Hi, So we have a number of nodes in our topology that need to do things like checking a database, e.g.
* We need a filter step to drop events on the floor from systems we are no longer interested in * We need a step that outputs on a side-channel if the event is for an object where the parent is not currently known to the database. Right now we are grabbing a JDBC connection for each node in the topology that needs to talk to the database and storing the connection in a transient field (to exclude it from the serialized state) What I'd really like to do is have a JDBC connection pool shared across the entire topology as that way we could have the pool check for stale connections, etc. Does anyone have any tips for doing this kind of thing? (My current idea is to maintain a `static final WeakHashMap<ClassLoader,ConnectionPool>` in the main class... but that feels very much like a hack) What I'm really looking for is some form of Node Transient State... are there any examples of this type of think. Flink 1.8.x Thanks, -Stephen
