I’m writing my own spout, backed by a persistent store outside of storm. What I need to know is whether Storm guarantees that a spout will always be called with ack() or fail() for a given tuple. I.e. even if the spout process dies, another one will make the call.
If this is true, then I can remove the record from storage in nextTuple() and put it back on in fail(), and I’ll be sure I’ll never lose any even in case of failure. If this is not true, then I need to keep the record in the underlying storage after nextTuple() and don’t take it off until ack(). This just makes it harder because subsequent nextTuple() calls have to know to skip the in progress ones. So, I hope Storm provides this guarantee. Thanks
