[Cosmos] fix partition_key type in create container method

[Hussein Awala (hussein-awala)]

Description

This PR updates the type hint of partition_key param in the methods create_container and replace_container by making it optional, where None is an accepted value to create nonpartitioned containers.

related: apache/airflow#38196
related: #33341

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• The pull request does not introduce [breaking changes]
• CHANGELOG is updated for new features, bug fixes or other significant changes.
• I have read the contribution guidelines.

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[github-actions]

Thank you for your contribution Hussein Awala (@hussein-awala)! We will review the pull request and get back to you soon.

[Hussein Awala (hussein-awala)]

@microsoft-github-policy-service agree

[Anna Tisch (annatisch)]

Thanks so much for this Hussein Awala (@hussein-awala) - changes look good to me, but adding Simon Moreno (@simorenoh) and bambriz to confirm from the service team.

[Simon Moreno (simorenoh)]

hi Hussein Awala (@hussein-awala) - I'm not entirely positive on the mypy issue that is present for you folks at apache airflow, but these are not changes that we can do on our end. We have not allowed for the creation of non-partitioned containers for years now, and the current improvements we have made to our typing within the Cosmos SDK are relevant and up to date with the behavior we have for the client and for the underlying service. Since the beginning of the async client, this has been marked as a non-optional field for the relevant methods:

PR in case you're curious: https://github.com/Azure/azure-sdk-for-python/pull/21404/files#diff-a274a8107879de7dace0a296bd1f57274e12e22a764ed77c0c0579c275980e1c

And that is for good reason - like I mentioned, this is not behavior we have allowed for several years now and users should be seeing an error when attempting to use None for a partition key definition:

As such, I'll be closing this PR.

[Hussein Awala (hussein-awala)]

We have not allowed for the creation of non-partitioned containers for years now

This seems incorrect, the method still accepts None which is handled by the method without raising an exception:

azure-sdk-for-python/sdk/cosmos/azure-cosmos/azure/cosmos/database.py

Lines 224 to 225 in a7b794d

	if partition_key is not None:
	definition["partitionKey"] = partition_key

azure-sdk-for-python/sdk/cosmos/azure-cosmos/azure/cosmos/aio/_database.py

Lines 228 to 229 in a7b794d

	if partition_key is not None:
	definition["partitionKey"] = partition_key

And from Cosmos documentation:

Azure Cosmos DB supports creating containers without a partition key. Currently you can create nonpartitioned containers by using Azure CLI and Azure Cosmos DB SDKs (.NET, Java, NodeJs) that have a version less than or equal to 2.x. You can't create nonpartitioned containers using the Azure portal. However, such nonpartitioned containers aren’t elastic and have fixed storage capacity of 20 GB and throughput limit of 10K RU/s.

[Simon Moreno (simorenoh)]

Hussein Awala (@hussein-awala) I see what you mean - while that may look like redundant code, we actually have it there on purpose to ensure we don't fill out the container definition with a None partition key. Reason for that being that the error message returned by the service is a lot more informative that way. Compare the one I sent before vs. this one:

You also only included part of that page on documentation for migrating from non-partitioned collections (which are even marked as legacy in that same document) to newer partitioned ones. It is also mentioned there that the behavior is only available for versions <= 2.x.