For a given flow if a task fails I am wanting to write the s

Question

For a given flow if a task fails I am wanting to write the state to my local machine and be able to load it back up later I am looking into state handlers and persisting output using `LocalResult` but I m wondering if there are Prefect features that are particularly appropriate for this use case

Dylan · Answer

Hey < tkanas> When you say state here can you elaborate a bit Do you want to write the result of previous tasks the flow context the state object for that task run

Dylan · Answer

To cache results take a look here <https docs prefect io core concepts persistence html>

tkanas · Answer

That s something we are still thinking about Basically the state of the flow just before failure so that a user could possibly load it back up and inspect it later

Dylan · Answer

Hmmm but this is in response to failure

Dylan · Answer

So you want to catch all exceptions write something down and then fail the task run

tkanas · Answer

I think so I m still thinking about what the something is and what the best way is of writing it down So far I have been looking at using a `state handler` that would check `state is failed ` and then dispatch to the thing that writes the state in conjunction with a persisting method as described in the link you provided above I just haven t figured out the best way of doing it

Dylan · Answer

So I think the key point here is that you want to know the state before the failure

Dylan · Answer

I m not sure a state handler will help with that since they fire on state change

Dylan · Answer

However have you tried setting up Prefect Server or Prefect Cloud If you have an orchestration layer you would be able to see the state of the failed flow along with logs

Dylan · Answer

Or do you want to load a certain state of the world into a python interpreter locally

Dylan · Answer

Another way of asking my question are you having trouble identifying an issue inside a task or testing a solution

tkanas · Answer

Saving and loading a state of the world sounds like it might fit the bill Preferably the state right before failure If that s not possible then maybe the state right after failure

tkanas · Answer

How would you save and load a state of the world

Dylan · Answer

Locally I m not sure we have a way to do this

Dylan · Answer

But if you re using Prefect Server Cloud you can manipulate task run states and flow run states with the graphql API

Dylan · Answer

that would allow you to watch a flow run in a given state of the world

tkanas · Answer

OK I will look into that Thanks

Dylan · Answer

Anytime