Migrate off of Data injections

This guide explains how to migrate your Zarf deployment from the data injections feature to OCI image-based data delivery methods. Data injections is planned to be deprecated the current Zarf schema version and fully removed by Zarf v1.0.0. There are for several reasons behind this:

• Poor User Experience: Many users have struggled to figure out how to adopt data injections.
• Host dependency: Data injections shells out to tar. This makes testing difficult and introduces differences across environments.
• Better alternatives: OCI images provide a Kubernetes native solution for data delivery, and neatly fit into the Zarf delivery paradigm.

Migration guide

Step 1: Package Your Data in an OCI Image

First, create a container image containing your data:

FROM alpine:3.18
COPY your-data-file /your-data/your-data-file

Build and push this image:

docker build -t your-registry/your-data:tag .
docker push your-registry/your-data:tag

Some registries will not accept images over a certain size. In this case, you can load the image from the Docker Daemon. This can be slow, users are recommended to try out this strategy for improving the speed of image loads. Additionally, before Data Injections is removed Zarf will allow users to load images directly from a tar file, (#2181), this will be significantly faster than Docker daemon pulls.

Step 2: Update zarf.yaml

Before (Data Injections):

kind: ZarfPackageConfig
metadata:
  name: my-data-app

components:
  - name: my-app
    required: true
    images:
      - ghcr.io/my-app:1.0.0
      - alpine:3.18
    dataInjections:
      - source: my-folder
        target:
          namespace: my-app
          selector: app=my-app
          container: data-loader
          path: /data
        compress: true

After (Init Container Strategy):

kind: ZarfPackageConfig
metadata:
  name: init-data-loading

components:
  - name: my-app
    required: true
    images:
      - ghcr.io/my-app:1.0.0
      - your-registry/your-data:tag  # Your container with your data file

Key Changes:

• Remove dataInjections section entirely.
• Replace the image used during data injections with your data image.

Step 3: Update Deployment Manifest

Before (Data Injections):

spec:
  template:
    spec:
      initContainers:
        - name: data-loader
          image: alpine:3.18
          command: ["sh", "-c"]
          args:
            - 'while [ ! -f /data/###ZARF_DATA_INJECTION_MARKER### ]; do echo "waiting for zarf data sync" && sleep 1; done; echo "we are done waiting!"'
          volumeMounts:
            - mountPath: /data
              name: data

After (Init Container Strategy):

spec:
  template:
    spec:
      initContainers:
        - name: data-puller
          image: your-registry/your-data:tag
          command: ["sh", "-c"]
          args:
            - |
              cp /your-data/your-data-file /data/my-app-data-location
              ls -la /data
              echo "Data initialization complete"
          volumeMounts:
            - mountPath: /data
              name: data

Key Changes:

• Replace data injection marker waiting logic with direct data copying.
• Use your data container image.

Your app should be ready to deploy. If there are any reasons that this method does not work for you, please comment in issue #3926

Future Alternatives

Once the new Kubernetes feature OCI volume sources is considered stable, this document will recommend that method. OCI volumes sources, in beta as of Kubernetes 1.33, provide a simpler way to mount data from an image into a pod.