How to make a flow fail (return an error, exception)

Flows
1

Hi Everyone,

how can I make a flow fail, that a calling flow will be aware of the failure.

I have an advanced flow, which I start from another advanced flow (like an subroutine) and when in the subroutine-flow an error occurs, I want to give this back to the calling flow to proceed on the red line.

thanks in advance
bischowski

1 Like
2

There are no subroutines.

Best is to call the original flow with for example a number tag that indicates the Error.

The excellent app Advanced Triggers has an option to return values but after trying it, I think the use case does not justify the complication.

3

You could set a variable in the called routine to indicate success or failure. E.g. set a boolean xxxFailed to true at the start and false at the successful outcome(s). You can then test the variable in the calling routine. I’ve just checked and when a called flow finishes it does return control to the calling flow so you can chain a test of the variable after the call.

For more information, you could use a string variable to store error messages and use ‘success’ to indicate successful completion.

If you don’t get control back in your situation, you could try adding a branch before the call with a delay before testing the variable. A kludge, but it might do what you need.

Andy

4

In 3+ years I’ve never experienced a flow itself fails for unknown reasons
It’s always:

  • me: I did something stupid, like deleting a variable which still was used in a flow
  • a variable which got an invalid value somehow
  • app crash / paused app: this causes all related flowcards to become unavailable. The flow breaks, and stops functioning, but,
    This wonderful app monitors all those variables, breaks, errors and mistakes and notifies you: Flow Checker

Advice: add Simple Log app log cards to each and every part of your flows, to be able to search historical data.
It even has a script to add log cards to all flows.

2 Likes
5

Well, starting a flow from another flow with text (JSON in this case) seems to be very close to a subroutine/procedure call in my opionion. The start-flow-with-text-card has a error-branch. How to use this branch, when there is no way to make the flow fail/return error state?

But nevertheless, thanks for the feedback. SimpleLog needs to do the job until this might be added in the future.

6

Grab your chance here, and ask why its absent, and/or propose what you’d like to see:

1 Like
7

There are a lot more important things to do for athom. Many of them are already asked. I will try to find the time to join the event, but … hmm, how to say. Even though I love homey for many years, I’m not a athom fanboy. Even if they created an amazing product, I don’t like their closed doors politics and the way they handle problems.

1 Like