[workflow] log is not pushed to driver if run multiple times

import ray
from ray import workflow
ray.init(address='auto')
workflow.init()

@workflow.step
def s():
    return 10


print(s.step().run())

Run the above script multiple times and only the first one will print the log correctly. Need to always push the log to the driver.

[iycheng]

@lchu-ibm we don’t need to fix it in ray core layer since this is the behavior we’d like.

The thing here is that we need to redirect the log to the right driver by updating the logging library.

We don’t need to do this for most jobs. For workflow, we need to do this because it damages UX.

[lchu-ibm]

Even for non-detached actor, the same issue will be there. E.g. in the same example above, if the actor is not detached but script 1 is not exited, script 2 has the same issue of lost logs in the driver.