Resource warning: Sending a large body directly with raw bytes might lock the event loop

[curia-damiano]

The Python SDK for BlobStorage throws the following warning: "Resource warning: Sending a large body directly with raw bytes might lock the event loop"

I am using the latest version of Python and the latest version of the blob storage sdk.

** Steps to reproduce**
async with BlobServiceClient(account_url=accountUrl, credential=accountKey) as service:
async with service.get_blob_client(container, blobName) as client:
await client.upload_blob(BytesIO(data), overwrite=True)

Expected behavior
I expect to run the code without any warning.

[kashifkhan]

Thank you for the feedback @curia-damiano . We will investigate and get back to you asap.

[github-actions]

Thanks for the feedback! We are routing this to the appropriate team for follow-up. cc @jalauzon-msft @vincenttran-msft.

[weirongw23-msft]

Hi @curia-damiano Curia, thanks for your question.

What is the size of the data you are passing to upload_blob?

I did some investigation, and it looks like for block blobs the SDK reads the data from the stream (out of ByesIO) before passing it to the HTTP client.

This doesn't make much sense so it could potentially be a bug. I will discuss this with the team internally and get back to you on how we can best proceed to get rid of the warning.

[github-actions]

Hi @curia-damiano. Thank you for opening this issue and giving us the opportunity to assist. To help our team better understand your issue and the details of your scenario please provide a response to the question asked above or the information requested above. This will help us more accurately address your issue.

[curia-damiano]

In my scenario I am uploading mp3 files, from a minimum of 11Mb to a maximum of 59Mb.
In my first test, I get the warning with a test file of 40Mb.
Thank you for your help, I am looking forward to the resolution of this issue!