feat: indicate supported platforms when checking a session image

[leafty]

Add a new field platforms returned when checking a session image with GET /api/data/sessions/images. The field may be returned when the image is accessible and will contain the list of supported platforms. If gathering this information fails, the field will simply not be present in the response.

Example:

curl 'https://<hostname>/api/data/sessions/images?image_url=node:24' | jq

{
  "accessible": true,
  "platforms": [
    {
      "architecture": "amd64",
      "os": "linux"
    },
    {
      "architecture": "arm64",
      "os": "linux",
      "variant": "v8"
    },
    {
      "architecture": "ppc64le",
      "os": "linux"
    },
    {
      "architecture": "s390x",
      "os": "linux"
    }
  ]
}

Implementation notes:

• The current code related to handling of OCI images is split between renku_data_services.notebooks.api.classes.image and renku_data_services.notebooks.image_check. This will be consolidated in the future inside a single Python module.
• The new renku_data_services.notebooks.oci may seem redundant at present, but the existing image handling code will be refactored to be contained only in the oci module.

/deploy

[RenkuBot]

You can access the deployment of this PR at https://renku-ci-ds-1101.dev.renku.ch

[coveralls]

Pull Request Test Coverage Report for Build 19145569596

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

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• For a quick fix, rebase this PR at GitHub. Your next report should be accurate.

Details

• 241 of 314 (76.75%) changed or added relevant lines in 12 files are covered.
• 8 unchanged lines in 4 files lost coverage.
• Overall coverage decreased (-0.03%) to 86.819%

---

Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
components/renku_data_services/notebooks/core_sessions.py	1	2	50.0%
components/renku_data_services/notebooks/blueprints.py	8	13	61.54%
components/renku_data_services/notebooks/oci/utils.py	13	46	28.26%
components/renku_data_services/notebooks/image_check.py	8	42	19.05%

Files with Coverage Reduction	New Missed Lines	%
components/renku_data_services/notebooks/image_check.py	1	41.38%
components/renku_data_services/repositories/utils.py	1	90.91%
components/renku_data_services/connected_services/core.py	3	78.38%
components/renku_data_services/crc/core.py	3	77.42%

Totals
Change from base Build 19133192028:	-0.03%
Covered Lines:	23054
Relevant Lines:	26554

---

💛 - Coveralls

[sgaist]

Why not just remove it ? (repeat for the same changes below)

[leafty]

Ah yes, I didn't finish cleaning up the code changes.

[sgaist]

Might be a silly question but why not return only the httpx.Response ? The code must be extracted from it anyway.