Add first draft of model registry kserve custom storage initializer

[lampajr]

Fixes #24

Description

Provide a first draft of a possible Model Registry (KServe) Custom Storage Initializer based on https://github.com/lampajr/model-registry-storage-initializer PoC

TODOs:

• Write README with development information
• Write separate GET_STARTED guide
• Add image build directive in the model registry root Makefile (re-using csi Makefile)
• Set container image registry
• Add some testing focusing on the MR interaction using testcontainers (mocking the download itself)

Possible improvements (for further iterations)

• Use kiota to autogenerate the client, this will make the CSI less dependent on the internal model registry implementation (this will also make the CSI just tied to the openapi spec rather than MR version)

How Has This Been Tested?

Merge criteria:

• The commits and have meaningful messages; the author will squash them after approval or will ask to merge with squash.
• Testing instructions have been added in the PR body (for PRs involving changes that are not immediately obvious).
• The developer has manually tested the changes and verified that the changes work

[tarilabs]

thank you for sharing this draft @lampajr !

The way I would recommend to move forward is:

• if you are progressing, you can keep draft
• if someone is volunteering for the TODOs, it is worth it to merge it so easier to work on the git repo with

(if that volunteer is you reading this message, drop a comment below so we can coordinate!)

[lampajr]

thank you for sharing this draft @lampajr !

The way I would recommend to move forward is:

• if you are progressing, you can keep draft
• if someone is volunteering for the TODOs, it is worth it to merge it so easier to work on the git repo with

(if that volunteer is you reading this message, drop a comment below so we can coordinate!)

I agree with you, I could work on these two points:

• Write README with development information
• Write separate GET_STARTED guide

Such that there are enough information to try it (at least locally) then I think this PR could be considered as ready as it would be a good starting point.

All other TODOs I think could be done in followup PRs.

Wdyt?

[lampajr]

As discussed, marking this as ready for review.

• Write README with development information ✔️
• Write separate GET_STARTED guide ✔️

The following TODOs can be done in a separate/followup PR

• Add image build directive in the model registry root Makefile (re-using csi Makefile)
• Set container image registry
• Add some testing focusing on the MR interaction using testcontainers (mocking the download itself)

[tarilabs]

beyond minor/nit comment, I'd go ahead and merge this, as it provides already an helpful and pragmatic example of how other KF components/add-ons (in this case KServe) could integrate with Model Registry

[tarilabs]

With reference to conversations in this PR, I'd go ahead and merge this, as it provides already an helpful and pragmatic example of how other KF components/add-ons (in this case KServe) could integrate with Model Registry

/approve
/lgtm

[google-oss-prow]

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