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

OCM CLI installed
jq installed for JSON parsing (optional)
A component version with resources to download (see Create Component Versions)

Download Workflow

As mentioned in the concept document for Component Identity, components can be stored in OCI registries or local CTF archives, but the way you access them is the same — using their unique identity.

The following examples show component versions stored in a local CTF archive and in a remote OCI registry. The local CTF uses the component created in the Getting Started: Create Component Versions tutorial, while the remote OCI registry uses the Podinfo component published to GitHub Container Registry.

List the 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 version descriptor, including the resources section.

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. 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: OCIImage/v1
        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: OCIImage/v1
        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: 08554a08acd6373e12cd6cea8fc71d6a734a45827fe5ed22900fbb4e3d689dbe0d5178389b8e4939e3e3a6d600fd8f287ca829ba19ddcb0fb7d8364f526651d677a84f75912c4aace8fe93650bfafdf09525bffc256ea0a5b23b47d21ab8ab2b17336c0f7516d4bd8e9aee89de313026be39b5226c31424a51dcafce7a06d5d17ea532a40caff4046beb2f7798892bdf26929b682ee3f1fd65cba3d9b3d0914d84253a6c91190174272bbdb52410f5f8f135d6303bbde6387691b636417111760306354664cb20cf02ed4ce1e31d4d0f27e0309b0a4041c56b7de2e1abe65b564cffe6f6dfe38dc94197ab8e52523b652ac37b4b841a9242ef30c5b3d31098e4

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":"2026-04-10T14:06:57.85304+02:00","level":"INFO","msg":"capabilities sent"}
time=2026-04-10T14:07:01.593+02:00 level=INFO msg="resource downloaded successfully" output=helmchart-oci

Verify the Download

Check that the downloaded resource exists and has content:

ls -la helmchart-oci

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 . helmchart-oci/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"
      }
    }
  ]
}

List available resources

ocm get cv /tmp/helloworld/transport-archive//github.com/acme.org/helloworld:1.0.0 -oyaml

Inspect the component for resources

The output shows the component version descriptor. We’re interested in the mylocalfile resource, which is a plain text file.

- component:
    componentReferences: null
    name: github.com/acme.org/helloworld
    provider: acme.org
    repositoryContexts: null
    resources:
      - access:
          localReference: sha256:70a2577d7b649574cbbba99a2f2ebdf27904a4abf80c9729923ee67ea8d2d9d8
          mediaType: text/plain; charset=utf-8
          type: LocalBlob/v1
        digest:
          hashAlgorithm: SHA-256
          normalisationAlgorithm: genericBlobDigest/v1
          value: 70a2577d7b649574cbbba99a2f2ebdf27904a4abf80c9729923ee67ea8d2d9d8
        name: mylocalfile
        relation: local
        type: blob
        version: 1.0.0
      - access:
          imageReference: ghcr.io/stefanprodan/podinfo:6.11.1@sha256:8fa56908408de98f24aed2a162b1bb42c0b98df7abfcc5a76a14a8be510457c5
          type: OCIImage/v1
        digest:
          hashAlgorithm: SHA-256
          normalisationAlgorithm: genericBlobDigest/v1
          value: 8fa56908408de98f24aed2a162b1bb42c0b98df7abfcc5a76a14a8be510457c5
        name: image
        relation: external
        type: ociImage
        version: 1.0.0
    sources: null
    version: 1.0.0
  meta:
    schemaVersion: v2