Hi, Referring to the explanation found at the following link under (Stream processing triggered from an external source)
https://beam.apache.org/documentation/patterns/file-processing/ While implementing this solution I am trying to figure out how to deal with the fact that my pipeline, which was bound, has now become unbound. It exposes me to windowing/triggering concerns which I did not have de deal with before and in essence are unnecessary since I am still fundamentally dealing with bound data. The only reason I have an unbound source involved is as a trigger and provider of the file to be processed. Since my pipeline uses GroupByKey transforms I get the following error. Exception in thread "main" java.lang.IllegalStateException: GroupByKey cannot be applied to non-bounded PCollection in the GlobalWindow without a trigger. Use a Window.into or Window.triggering transform prior to GroupByKey. Do I really need to add windowing/triggering semantics to the PCollections which are built from bound data ? Thanks for any pointers. Serge
