Joël B.

This behaviour is kinda new, I first observed it beginning of December 2024 2025.

Hi Spiro T., indeed good question, and well it depends on use cases. Most of the times it's unchecked, so that during validation, the flow continues over pipelines containing snaps that write during execution only. Sometimes it's also unchecked, so that it's possible to count how many documents math a given filter, starting from 0. But my point here is during error: all my snaps are configured for "On error: stop pipeline execution", and indeed in case of error the pipeline is stopped with an error. But on such a snap failure, a downstream Gate will sometimes still output a document, even if marked as stopped in the monitor, as if the pipeline is not always able to stop the included Gate to complete execution, even if one of its inputs is failed. Said otherwise, to me it seems that the included Gate snap cannot be reliably stopped by the pipeline in case of error, which is highly undesirable.

So, do someone else here use Gate snaps in this fashion, and do you observe the same behavior? Otherwise, do you have a similar orchestration need, but use a different design to handle sequence and progress reporting?

And now, why I'm reporting this case: as exchanged with Olivier C., recently I observed that an error on a snap will stop the pipeline, but sometimes a downstream Gate snap will still output a document, and the Pipeline Execute snap will therefore have both an error and a normal output document. This is obviously breaking the expectation of having an exclusivity between error and document, and in this case, the top-pipeline will then start to follow both paths, resulting in normal treatment to go on while reporting the error, and in fine an incomplete document was produced.

And here's an illustation of sub-pipeline 1.1, ending with a Gate so that only one document goes to pipeline output

Here's the top-pipeline illustation:

hi, I would use a Gate snap to gather these two documents together, then do an object merge inside a Mapper snap, with Javascript expression to merge objects.