Prefect: "Quick Run" in Prefect UI never executes flow run

[petermorrow]

Description

Trying to run a registered flow with Prefect UI's "Quick Run" option on the flow's detail page creates a flow run that is never executed. The flow run remains in a "Late Runs" state indefinitely.

Expected Behavior

"Quick Run" runs the flow immediately.

Reproduction

Configure and start Prefect's UI

prefect backend server
prefect server start

Register simple flow

import time
import random

from prefect import task, Flow


@task()
def fail_randomly():
    """Fails randomly with a 30% probability of failure"""
    time.sleep(random.randint(1, 3))
    if random.randint(1, 10) <= 3:
        raise TypeError('Random Error!')


with Flow('Random Failure') as flow:
    for i in range(10):
        fail_randomly()


flow.register()

Navigate to the flow's detail page and click "Quick Run". Then navigate back to the prefect dashboard and wait for the flow run to appear. The UI will show the flow run in the "Late Runs" category indefinitely. Here's a screenshot from my local deployment:

Environment

{
  "config_overrides": {},
  "env_vars": [],
  "system_information": {
    "platform": "Darwin-19.4.0-x86_64-i386-64bit",
    "prefect_version": "0.10.5",
    "python_version": "3.7.7"
  }
}

[cicdw]

Hi @petermorrow - this is expected behavior; all flows must be run through an appropriately configured Agent. In your case, if you run prefect agent start on the same machine you registered your Flow from you'll see the work begin. I recommend working through our Deployment Tutorial to learn about how this all works!

[petermorrow]

Thanks for the clarification @cicdw! Maybe the UI could show data regarding agents? Like how many agents are available and what tasks were run by which agent.

[cicdw]

Ah yes, this is available on Prefect Cloud (including the free Scheduler tier) but is not currently available in the open source server for infrastructure / implementation specific reasons