Hi all 😄 I have little problem, prefect version 2.7.8 a flow is defined in test.py which content is very simple:

from prefect import flow

@flow
def myflow(x: int):
    return x ** x

I want to run this flow with a deployment so i do the following:

from prefect.deployments import Deployment, run_deployment
from test import myflow

deployment = Deployment.build_from_flow(flow=myflow, name="test", version=1)
deployment_uuid = deployment.apply()
output = run_deployment(name=f"{deployment.flow_name}/{deployment.name}", parameters={"x": 3})

Everything works fine, but the program never returns 😢 it's stuck on the "run_deployment" When I do

prefect flow-run ls

I see that my flow-run was created but is stuck in "scheduled" state. I have the same problem if I run this code within a "if name == main" block, if I specify a work queue name, or add a schedule time in the future. Do you have any idea ? Thanks in advance for your precious help 💓

Hi @Ethienne Marcelin are you running an agent?

Yes I tried with an agent, and specified the work queue name I started the agent with prefect agent star -q test

ahh, try passing

work_queue_name="test"

to your

build_from_flow

call

That’s what i did but it had no effect :(

hmm could you try doing a CLI command just as a sanity check?

prefect deployment build test.py:myflow -n test -q test --apply

Yes of course ! I’m in the subway so i’ll try when i’m back home

sounds good 🙂

By doing the command provided it works, but I wonder what i'm missing in my code🤔

sure thing 😄 that's why we're here

Is it possible to start the agent programatically ? Or i must use the CLI ?

there's not a python interface for running agents in prefect 2, I'd recommend using the CLI to start the agent process what's your use case that you'd want do it programmatically?

i don't want to manage the agent "by hand" with the cli At then end of my program, how do I kill the agent without hitting ctrl-c ? Should I use prefect.infrastructure ?

prefect infrastructure is a way of telling your agent how it should actually execute your flow run, if you don't specify infrastructure for a deployment, your agent will assume that it should create a local process (where the agent is running) for your flow run usually agents are meant to be a long-lived process, typically people will start an agent on a VM or a kubernetes pod using the helm chart and just keep it running so it can pick up future flow runs so I guess the short answer is that you would need to manually kill the agent if you only wanted it to exist for the duration of a flow run but its totally valid to just not create a deployment and just run your flow when you want, the runs will still show up in your UI (no agent required) - its just that when you want to attach a schedule or alter flow run parameters from the UI, you'll need a deployment and an agent that can pick up its flow runs

Ok I see I misunderstood agents ! You're the best Nate thanks :))

sure thing! lmk if any other questions come up