[BUG] Erroneous warning logs when performing CreateIfNotExistsAsync

Describe the bug The following code logs a warning:

var serviceCollection = new ServiceCollection();
serviceCollection.AddLogging(b => b.AddConsole());
serviceCollection.AddAzureClients(ab => ab.AddBlobServiceClient("UseDevelopmentStorage=true"));
var serviceProvider = serviceCollection.BuildServiceProvider();

var client = serviceProvider.GetRequiredService<BlobServiceClient>();
var container = client.GetBlobContainerClient(Guid.NewGuid().ToString());
await container.CreateIfNotExistsAsync();
await container.CreateIfNotExistsAsync(); // here

Expected behavior No warning is logged, we’re not doing anything out of the ordinary which should trigger a warning for our operators.

Actual behavior (include Exception or Stack Trace) It logs a warning, sample:

warn: Azure-Core[8]
      Error response [e5d2b146-8b40-47dc-8e0a-f12a623487d4] 409 The specified container already exists. (00.0s)
      Server:Windows-Azure-Blob/1.0,Microsoft-HTTPAPI/2.0
      x-ms-request-id:01ffe3d0-ee47-44d7-a35d-9303d108d19e
      x-ms-version:2020-04-08
      x-ms-error-code:ContainerAlreadyExists
      Date:Wed, 31 Mar 2021 07:31:06 GMT
      Content-Length:230
      Content-Type:application/xml

To Reproduce See example above.

Environment:

• Name and version of the Library package used: Azure.Storage.Blobs 12.8.1 (but earlier versions as well)
• Hosting platform or OS and .NET runtime version: up-to-date Windows 10 at least in NET Framework 4.8 and .NET Core 3.1
• IDE and version : up-to-date Visual Studio 2019

[pakrym]

Thinking about it, we can do something short-term as well. #20064 and https://github.com/microsoft/ApplicationInsights-dotnet/pull/2200

[msftbot[bot]]

Hi @drauch, since you haven’t asked that we “/unresolve” the issue, we’ll close this out. If you believe further discussion is needed, please add a comment “/unresolve” to reopen the issue.