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_*Prefect 2.0* (open-source)_
Hi! I’m currently trying to set up a simple flow to run dbt in the following way:
1. check `dbt source freshness`
    a. If I get an error, fail the flow
2. run `dbt build`
I’ve figured out a way to fail the flow by scanning the result from PrefectFuture but somehow this doesn’t feel right (simplified code snippet in :thread:).
Two questions :pray::
1. Is there a “better” way to handle this?
2. I’d also like to add some kind of notification when the flow fails (email and/or slack) - I can’t find any integration within prefect itself, so would the recommended route be to send a webhook directly in the flow?

```def dbt_flow(env: str = "dev"):
    logger = get_run_logger()

    freshness = shell_run_command(
        command=f"dbt source freshness -t {env}",
        return_all=True
    )

    result = freshness.result()
    for res in result:
        assert "ERROR STALE" not in res

    <http://logger.info|logger.info>(f"Source is fresh, continuing...")

    build = shell_run_command(
        command=f"dbt build -t {env}"
    )```

Hello Dominik! In regards to your first question, let me do a little research on that and I'll get back to you. In regards to the second one, yes, I believe the best way to send an alert through email/slack would be to pass a webhook into the flow. Here is an <https://discourse.prefect.io/t/how-can-i-send-automated-failure-notifications-is-there-a-way-to-get-a-full-exception-traceback-in-a-failure-notification/115|example> on how to do that.

If I understand what you are doing correctly, I'm not sure that failing the entire flow is really necessary. You can add an `if` statement to your flow to determine whether or not to run `dbt build` based on the result of the `check dbt source freshness.`Here is some <https://orion-docs.prefect.io/concepts/tasks/#using-results-from-tasks|documentation> where you can find an example of using results from tasks within the context of a flow.

Thanks for the reply, Bianca! :raised_hands:

Okay great, a webhook looks easy enough to implement and just plug into flows.

That's a fair point about whether or not the flow should fail; though I think my question is more about whether parsing the result to look for the errors like that is a good idea at all! :thinking_face:

Ah! Thank you for clarifying. I'm not terribly familiar with dbt, so I'll answer this the best of my capabilities. To my understanding, if you'd like to run `dbt build`  in response to the "ERROR STALE" error message specifically, then parsing the result to look for that error is a good idea.