Azure-sdk-for-python: Container client fails slowly instead of ResourceNotFound

[AkhilGNair]

• azure-storage-blob
• 12.3.2
• Ubuntu 20.04
• 3.8.2

Describe the bug
I've been advised in #12744 to open a new issue for this behaviour.

I'm trying to use

from azure.storage.blob import ContainerClient

client = ContainerClient("storage1234567", container_name="container-01")
client.get_container_properties()

to check if a container exists. I had expected either an immediate ResourceNotFound or otherwise some unauthorised message - basically anything that would allow me to fail fast. Instead the command runs for about 2 minutes, retrying twice (three times in total, I believe with some backoff) resulting in

azure.core.exceptions.ServiceRequestError: <urllib3.connection.VerifiedHTTPSConnection object at 0x7f7bd6ef8bb0>: Failed to establish a new connection: [Errno -3] Temporary failure in name resolution

I have also tried all the timeout kwargs I can think of, timeout, read_timeout, connection_timeout, socket_timeout (supplied as numeric or tuple) and none make a difference.

Is there a way to short-circuit this and allow me to catch some faster failure?

To Reproduce

from azure.storage.blob import ContainerClient

client = ContainerClient("storage1234567", container_name="container-01")
client.get_container_properties()

Expected behavior
@tasherif-msft advises

Hi @AkhilGNair, interesting issue you've come across, but this is actually an unexpected behavior. The error you're getting implies the request was not sent (you would receive a ResourceNotFound response from the server if the request was sent).

My expectation is that I can quickly catch a failure!

[xiafu-msft]

Hi @AkhilGNair

The error says "Temporary failure in name resolution"
can you try to change the container name to "container01"

[msftbot[bot]]

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

[msftbot[bot]]

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

[tasherif-msft]

Hi @AkhilGNair any updates on the issue? is it still persistent even after the container renaming?

[AkhilGNair]

Sorry, haven't been able to check this yet - will update tomorrow morning UK time! Thanks

[AkhilGNair]

Sorry for the long delay!

When trying

>>> client = ContainerClient("storage1234567", container_name="container01")  # changed from "container-01"
>>> client.get_container_properties()

I get the same error. A very long wait time, followed by

azure.core.exceptions.ServiceRequestError: <urllib3.connection.VerifiedHTTPSConnection object at 0x7f5713a79d00>: Failed to establish a new connection: [Errno -3] Temporary failure in name resolution

Thanks!

[tasherif-msft]

Hi @AkhilGNair,

On a closer look at your example, I noticed you put storage1234567 as your account url, which is incorrect. Your account url for the blob service should look something like: https://<STORAGE_ACC_NAME>.blob.core.windows.net or just <STORAGE_ACC_NAME>.blob.core.windows.net.

So assuming your account name is storage1234567, the account url would be: https://storage1234567.blob.core.windows.net You also have to ensure that you have set your credentials to be able to access that storage account and its resources, i.e, using a connection string or generating a SAS for example.

Here is two good walk-throughs for this: https://docs.microsoft.com/en-us/python/api/overview/azure/storage-blob-readme?view=azure-python and https://docs.microsoft.com/en-us/python/api/azure-storage-blob/azure.storage.blob.containerclient?view=azure-python

This would also explain why the request was not sending.

Your issue also made me realize that we need to add an extra check to our account_url validation :)

Let me know if this fixes your issue.

[AkhilGNair]

This is great (and makes me feel stupid :wink:) - the validation would be perfect as it was just the URL validation I was missing.

Creds are fine, no issue there - just wanted to catch the unauthorised error.

Thank you!