Add empty param name support

[cofob]

Test code:

import asyncio

from taskiq import InMemoryBroker

from taskiq_pipelines import EMPTY_PARAM_NAME, Pipeline, PipelineMiddleware

broker = InMemoryBroker()
broker.add_middlewares(PipelineMiddleware())


@broker.task
async def add_one(value: int) -> int:
    return value + 1


@broker.task
async def do_nothing() -> None:
    print("I'm doing nothing.")


async def main() -> None:
    # Never forget to call startup in the beginning.
    await broker.startup()

    pipe = (
        Pipeline(broker, add_one).call_next(do_nothing, param_name=EMPTY_PARAM_NAME)
    )
    task = await pipe.kiq(2)

    await asyncio.sleep(2)


if __name__ == "__main__":
    asyncio.run(main())

[s3rius]

@cofob, thanks you very much for contribution.

I have an Idea. I guess, it would be really nice to create a separate function that sets this parameter to EMPTY_PARAM_NAME and do not expose the constant to users. You may call it call_after and just remove param_name argument.

As I see it, it would be easier since you would not need to import anything and it would be easier to maintain backward compatibility.

async def main() -> None:
    # Never forget to call startup in the beginning.
    await broker.startup()

    pipe = Pipeline(broker, add_one).call_after(do_nothing)
    task = await pipe.kiq(2)

    await asyncio.sleep(2)

What do you think?

[cofob]

@s3rius added call_after. Please review.