you specify the dockerfile
parameter in a workload, the builds switch from using Kpack to using kaniko. Source-based supply chains are supply chains that don’t take a pre-built image. kaniko is an open-source tool for building container images from a Dockerfile without running Docker inside a container.
Parameter name | Description | Example |
---|---|---|
dockerfile |
The relative path to the Dockerfile file in the build context. | ./Dockerfile |
docker_build_context |
The relative path to the directory where the build context is. | . |
docker_build_extra_args |
The list of flags to pass directly to kaniko, such as providing arguments to a build. | - --build-arg=MY_KEY=MY_VALUE |
To build a container image from the github.com/my-foo/bar
repository where the Dockerfile resides in the root of that repository, you can switch from using Kpack to building from that Dockerfile by passing the dockerfile
parameter:
$ tanzu apps workload create my-foo \
--git-repo https://github.com/my-foo/bar \
--git-branch dev \
--label app.kubernetes.io/part-of=foo \
--param dockerfile=./Dockerfile \
--type web
🔎 Create workload:
1 + |---
2 + |apiVersion: carto.run/v1alpha1
3 + |kind: Workload
4 + |metadata:
5 + | labels:
6 + | apps.tanzu.vmware.com/workload-type: web
7 + | name: my-foo
8 + | namespace: dev
9 + |spec:
10 + | params:
11 + | - name: dockerfile
12 + | value: ./Dockerfile
13 + | source:
14 + | git:
15 + | ref:
16 + | branch: dev
17 + | url: https://github.com/my-foo/bar
If the context to be used for the build must be set to a different directory within the repository, use the docker_build_context
parameter to change that:
$ tanzu apps workload create my-foo \
--git-repo https://github.com/my-foo/bar \
--git-branch dev \
--param dockerfile=MyDockerfile \
--param docker_build_context=./src
ImportantThis feature has no platform operator configurations to be passed through the
tap-values.yaml
file, but ifootb-supply-chain-*.registry.ca_cert_data
orshared.ca_cert_data
is configured intap-values
, the certificates are considered when pushing the container image.
kaniko can perform container image builds without a Docker daemon or privileged containers. It does require the use of:
To overcome the limitations imposed by the default unprivileged SCC, Tanzu Application Platform installs:
SecurityContextConstraints/ootb-templates-kaniko-restricted-v2-with-anyuid
with enough extra privileges for kaniko to operate.ClusterRole/ootb-templates-kaniko-restricted-v2-with-anyuid
to permit the use of SCC to any actor binding to that cluster role.Each developer namespace needs a role binding that binds the role to an actor: ServiceAccount
. For example:
apiVersion: rbac.authorization.k8s.io/v1
kind: RoleBinding
metadata:
name: workload-kaniko-scc
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: ClusterRole
name: ootb-templates-kaniko-restricted-v2-with-anyuid
subjects:
- kind: ServiceAccount
name: default
With the SCC created and the ServiceAccount bound to the role that permits the use of the SCC, OpenShift accepts the pods created to run kaniko to build the container images.
For more information, see Set up developer namespaces to use your installed packages.
For more information about SCC, see the Openshift documentation.
Tanzu Kubernetes Grid v1.26 and later clusters with the Pod Security admission feature enabled and set to enforce
cannot run kaniko without configuration changes. This is because the webhook requires containers to run as a non-root user and kaniko needs to run as a root user. This kaniko limitation relates to how image builds are run.
To workaround this limitation, label the namespace that kaniko runs as privileged
. For example:
pod-security.kubernetes.io/enforce: privileged
For more information about this kaniko limitation, see the kaniko documentation.
For more information about the Pod Security admission feature, see the Kubernetes documentation.