Hello there ! I'm having trouble using

get_task_run_result

to access data from a subflow. This example should reproduce the issue :

from prefect import Flow, task, Parameter, unmapped
from prefect.tasks.prefect import create_flow_run, get_task_run_result

@task(slug="plus-one")
def plus_one(x: int):
    return x+1

with Flow("Child") as child_flow:
    x = Parameter("x", default=10)
    po = plus_one(x)

@task
def get_params():
    return [{"x": i} for i in range(5)]

with Flow("Parent") as parent_flow:
    params = get_params()
    flow_run_ids = create_flow_run.map(flow_name=unmapped("Child"), parameters=params)
    results = get_task_run_result.map(flow_run_ids, unmapped("plus-one"))

When running the parent flow, I get issues that look like :

Error during execution of task: ValueError("No task runs found while querying for task runs where {'task': {'slug': {'_eq': 'plus-one'}}, 'flow_run_id': {'_eq': '3316e187-adda-461d-814f-29a6ffc059a4'}, 'map_index': {'_eq': -1}}")

Is there something I'm missing with how slugs work ?

I think you need to add -1 to get the slug name, so it would be:

unmapped("plus-one-1")

I get the same issue with

results = get_task_run_result.map(flow_run_ids, unmapped("plus-one-1"))

unfortunately. Both flows are registered in the script, I just removed it in order to not paste too much code in here.

does it work if you don’t use mapping?

Does not seem to be working with either

plus-one-1

or

plus-one

when mapping is removed. Running on

0.15.9

if at all relevant.