[BUG] Capitalization has changed when BlobTraits are serialized into request URI parameters for List Blob requests

Describe the bug I’m a bit unsure whether this should actually be classified as a bug, or whether the behavior is acceptable.

Basically, I’ve noticed that after upgrading from Azure.Storage.Blobs 12.8.4 -> 12.9.1, the URI parameters that are generated when calling BlobContainerClient.GetBlobsAsync() and specifying some traits (such as BlobTraits.Metadata) are capitalized differently than before the upgrade.

Specifically, doing something like:

AsyncPageable<BlobItem> asyncPageable = containerClient.GetBlobsAsync(BlobTraits.Metadata);
IAsyncEnumerator<BlobItem> enumerator = asyncPageable.GetAsyncEnumerator();

and then iterating the enumerator will generate List Blob requests. In version 12.8.4, the request URI would look something like https://<server>/<account>/<container>?restype=container&comp=list&include=metadata, whereas in version 12.9.1 the request URI looks like https://<server>/<account>/<container>?restype=container&comp=list&include=Metadata (notice the capital M in Metadata).

Again, I’m not sure if this is a big deal, but the difference made some of my integration tests fail, because I’m mocking the Azure Storage REST API and did a case-sensitive string comparision (the official api docs does not mention anything about how capitalization is handled, although I suspect that the implementation might be permissive enough to handle this difference?).

I thought I would report it nonetheless, in case this change was not intentional.

Expected behavior GetBlobsAsync(BlobTraits.Metadata) should generate request URIs containing include=metadata as query parameter.

Actual behavior (include Exception or Stack Trace) GetBlobsAsync(BlobTraits.Metadata) generates request URIs containing include=Metadata as query parameter.

Environment:

• Name and version of the Library package used: Azure.Storage.Blobs 12.9.1

[amishra-dev]

URLs are supposed to be case-insensitive, can I safely assume that you are not hindered by it but just wanted to let us know?

[seanmcc-msft]

@egraff, query parameters values are case-insensitive in Azure Storage.