Download Resources from Component Versions

Goal

Download resources from a component version using the OCM CLI. Learn how to fetch specific resources, optionally transform them to their native format, and save them to your local filesystem.

You’ll end up with

  • A resource file downloaded from a component version
  • Optionally a resource transformed to its native format (e.g., Helm chart .tgz)

Estimated time: ~5 minutes

How it works

  flowchart LR
    A[Component Version] -- "ocm download resource" --> B[Resource as Local File]

The OCM CLI fetches a specific resource from a component version and saves it to your local filesystem.

Prerequisites

Download Workflow

  1. List available resources

    First, check which resources are available in the component version. Until the OCM CLI supports resource listing, you can use the ocm get cv command to see the complete component

    ocm get cv ghcr.io/open-component-model//ocm.software/demos/podinfo:6.8.0 -oyaml
    Inspect the component for resources

    The output shows the component version descriptor, including the resources section where you can find the available resources and their identities (e.g., name, version). We’re interested in the chart resource, which is a Helm chart stored as OCI artifact in an OCI registry.

    - component:
    componentReferences: []
    creationTime: "2025-03-18T11:23:20Z"
    name: ocm.software/demos/podinfo
    provider: ocm.software
    repositoryContexts:
      - baseUrl: ghcr.io
        componentNameMapping: urlPath
        subPath: open-component-model
        type: OCIRegistry
    resources:
      - access:
          imageReference: ghcr.io/stefanprodan/podinfo:6.8.0
          type: ociArtifact
        digest:
          hashAlgorithm: SHA-256
          normalisationAlgorithm: ociArtifactDigest/v1
          value: 6c1975b871efb327528c84d46d38e6dd7906eecee6402bc270eeb7f1b1a506df
        name: image
        relation: external
        type: ociImage
        version: 6.8.0
      - access:
          imageReference: ghcr.io/stefanprodan/charts/podinfo:6.8.0
          type: ociArtifact
        digest:
          hashAlgorithm: SHA-256
          normalisationAlgorithm: ociArtifactDigest/v1
          value: 2360bdf32ddc50c05f8e128118173343b0a012a338daf145b16e0da9c80081a4
        name: chart
        relation: external
        type: helmChart
        version: 6.8.0
    sources: []
    version: 6.8.0
  meta:
    schemaVersion: v2
  signatures:
    - digest:
        hashAlgorithm: SHA-256
        normalisationAlgorithm: jsonNormalisation/v3
        value: 76082d5a6398c7f0d62bc614ec7857dc0ceb93e8cf0a36cbdeb963eddad0707f
      name: my-ocm
      signature:
        algorithm: RSASSA-PKCS1-V1_5
        mediaType: application/vnd.ocm.signature.rsa
        value: 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

  2. Download the resource

    Use the ocm download resource command with the --identity flag to specify which resource to download. We download the chart resource, which is a Helm chart:

     ocm download resource ghcr.io/open-component-model//ocm.software/demos/podinfo:6.8.0 \
   --identity name=chart \
    --output helmchart-oci
    You should see this output
    time=2026-03-04T13:32:54.297+01:00 level=INFO msg="resource downloaded successfully" output=helmchart-oci
time=2026-03-04T13:32:55.295+01:00 level=INFO msg=copied descriptor.mediaType=application/vnd.cncf.helm.chart.content.v1.tar+gzip descriptor.digest=sha256:ddf24dfc79800f80a8f1e5b8d462b15619c22d77c8ffe454636fef3b9a6d4f60 descriptor.size=14956
time=2026-03-04T13:32:55.295+01:00 level=INFO msg=copied descriptor.mediaType=application/vnd.cncf.helm.config.v1+json descriptor.digest=sha256:eb2808c21a03a7007ef9a7b5207af0a3b4115be5ce4bb340e0bf501abaf8d31e descriptor.size=348
time=2026-03-04T13:32:55.295+01:00 level=INFO msg=copied descriptor.mediaType=application/vnd.oci.image.manifest.v1+json descriptor.digest=sha256:2360bdf32ddc50c05f8e128118173343b0a012a338daf145b16e0da9c80081a4 descriptor.size=828

  3. Verify the download

    Check that the downloaded resource exists and has content:

    ls -la helmchart-oci
    Inspect the downloaded OCI artifact

    The downloaded Helm chart is in OCI blob format.

    total 8
drwxr-xr-x  5 D032990 160 März  4 13:38 .
drwxrwxrwt 23 root    736 März  4 13:42 ..
drwxr-xr-x  3 D032990  96 März  4 13:38 blobs
-rw-r--r--  1 D032990 282 März  4 13:38 index.json
-rw-r--r--  1 D032990  30 März  4 13:38 oci-layout
    jq . index.json
    {
  "schemaVersion": 2,
  "manifests": [
    {
      "mediaType": "application/vnd.oci.image.manifest.v1+json",
      "digest": "sha256:2360bdf32ddc50c05f8e128118173343b0a012a338daf145b16e0da9c80081a4",
      "size": 828,
      "annotations": {
        "org.opencontainers.image.ref.name": "ghcr.io/stefanprodan/charts/podinfo:6.8.0"
      }
    }
  ]
}

Using Transformers

To download resources in their native format instead of OCI blob format, use the --transformer flag.

In this example, we download the Helm chart resource using the helm transformer, which converts the OCI blob back into a standard Helm chart archive. The Helm chart is downloaded into a directory specified by --output.

ocm download resource ghcr.io/open-component-model//ocm.software/demos/podinfo:6.8.0 \
  --identity name=chart \
  --output helmchart-tgz \
  --transformer helm
You should see this output
time=2026-03-04T13:59:23.279+01:00 level=INFO msg="transforming resource..."
time=2026-03-04T13:59:24.238+01:00 level=INFO msg=copied descriptor.mediaType=application/vnd.cncf.helm.config.v1+json descriptor.digest=sha256:eb2808c21a03a7007ef9a7b5207af0a3b4115be5ce4bb340e0bf501abaf8d31e descriptor.size=348
time=2026-03-04T13:59:24.359+01:00 level=INFO msg=copied descriptor.mediaType=application/vnd.cncf.helm.chart.content.v1.tar+gzip descriptor.digest=sha256:ddf24dfc79800f80a8f1e5b8d462b15619c22d77c8ffe454636fef3b9a6d4f60 descriptor.size=14956
time=2026-03-04T13:59:24.361+01:00 level=INFO msg=copied descriptor.mediaType=application/vnd.oci.image.manifest.v1+json descriptor.digest=sha256:2360bdf32ddc50c05f8e128118173343b0a012a338daf145b16e0da9c80081a4 descriptor.size=828
time=2026-03-04T13:59:24.363+01:00 level=INFO msg="resource transformed successfully"
time=2026-03-04T13:59:24.363+01:00 level=INFO msg="resource downloaded successfully" output=helmchart-tgz
Inspect the Helm chart

The downloaded archive is now a regular Helm chart archive:

tar tvf helmchart-tgz/podinfo-6.8.0.tgz
-rw-r--r-- 0/0             313 2025-03-11 10:31 podinfo/Chart.yaml
-rw-r--r-- 0/0            4351 2025-03-11 10:31 podinfo/values.yaml
-rw-r--r-- 0/0            1361 2025-03-11 10:31 podinfo/templates/NOTES.txt
-rw-r--r-- 0/0            1965 2025-03-11 10:31 podinfo/templates/_helpers.tpl
-rw-r--r-- 0/0             455 2025-03-11 10:31 podinfo/templates/certificate.yaml
-rw-r--r-- 0/0            8051 2025-03-11 10:31 podinfo/templates/deployment.yaml
-rw-r--r-- 0/0             995 2025-03-11 10:31 podinfo/templates/hpa.yaml
-rw-r--r-- 0/0            1154 2025-03-11 10:31 podinfo/templates/ingress.yaml
-rw-r--r-- 0/0            2338 2025-03-11 10:31 podinfo/templates/linkerd.yaml
-rw-r--r-- 0/0             437 2025-03-11 10:31 podinfo/templates/pdb.yaml
-rw-r--r-- 0/0             239 2025-03-11 10:31 podinfo/templates/redis/config.yaml
-rw-r--r-- 0/0            1928 2025-03-11 10:31 podinfo/templates/redis/deployment.yaml
-rw-r--r-- 0/0             369 2025-03-11 10:31 podinfo/templates/redis/service.yaml
-rw-r--r-- 0/0             988 2025-03-11 10:31 podinfo/templates/service.yaml
-rw-r--r-- 0/0             325 2025-03-11 10:31 podinfo/templates/serviceaccount.yaml
-rw-r--r-- 0/0             598 2025-03-11 10:31 podinfo/templates/servicemonitor.yaml
-rw-r--r-- 0/0             912 2025-03-11 10:31 podinfo/templates/tests/cache.yaml
-rw-r--r-- 0/0             607 2025-03-11 10:31 podinfo/templates/tests/fail.yaml
-rw-r--r-- 0/0             694 2025-03-11 10:31 podinfo/templates/tests/grpc.yaml
-rw-r--r-- 0/0             884 2025-03-11 10:31 podinfo/templates/tests/jwt.yaml
-rw-r--r-- 0/0             781 2025-03-11 10:31 podinfo/templates/tests/service.yaml
-rw-r--r-- 0/0             632 2025-03-11 10:31 podinfo/templates/tests/timeout.yaml
-rw-r--r-- 0/0             815 2025-03-11 10:31 podinfo/templates/tests/tls.yaml
-rw-r--r-- 0/0             333 2025-03-11 10:31 podinfo/.helmignore
-rw-r--r-- 0/0           11365 2025-03-11 10:31 podinfo/LICENSE
-rw-r--r-- 0/0           13442 2025-03-11 10:31 podinfo/README.md
-rw-r--r-- 0/0            3427 2025-03-11 10:31 podinfo/values-prod.yaml

Specifying Resource Identity

If multiple resources share the same name, use additional identity attributes:

ocm download resource <repo>//<component>:<version> \
  --identity name=image,version=1.0.0 \
  --output image.tar

CLI Reference

CommandDescription
ocm download resourceDownload a specific resource
ocm get cvGet component versions and resources
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