fme_feature_type missing (sometimes)

What FME version do you use?

I am using FME Form 2024.1.2.1

I can’t reproduce what you describe using 2024.1.2.0 using an AttributeKeeper or a SubstringExtractor. It may be possible fme_feature_type is overwritten by an empty value when using something like a FeatureMerger?

Do you do production runs with or without FeatureCaching? Because if it works when running step by step using FeatureCaching, the order may be differen from when it is run in production?

I am still testing at the moment, so feature cashing is enabled which is why I could pinpoint exactly where the entries went missing. In this case it looked something like this:

FeatureJoiner (inspect cashed values: fme_feature_type has entries) outputs into SubstringExtractor input (inspect cashed values: fme_feature_type missing)

Unfortunately I can’t provide a screenshot right now as this error only occured after several hours of processing. I haven’t had this problem using smaller datasets.

   Edit: I have not tried without feature cashing yet, I might try that over night

Workspaces are generally quite a bit quicker when featurecaching is disabled. But when this does not occur when using a small sample set, and does happen with a bigger set, I would suspect it is data related...

I am not sure how this could be data related as there is nothing else happening between the two transformers, but maybe I am missing something. Will surely do some further testing. Just now I was able to produce the error once again.  
 

This is the FeatureJoiner Output (only fme_feature_type column shown)

And this is the AttributeKeeper which comes right after

This was somewhat solved by moving the AttributeKeeper behind the SchemaMapper or alternatively recreating fme_feature_type entries using an AttributeCreator. I still can’t explain the behaviour though.