Affects Version/s: None
Fix Version/s: 1.2
sendTo(stream), sendTo(table) and sink are currently terminal operators in the High Level API. They don't return a MessageStream, and hence do not allow chaining of further operators.
Consider the following use case:
Consume a message -> send an event denoting processing start -> do some processing -> send an event denoting processing end.
Currently there's no good way to do this, since:
- HL API does not allow chaining further operations on sendTo
- HL API does not guarantee order of execution across multiple operators chained on the same operator.
The only way to do this today will be to use a sink function, which is not great.
One consideration when making sendTo(stream) et al. non-terminal: unlike partitionBy, which returns data in the re-keyed MessageStream partition, sendTo will return the data in the original message stream partition. This will need to be clearly called out.