Add AzureBlobStorageContainer block

[desertaxle]

Adds an AzureBlobStorageContainer block as a replacement for the Azure block in the core library. Works for both deployment flow code storage and result storage.

Closes #135

Example

from prefect_azure import AzureBlobStorageCredentials
from prefect_azure.blob_storage import AzureBlobStorageContainer

credentials = AzureBlobStorageCredentials(
    connection_string="connection_string",
)
container = AzureBlobStorageContainer(
    container_name="container",
    credentials=credentials,
)
# Downloads all files from the specified folder
container.download_folder_to_path(
    from_folder="folder",
    to_folder="local_folder"
)

Screenshots

Checklist

• References any related issue by including "Closes #" or "Closes ".
  • If no issue exists and your change is not a small fix, please create an issue first.
• Includes tests or only affects documentation.
• Passes pre-commit checks.
  • Run pre-commit install && pre-commit run --all locally for formatting and linting.
• Includes screenshots of documentation updates.
  • Run mkdocs serve view documentation locally.

[serinamarie]

I'd expect to get this error sooner but that's probably for another PR (I've created an issue for it):

ValueError: Connection string is either blank or malformed.

from prefect_azure import AzureBlobStorageCredentials
from prefect_azure.blob_storage import AzureBlobStorageContainer

my_connection_string = "dsfdsf"  # fake

credentials = AzureBlobStorageCredentials(
    connection_string=my_connection_string,
)
container = AzureBlobStorageContainer(
    container_name="testing314",  # container exists
    credentials=credentials,
)
# Downloads all files from the specified folder
container.download_folder_to_path(
    from_folder="requirements.txt",
    to_folder="local_folder"
)

12:48:34.514 | INFO    | prefect.AzureBlobStorageContainer - Downloading folder from container testing314 to path local_folder
Traceback (most recent call last):
  File "/Users/bean/code-oss/prefect-azure/prefect_azure/credentials.py", line 65, in inner
    return func(*args, **kwargs)
  File "/Users/bean/code-oss/prefect-azure/prefect_azure/credentials.py", line 259, in get_container_client
    container_client = ContainerClient.from_connection_string(
  File "/Users/bean/code-oss/prefect-azure/azurevenv/lib/python3.10/site-packages/azure/storage/blob/_container_client.py", line 270, in from_connection_string
    account_url, secondary, credential = parse_connection_str(conn_str, credential, 'blob')
  File "/Users/bean/code-oss/prefect-azure/azurevenv/lib/python3.10/site-packages/azure/storage/blob/_shared/base_client.py", line 371, in parse_connection_str
    raise ValueError("Connection string is either blank or malformed.")
ValueError: Connection string is either blank or malformed.

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "/Users/bean/code-oss/prefect-azure/qa.py", line 14, in <module>
    container.download_folder_to_path(
  File "/Users/bean/code-oss/prefect-azure/azurevenv/lib/python3.10/site-packages/prefect/utilities/asyncutils.py", line 259, in coroutine_wrapper
    return call()
  File "/Users/bean/code-oss/prefect-azure/azurevenv/lib/python3.10/site-packages/prefect/_internal/concurrency/calls.py", line 431, in __call__
    return self.result()
  File "/Users/bean/code-oss/prefect-azure/azurevenv/lib/python3.10/site-packages/prefect/_internal/concurrency/calls.py", line 317, in result
    return self.future.result(timeout=timeout)
  File "/Users/bean/code-oss/prefect-azure/azurevenv/lib/python3.10/site-packages/prefect/_internal/concurrency/calls.py", line 178, in result
    return self.__get_result()
  File "/Users/bean/.pyenv/versions/3.10.4/lib/python3.10/concurrent/futures/_base.py", line 391, in __get_result
    raise self._exception
  File "/Users/bean/code-oss/prefect-azure/azurevenv/lib/python3.10/site-packages/prefect/_internal/concurrency/calls.py", line 388, in _run_async
    result = await coro
  File "/Users/bean/code-oss/prefect-azure/prefect_azure/blob_storage.py", line 283, in download_folder_to_path
    async with self.credentials.get_container_client(
  File "/Users/bean/code-oss/prefect-azure/prefect_azure/credentials.py", line 72, in inner
    raise ValueError(HELP_FMT.format(help_url=HELP_URLS[key])) from exc
ValueError: Please visit https://docs.microsoft.com/en-us/azure/storage/blobs/storage-quickstart-blobs-python#copy-your-credentials-from-the-azure-portal for retrieving the proper connection string.

[serinamarie]

LGTM! 🔥