Description

This PR implements the Azure Blob Store implementation and closely aligns with the AWS S3 implementation. This utilizes the azure_sdk libraries (azure_core, azure_storage, and azure_storage_blobs). The libraries are still unofficial and being developed, so we should be mindful of any breaking changes in the future.

Apart from that, I started my development by first creating a POC: https://gist.github.com/amankrx/45e7d2a6ed935aa13dda0318681af2ad This POC tests the get and upload blobs with all the default features disabled for Azure SDK. This creates a custom HttpClient with manually signing the requests to perform the transactions.

My current implementation still utilizes the hmac_rust feature enabled for signing the request. Please do let me know if we need any updates here.

The implementations are mostly the same as what we have for Amazon S3. The key difference here is that I have implemented a Custom HTTP Client for executing the requests.

I still have to test it against an actual Blob Storage and implement a testing framework. I have created this PR to get an idea if my current implementation is on the right track.

Regarding the testing framework, I believe we would have to create some custom mocking requests to test the functions. Azure SDK does support the mocking using mock transport(https://github.com/Azure/azure-sdk-for-rust/tree/main/eng/test/mock_transport), but the mocking library isn’t as mature enough as what we have for S3.

Fixes #1542 /claim #1542

Type of change

Please delete options that aren’t relevant.

• New feature (non-breaking change which adds functionality)
• This change requires a documentation update

How Has This Been Tested?

I tested it locally using the bazel test command with the azure_blob_backend_with_local_fast_cas.json5 file, configured to use the actual blob storage. Additionally, I created a test suite to cover both individual happy paths and error scenarios.

Checklist

• Updated documentation if needed
• Tests added/amended
• Local testing completed
• bazel test //... passes locally
• PR is contained in a single commit, using git amend see some docs

This change is