Epic Goal

• Exposing the existing available chunksize configuration option the docker registry already supports. [TechPreviewNoUpgrade feature gate]
• Fixing the multipart upload issues with Cloudflare R2 [ https://github.com/distribution/distribution/issues/3873 |https://github.com/distribution/distribution/issues/3873#issuecomment-1900164569]

Why is this important?

• Trying to use Cloudflare R2 as a storage backend. Small images where multipart isn't applied work fine, bigger images fail
• To enable multipart upload with greater chunksize

Scenarios

1. Utilize the R2 cloudfare storage which requires higher chunksize

Acceptance Criteria

• TechPreviewNoUpgrade feature gate option

Dependencies (internal and external)

• None

Previous Work (Optional):

1. https://github.com/openshift/cluster-image-registry-operator/pull/1026
2. https://github.com/openshift/api/pull/1864
3. https://github.com/openshift/api/pull/1877

Tested with:

1. set registry operator unmanaged
2. followed the doc https://docs.openshift.com/container-platform/4.15/registry/configuring_registry_stora[…]e/configuring-registry-storage-aws-user-infrastructure.html
3. added env var to the deployment for chunksize

References::

https://docker-docs.uclv.cu/registry/storage-drivers/s3/

https://docs.aws.amazon.com/AmazonS3/latest/userguide/qfacts.html

https://distribution.github.io/distribution/storage-drivers/s3/

https://docs.aws.amazon.com/AmazonS3/latest/API/sigv4-streaming.html#sigv4-chunked-upload-sig-calculation-chunk0