[RFC] Cloud Controller Blobstore Type: storage-cli

Author: stephanme

toc/rfc/rfc-draft-cc-blobstore-storage-cli.md

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+# Meta
+[meta]: #meta
+- Name: Cloud Controller Blobstore Type: storage-cli
+- Start Date: 2025-07-18
+- Author(s): @johha, @stephanme
+- Status: Draft <!-- Acceptable values: Draft, Approved, On Hold, Superseded -->
+- RFC Pull Request: [community #1253](https://github.com/cloudfoundry/community/pull/1253)
+
+
+## Summary
+
+Add a new blobstore type `storage-cli` to the Cloud controller that is based on the Bosh storage CLIs. Long-term, the `storage-cli` blobstore type shall replace the blobstore type `fog`.
+The RFC also proposes to create a new "Storage CLI" area in the Foundational Infrastructure WG to allow cooperation of Bosh and CAPI teams and to consolidate the Bosh storage CLIs in one repository for easier code reuse.
+
+## Problem
+
+Cloud Controller uses the fog gem family to interface with the blobstores of different IaaS providers like Azure, AWS, GCP, and Alibaba Cloud.
+These Ruby gems are largely unmaintained, introducing risks such as:
+* Dependency on deprecated SDKs (e.g. Azure SDK for Ruby has reached EOL)
+* Blocking Ruby version upgrades
+* Potential for unpatched CVEs
+
+## Proposal
+
+Bosh faced similar issues, as it is also written in Ruby and interacts with blobstores. To address this, Bosh introduced standalone CLI tools which shell out from Ruby to handle all blobstore operations:
+- https://github.com/cloudfoundry/bosh-azure-storage-cli
+- https://github.com/cloudfoundry/bosh-s3cli
+- https://github.com/cloudfoundry/bosh-gcscli
+- https://github.com/cloudfoundry/bosh-ali-storage-cli
+
+These storage CLIs are implemented in Go and use the respective provider golang SDKs that are well supported for the foreseeable future.
+
+Cloud Controller shall implement a new blobstore type `storage-cli` that uses the mentioned storage CLIs for blobstore operations. Missing functionality needed by the Cloud Controller shall be added to the storage CLIs in a compatible way:
+- missing commands such as `copy`, `list`, `properties`, `ensure-bucket-exists`
+- missing configuration parameters such as GCP Uniform Bucket Access and timeout parameters
+
+It shall be possible to switch from blobstore type `fog` to type `storage-cli` in a productive Cloud Foundry installation. Once blobstore type `storage-cli` supports all four mentioned IaaS providers, the blobstore type `fog` can be removed from Cloud Controller.
+
+### Storage CLI 
+
+A new area "Storage CLI" shall be added to the Foundational Infrastructure WG in order to allow cooperation of Bosh and CAPI teams:
+
+- create a new "Storage CLI" area
+- add existing approvers of areas "VM deployment lifecycle (BOSH)" (FI) and "CAPI" (ARI) as initial approvers to this new area
+- create a new repository `storage-cli` in this area with the goal to consolidate all existing bosh storage CLIs here
+- copy one existing bosh storage cli into this new repository as starting point (most likely [bosh-azure-storage-cli](https://github.com/cloudfoundry/bosh-azure-storage-cli))
+- setup CI, implement missing commands and configuration parameters
+- continue with the remaining bosh storage CLIs
+
+### Bosh
+
+- switch from bosh storage cli to new `storage-cli` 
+- eventually archive the old bosh storage CLI repos
+
+### Cloud Controller
+
+- add a new blobstore type `storage-cli` that shells out to `storage-cli` for blobstore operations
+- validate functionality with CATS
+- benchmark blobstore operation performance and compare with blobstore type `fog`, enhance performance tests where necessary
+- eventually deprecate and remove the blobstore type `fog` once all IaaS providers are covered
+
+### cf-deployment
+
+- add experimental ops files per IaaS provider for using the `storage-cli` blobstore type
+- eventually promote those ops files and replace the existing fog-based blobstore ops files
+
+## Additional Information
+
+- [cloud_controller_ng #4443](https://github.com/cloudfoundry/cloud_controller_ng/pull/4443) - ADR: Use Bosh Storage CLIs for Blobstore Operations