Running dependent flows with parameters

Hi! I dont see in doc, how i can add parameters in b_flow from a_flow and dir parameter. I think for this i can use local context in b_flow from a_flow. May be add upstream_tasks with parameters?

Flow A:

@task
def any_work(a: str) -> str:
    return f'/tmp/{a}'

with Flow('a_flow') as flow:
    name = Parameter('name', default='all')
    result = any_work(name)

Flow B:

@task
def any_work(a: str, b: str) -> str:
    return f'{a}/{b}'

with Flow('b_flow') as flow:
    home = Parameter('home', required=True)
    dir = Parameter('dir', default='any')

    result = any_work(home, dir)

Flow C:

a_flow = FlowRunTask(flow_name='a_flow', wait=True)
b_flow = FlowRunTask(flow_name='b_flow', wait=True)

with Flow('c_flow') as flow:
    name = Parameter('name', default='all')
    dir = Parameter('dir', default='any')

    a_flow_state = a_flow(parameters={'name': name})

    # this error code, but how i can add parameters in `b_flow` from `a_flow` and dir parameter?
    result = b_flow(
        upstream_tasks=[a_flow_state],
        parameters={
            'home': a_flow_state.result,
            'dir': dir,
        },
    )

[madkinsz]

Thanks for sharing your task @peterroelants – this should be resolved by #4563

[dmvieira]

I did this workaround to retrieve results:

import time
from prefect.tasks.prefect import StartFlowRun
from prefect import Flow, task, Client

task1= StartFlowRun(
      flow_name="test_flow",
      project_name="test_project",
      wait=False
)

with Flow("Call Flow") as flow:
    end_flow = task1()

state = flow.run()
flow_id = state.result[end_flow].result
client = Client()

while not client.get_flow_run_info(flow_id).state.is_finished():
    time.sleep(5)
info = client.get_flow_run_info(flow_id)
last_task = info.task_runs.pop()
res = last_task.state.load_result(last_task.state._result).result

print(res)