[Bug]: unknown media-type

[vojtad]

zot version

v2.1.1

Describe the bug

We are using Zot Registry to host our private Docker registry used mainly in our CI. We build images using Docker Buildx with --cache-from and --cache-to parameters set to registry.

Docker Buildx pull and push build cache from/to the registry and it breaks the UI. When I try to open an image with cache in registry it doesn't open because the request fails with the same error you can see in the logs below.

Zot Regsitry also logs these lines in a loop:

zot        | {"level":"warn","mediatype":"application/vnd.oci.image.layer.v1.tar+gzip","goroutine":667,"caller":"zotregistry.dev/zot/pkg/storage/common/common.go:520","time":"2024-10-15T19:00:19.649733557Z","message":"unknown media-type"}
zot        | {"level":"warn","mediatype":"application/vnd.oci.image.layer.v1.tar+gzip","goroutine":667,"caller":"zotregistry.dev/zot/pkg/storage/common/common.go:520","time":"2024-10-15T19:00:19.649817397Z","message":"unknown media-type"}
zot        | {"level":"warn","mediatype":"application/vnd.oci.image.layer.v1.tar+gzip","goroutine":667,"caller":"zotregistry.dev/zot/pkg/storage/common/common.go:520","time":"2024-10-15T19:00:19.649900038Z","message":"unknown media-type"}
zot        | {"level":"warn","mediatype":"application/vnd.buildkit.cacheconfig.v0","goroutine":667,"caller":"zotregistry.dev/zot/pkg/storage/common/common.go:520","time":"2024-10-15T19:00:19.650578642Z","message":"unknown media-type"}

Seems like these media types are not part of the OCI spec but the spec also doesn't forbid them. Is there anything that can be done in Zot Registry to allow Docker Buildx cache to work without issues described above? Are you open to solving these issues?

Here are some discussions about Docker Buildx cache manifests:
moby/buildkit#2220
docker/buildx#173
opencontainers/distribution-spec#290

To reproduce

1. Configuration
   Installed Docker with Docker Buildx

2. Client tool used
   Docker Buildx with --cache-from=type=registry,ref=$CI_REGISTRY_IMAGE_CACHE_TAG and --cache-to=type=registry,ref=$CI_REGISTRY_IMAGE_CACHE_TAG,mode=max

3. Seen error: Described above in the log output.

Expected behavior

I would expect registry to allow these cache images. To show them in UI and to not repeat log lines described above.

Screenshots

No response

Additional context

No response