Blueprint .build() and .get_user_function() missing from PyPI 1.4.0 release (present in repo/tag)

[Mirabis]

🐛 Describe the bug

The official documentation and repo samples for Durable Functions Python v2 (Blueprint pattern) show a .build().get_user_function().orchestrator_function accessor for orchestrator unit testing. However, after installing azure-functions-durable==1.4.0 from PyPI, neither DFApp nor Blueprint exposes a .build() method. This makes it impossible to use the recommended test pattern for orchestrators.

🤔 Expected behavior

The .build() method (and .get_user_function()) should be available as shown in the official repo and samples for v1.4.0, enabling the following test pattern:

orchestrator = bp.build().get_user_function().orchestrator_function

This is important for maintainable, idiomatic unit tests using the Blueprint pattern.

☕ Steps to reproduce

• Install the latest SDK:

  pip install azure-functions-durable==1.4.0

• Try to access .build() on a Blueprint or DFApp instance:

  from azure.durable_functions.decorators.durable_app import Blueprint, DFApp
  bp = Blueprint()
  app = DFApp()
  bp.build()  # AttributeError
  app.build()  # AttributeError

• Observe error:

  AttributeError: 'Blueprint' object has no attribute 'build'
  

• Official sample using .build()

Pattern: Durable Functions v2, Blueprint pattern, local development (macOS, Python 3.13).

⚡If deployed to Azure

N/A – this is a local development/testing issue with the SDK package.

• Timeframe issue observed: Ongoing since v1.4.0 release
• Function App name: N/A
• Function name(s): N/A
• Azure region: N/A
• Orchestration instance ID(s): N/A
• Azure storage account name: N/A

Additional context:

• The repo/tag for 1.4.0 includes .build() and the new test pattern, but the PyPI release does not.
• This blocks adoption of the official Blueprint unit test pattern and causes confusion for users following the docs.
• Please ensure the next PyPI release includes the .build() and .get_user_function() APIs as present in the repo/tag, or clarify in the docs if a dev/nightly build is required.

[Mirabis]

Through trial and error I was able to find a workaround but that might not be the intended use:

from azure.durable_functions import Blueprint
from azure.durable_functions.models import TaskBase

def get_orchestrator_function_from_blueprint(bp: Blueprint) -> Callable:
    """
    Extract the orchestrator generator function from a Blueprint.

    This helper abstracts the internal API for accessing the orchestrator function.
    Microsoft's documentation shows bp.build(), but the actual implementation requires
    accessing the first registered function builder: bp._function_builders[0].build()

    This pattern ensures that:
    - Tests are consistent and maintainable
    - Changes to the internal API only need to be updated in one place
    - Your test code follows Microsoft's conceptual pattern while handling the implementation reality

    Reference:
    - https://learn.microsoft.com/azure/azure-functions/durable/durable-functions-unit-testing-python

    Args:
        bp: A Blueprint instance from azure.durable_functions

    Returns:
        The orchestrator function (a generator function that yields TaskBase objects)

    Raises:
        IndexError: If the Blueprint has no registered function builders
        AttributeError: If the expected methods/attributes are not found
    """
    func_builder = bp._function_builders[0]
    built_func = func_builder.build()
    user_func = built_func.get_user_function()
    return user_func.orchestrator_function

which than replaces the old:

...
        # This line fails with: AttributeError: 'Blueprint' object has no attribute 'build'
        func_call = my_orchestrator.build().get_user_function().orchestrator_function
 ...

with the following working solution:

...
        func_call = get_orchestrator_function_from_blueprint(my_orchestrator)
...