chore: add isManifest function to determine a manifest

[cdrage]

chore: add isManifest function to determine a manifest

What does this PR do?

Adds a guessIsManifest function to try and determine if an image is a
manifest or not:

• By checking the repotags and digests
• Checking labels does not exist, as labels are not added when creating
  a manifest
• VirtualSize is under 1MB as a manifest list is just text that points
  to other images

We are unable to check the history (manifest commonly has no history) as
Dockerode API does not support getting the history of the image.

Screenshot / video of UI

N/A

What issues does this PR fix or reference?

Closes #6690

How to test this PR?

• Tests are covering the bug fix or the new feature

Signed-off-by: Charlie Drage charlie@charliedrage.com

[cdrage]

Switching to draft for two things:

• Check that the engine is podman
• Check history is blank

You are right @benoitf with docker.io/hello-world it would be considered a manifest due to the small size:

  {
    "Id": "ee301c921b8aadc002973b2e0c3da17d701dcd994b606769a7e6eaa100b81d44",
    "ParentId": "",
    "RepoTags": [
      "docker.io/library/hello-world:latest"
    ],
    "RepoDigests": [
      "docker.io/library/hello-world@sha256:2d4e459f4ecb5329407ae3e47cbc107a2fbace221354ca75960af4c047b3cb13",
      "docker.io/library/hello-world@sha256:53641cd209a4fecfc68e21a99871ce8c6920b2e7502df0a20671c6fccc73a7c6"
    ],
    "Created": 1683046167,
    "Size": 23301,
    "SharedSize": 0,
    "VirtualSize": 23301,
    "Labels": null,
    "Containers": 0,
    "Names": [
      "docker.io/library/hello-world:latest"
    ],
    "Digest": "sha256:53641cd209a4fecfc68e21a99871ce8c6920b2e7502df0a20671c6fccc73a7c6",
    "History": [
      "docker.io/library/hello-world:latest"
    ]
  }

So we have to make sure history is blank / does not exist as well.

[cdrage]

Updated and ready for review.

Requires #6713 before merging.

• Switched to 50KB max for the manifest size
• Updated tests
• Check for null / empty history
• Check engine name matches to 'podman'

[cdrage]

TODO:

• Add test for the following output and making sure it's "not a manifest":

  {
    "Id": "ee301c921b8aadc002973b2e0c3da17d701dcd994b606769a7e6eaa100b81d44",
    "ParentId": "",
    "RepoTags": [
      "docker.io/library/hello-world:latest"
    ],
    "RepoDigests": [
      "docker.io/library/hello-world@sha256:2d4e459f4ecb5329407ae3e47cbc107a2fbace221354ca75960af4c047b3cb13",
      "docker.io/library/hello-world@sha256:53641cd209a4fecfc68e21a99871ce8c6920b2e7502df0a20671c6fccc73a7c6"
    ],
    "Created": 1683046167,
    "Size": 23301,
    "SharedSize": 0,
    "VirtualSize": 23301,
    "Labels": null,
    "Containers": 0,
    "Names": [
      "docker.io/library/hello-world:latest"
    ],
    "Digest": "sha256:53641cd209a4fecfc68e21a99871ce8c6920b2e7502df0a20671c6fccc73a7c6",
    "History": [
      "docker.io/library/hello-world:latest"
    ]
  }

[cdrage]

Ready for another review, test has been added 💯

[benoitf]

still approving