OCPBUGS-83492: Allow :ref suffix in additionalLayerStores path for stargz-store to support lazy image pulling

[BhargaviGudi]

Summary

• Allow :ref suffix in additionalLayerStores path to support lazy image pulling with stargz-store.
• Fixes: https://issues.redhat.com/browse/OCPBUGS-83492

Problem

• ContainerRuntimeConfig API validation rejects the :ref suffix in additionalLayerStores paths, preventing proper configuration of stargz-store for lazy pulling functionality.

• The path /var/lib/stargz-store/store:ref is required for stargz-store to work with CRI-O's additionalLayerStores mechanism, as documented in the upstream stargz-snapshotter installation guide.

  Current behavior:

  $ oc apply -f containerruntimeconfig-with-ref-suffix.yaml                                                                                                                                                         
  Error from server (Invalid): ContainerRuntimeConfig.machineconfiguration.openshift.io "additional-layer-stores" is invalid:                                                                                       
  spec.containerRuntimeConfig.additionalLayerStores[0].path: Invalid value: "/var/lib/stargz-store/store:ref":                                                                                                      
  path must be absolute and contain only alphanumeric characters, '/', '.', '_', and '-'                                                                                                                            
                                                                                                                                                                                                                    

Testing confirmed:

• Without :ref: Lazy pulling does NOT work - images are pulled normally through CRI-O
• With :ref: Lazy pulling works - layers are lazy-fetched through stargz-store, pods reuse cached snapshots

Solution

• Introduced a new LayerStorePath type specifically for additionalLayerStores that allows paths ending with the :ref suffix, while keeping the existing StorePath type unchanged for additionalImageStores and additionalArtifactStores.

Changes:

• Add LayerStorePath type with validation regex: ^/[a-zA-Z0-9/._-]+(:ref)?$
• Update AdditionalLayerStore to use LayerStorePath instead of StorePath
• Add test cases for :ref suffix validation (allow valid :ref, reject other suffixes like :other)
• Update CRD manifests and swagger documentation

Testing
Test cases added to verify:

1. Path with :ref suffix: /var/lib/stargz-store/store:ref
2. Mixed paths (with and without :ref)
3. Invalid suffix: /var/lib/stargz-store:other (must be exactly :ref)

[openshift-ci]

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[openshift-ci]

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[openshift-ci-robot]

@BhargaviGudi: This pull request references Jira Issue OCPBUGS-83492, which is invalid:

• expected the bug to target the "5.0.0" version, but no target version was set

Comment /jira refresh to re-evaluate validity if changes to the Jira bug are made, or edit the title of this pull request to link to a different bug.

The bug has been updated to refer to the pull request using the external bug tracker.

Details

In response to this:

Summary

• Allow :ref suffix in additionalLayerStores path to support lazy image pulling with stargz-store.
• Fixes: https://issues.redhat.com/browse/OCPBUGS-83492

Problem

• ContainerRuntimeConfig API validation rejects the :ref suffix in additionalLayerStores paths, preventing proper configuration of stargz-store for lazy pulling functionality.
• The path /var/lib/stargz-store/store:ref is required for stargz-store to work with CRI-O's additionalLayerStores mechanism, as documented in the upstream stargz-snapshotter installation guide.

Current behavior:

$ oc apply -f containerruntimeconfig-with-ref-suffix.yaml                                                                                                                                                         
Error from server (Invalid): ContainerRuntimeConfig.machineconfiguration.openshift.io "additional-layer-stores" is invalid:                                                                                       
spec.containerRuntimeConfig.additionalLayerStores[0].path: Invalid value: "/var/lib/stargz-store/store:ref":                                                                                                      
path must be absolute and contain only alphanumeric characters, '/', '.', '_', and '-'                                                                                                                            
                                                                                                                                                                                                                  
Testing confirmed:                                                                                                                                                                                                
- Without :ref: Lazy pulling does NOT work - images are pulled normally through CRI-O                                                                                                                             
- With :ref: Lazy pulling works - layers are lazy-fetched through stargz-store, pods reuse cached snapshots

Solution
- Introduced a new LayerStorePath type specifically for additionalLayerStores that allows paths ending with the :ref suffix, while keeping the existing StorePath type unchanged for additionalImageStores and additionalArtifactStores.
                                                                                                                                                                                                                  
Changes:                                                                                                                                                                                                          
- Add LayerStorePath type with validation regex: ^/[a-zA-Z0-9/._-]+(:ref)?$
- Update AdditionalLayerStore to use LayerStorePath instead of StorePath                                                                                                                                          
- Add test cases for :ref suffix validation (allow valid :ref, reject other suffixes like :other)
- Update CRD manifests and swagger documentation                                                                                                                                                                  
                                                                                                                                                                                                                  
Testing
Test cases added to verify:
1. Path with :ref suffix: /var/lib/stargz-store/store:ref
2. Mixed paths (with and without :ref)                                                                                                                                                                         
3. Invalid suffix: /var/lib/stargz-store:other (must be exactly :ref)

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Reviewing files that changed from the base of the PR and between 9abf08e and 590dfad.

⛔ Files ignored due to path filters (6)

• machineconfiguration/v1/zz_generated.crd-manifests/0000_80_machine-config_01_containerruntimeconfigs-CustomNoUpgrade.crd.yaml is excluded by !**/zz_generated.crd-manifests/*
• machineconfiguration/v1/zz_generated.crd-manifests/0000_80_machine-config_01_containerruntimeconfigs-DevPreviewNoUpgrade.crd.yaml is excluded by !**/zz_generated.crd-manifests/*
• machineconfiguration/v1/zz_generated.crd-manifests/0000_80_machine-config_01_containerruntimeconfigs-TechPreviewNoUpgrade.crd.yaml is excluded by !**/zz_generated.crd-manifests/*
• machineconfiguration/v1/zz_generated.featuregated-crd-manifests/containerruntimeconfigs.machineconfiguration.openshift.io/AdditionalStorageConfig.yaml is excluded by !**/zz_generated.featuregated-crd-manifests/**
• machineconfiguration/v1/zz_generated.swagger_doc_generated.go is excluded by !**/zz_generated*
• openapi/openapi.json is excluded by !openapi/**

📒 Files selected for processing (5)

• machineconfiguration/v1/tests/containerruntimeconfigs.machineconfiguration.openshift.io/AdditionalStorageConfig.yaml
• machineconfiguration/v1/types.go
• payload-manifests/crds/0000_80_machine-config_01_containerruntimeconfigs-CustomNoUpgrade.crd.yaml
• payload-manifests/crds/0000_80_machine-config_01_containerruntimeconfigs-DevPreviewNoUpgrade.crd.yaml
• payload-manifests/crds/0000_80_machine-config_01_containerruntimeconfigs-TechPreviewNoUpgrade.crd.yaml

🚧 Files skipped from review as they are similar to previous changes (3)

• payload-manifests/crds/0000_80_machine-config_01_containerruntimeconfigs-DevPreviewNoUpgrade.crd.yaml
• payload-manifests/crds/0000_80_machine-config_01_containerruntimeconfigs-TechPreviewNoUpgrade.crd.yaml
• payload-manifests/crds/0000_80_machine-config_01_containerruntimeconfigs-CustomNoUpgrade.crd.yaml

---

📝 Walkthrough

Walkthrough

Introduces a new Go type LayerStorePath and updates AdditionalLayerStore.Path to use it. The type enforces an absolute path (1–256 chars) composed of letters, digits, / . _ -, disallows consecutive //, and permits an optional trailing :ref. CRD OpenAPI/CEL validations in three manifest files were updated to allow the :ref suffix via the regex ^/[a-zA-Z0-9/._-]+(:ref)?$. Unit tests were added for positive :ref cases, mixed lists, and a negative case rejecting non-:ref suffixes.

🚥 Pre-merge checks | ✅ 9 | ❌ 1

❌ Failed checks (1 inconclusive)

Check name	Status	Explanation	Resolution
Test Structure And Quality	❓ Inconclusive	Test files referenced in PR summary are not accessible in the current repository environment, preventing comprehensive quality assessment.	Provide access to the actual test files (machineconfiguration/v1/tests/*.yaml and any Go test code) to assess test quality against single responsibility, setup/cleanup patterns, timeouts, assertions, and codebase consistency.

✅ Passed checks (9 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title accurately and concisely summarizes the main change: allowing a :ref suffix in additionalLayerStores paths for stargz-store lazy image pulling, with the associated bug number.
Description check	✅ Passed	The description is directly related to the changeset, providing clear context about the problem, solution, implementation details, and testing approach for allowing :ref suffix in additionalLayerStores paths.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Stable And Deterministic Test Names	✅ Passed	All test names in AdditionalStorageConfig.yaml are stable and deterministic with clear descriptive names that remain unchanged across test runs. No dynamic values like timestamps, UUIDs, or random components are present in test names.
Microshift Test Compatibility	✅ Passed	No Ginkgo e2e tests are added in this PR; changes are limited to YAML test cases and Go type definitions.
Single Node Openshift (Sno) Test Compatibility	✅ Passed	PR adds only API type definitions, CRD schema validation rules, and declarative YAML-based schema validation tests with no Ginkgo e2e tests.
Topology-Aware Scheduling Compatibility	✅ Passed	PR changes limited to API type definitions and CRD validation schema rules with no topology-aware scheduling concerns introduced.
Ote Binary Stdout Contract	✅ Passed	PR contains only YAML test cases, CRD manifests, and type definitions with no stdout-writing process-level code modifications.
Ipv6 And Disconnected Network Test Compatibility	✅ Passed	This pull request does not add any new Ginkgo e2e tests. Changes consist of API type definitions, CRD manifests, and YAML-based validation tests only.

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[openshift-ci]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by:
Once this PR has been reviewed and has the lgtm label, please assign everettraven for approval. For more information see the Code Review Process.

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[BhargaviGudi]

/jira refresh

[openshift-ci-robot]

@BhargaviGudi: This pull request references Jira Issue OCPBUGS-83492, which is invalid:

• expected the bug to target either version "5.0." or "openshift-5.0.", but it targets "4.22.0" instead

Comment /jira refresh to re-evaluate validity if changes to the Jira bug are made, or edit the title of this pull request to link to a different bug.

Details

In response to this:

/jira refresh

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the openshift-eng/jira-lifecycle-plugin repository.

[coderabbitai]

Actionable comments posted: 1

🤖 Prompt for all review comments with AI agents

Verify each finding against the current code and only fix it if needed.

Inline comments:
In
`@machineconfiguration/v1/tests/containerruntimeconfigs.machineconfiguration.openshift.io/AdditionalStorageConfig.yaml`:
- Around line 103-114: Update the outdated expectedError strings in the
ContainerRuntimeConfig test cases that assert additionalLayerStores validation:
find the test entries referencing additionalLayerStores (look for the initial
YAML blocks under ContainerRuntimeConfig and the existing expectedError values)
and change the older message fragments ("path must be absolute and contain only
alphanumeric characters, '/', '.', '_', and '-'") to the new message including
the optional ':ref' wording ("path must be absolute and contain only
alphanumeric characters, '/', '.', '_', '-', and optionally end with ':ref'") so
they match LayerStorePath's current error output.

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Fix all unresolved CodeRabbit comments on this PR:

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---

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Run ID: 5825084f-d1fd-4ab7-a6a1-9bff27fa4b7d

📥 Commits

Reviewing files that changed from the base of the PR and between 464776f and 942df24.

⛔ Files ignored due to path filters (5)

• machineconfiguration/v1/zz_generated.crd-manifests/0000_80_machine-config_01_containerruntimeconfigs-CustomNoUpgrade.crd.yaml is excluded by !**/zz_generated.crd-manifests/*
• machineconfiguration/v1/zz_generated.crd-manifests/0000_80_machine-config_01_containerruntimeconfigs-DevPreviewNoUpgrade.crd.yaml is excluded by !**/zz_generated.crd-manifests/*
• machineconfiguration/v1/zz_generated.crd-manifests/0000_80_machine-config_01_containerruntimeconfigs-TechPreviewNoUpgrade.crd.yaml is excluded by !**/zz_generated.crd-manifests/*
• machineconfiguration/v1/zz_generated.featuregated-crd-manifests/containerruntimeconfigs.machineconfiguration.openshift.io/AdditionalStorageConfig.yaml is excluded by !**/zz_generated.featuregated-crd-manifests/**
• machineconfiguration/v1/zz_generated.swagger_doc_generated.go is excluded by !**/zz_generated*

📒 Files selected for processing (5)

• machineconfiguration/v1/tests/containerruntimeconfigs.machineconfiguration.openshift.io/AdditionalStorageConfig.yaml
• machineconfiguration/v1/types.go
• payload-manifests/crds/0000_80_machine-config_01_containerruntimeconfigs-CustomNoUpgrade.crd.yaml
• payload-manifests/crds/0000_80_machine-config_01_containerruntimeconfigs-DevPreviewNoUpgrade.crd.yaml
• payload-manifests/crds/0000_80_machine-config_01_containerruntimeconfigs-TechPreviewNoUpgrade.crd.yaml

[BhargaviGudi]

/jira refresh

[openshift-ci-robot]

@BhargaviGudi: This pull request references Jira Issue OCPBUGS-83492, which is valid. The bug has been moved to the POST state.

3 validation(s) were run on this bug

• bug is open, matching expected state (open)
• bug target version (5.0.0) matches configured target version for branch (5.0.0)
• bug is in the state New, which is one of the valid states (NEW, ASSIGNED, POST)

No GitHub users were found matching the public email listed for the QA contact in Jira (bgudi@redhat.com), skipping review request.

Details

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/jira refresh

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[BhargaviGudi]

/test all

[BhargaviGudi]

/retest-required

[everettraven]

Aside from a small nit to make the godoc and the generated documentation read a bit better, this LGTM.

[openshift-ci]

@BhargaviGudi: all tests passed!

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