[BUG] Caching and BlobClient.DownloadAsync() Response x-ms-client-request-id does not match the original expected request id

[simader]

In an .netFramework-Project with requestCaching activated the second time a blob is requested, a RequestFailedException is thrown.

Azure.RequestFailedException: 'Response x-ms-client-request-id '3742a081-3d05-493e-9b97-c5cbcd70c659' does not match the original expected request id, '890534a7-43be-46b7-bcd0-f6c3e3cfef12'.

if caching is deactivated it works fine.

<system.net>
    <requestCaching isPrivateCache ="true" disableAllCaching="false" defaultPolicyLevel="CacheIfAvailable" unspecifiedMaximumAge="7.00:00:00" />
  </system.net>

Environment:

• Name and version of the Library package used: Azure.Storage.Blobs 12.10.0 (newest)
• Hosting platform: .net Framework 4.7.2

AzureBlobBug.zip

[ghost]

Thank you for your feedback. This has been routed to the support team for assistance.

[ghost]

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

Issue Details

---

In an .netFramework-Project with requestCaching activated the second time a blob is requested, a RequestFailedException is thrown.

Azure.RequestFailedException: 'Response x-ms-client-request-id '3742a081-3d05-493e-9b97-c5cbcd70c659' does not match the original expected request id, '890534a7-43be-46b7-bcd0-f6c3e3cfef12'.

if caching is deactivated it works fine.

<system.net>
    <requestCaching isPrivateCache ="true" disableAllCaching="false" defaultPolicyLevel="CacheIfAvailable" unspecifiedMaximumAge="7.00:00:00" />
  </system.net>

Environment:

• Name and version of the Library package used: Azure.Storage.Blobs 12.10.0 (newest)
• Hosting platform: .net Framework 4.7.2

AzureBlobBug.zip

Author:	simader
Assignees:	SaurabhSharma-MSFT
Labels:	Storage, Service Attention, Client, customer-reported, question, needs-team-attention
Milestone:	-

[SaurabhSharma-MSFT]

@simader We are doing investigation on the same. We will get back to you.

[amishra-dev]

@kasobol-msft Kamil could you please look at this?

[kasobol-msft]

@simader Could you explain why would you want system.net cache to cache storage responses while using the SDK? Couple of thoughts why this might not be best idea.

The Blob SDK (and other Storage SDKs) check if request id sent to service is replied back by the service in a policy that's applied to every request, see here.
Many features of the SDK won't work correctly if there's no exchange with the service, thus resulting in possible bugs in the apps.

The caching mechanism present in .NET Framework hasn't been carried forward (see here). Usage of such a global cache can be source of many errors in the app. We recommend against using it.
Instead we recommend to cache results of the SDK calls in memory if that's something you desire. Alternatively, if you still pursue the global request caching, I'd recommend to use raw HttpClient or WebRequest to download resources - as I mentioned we can't guarantee correctness of the SDK implementation if blobal system.net cache is enabled (for example when we chunk the downloads).

[ghost]

Hi @simader. Thank you for opening this issue and giving us the opportunity to assist. We believe that this has been addressed. If you feel that further discussion is needed, please add a comment with the text “/unresolve” to remove the “issue-addressed” label and continue the conversation.

[simader]

Hello,
Yes, we removed this caching again, because of some other unexpected behaviour.
Best,
Andreas