[NIFI-3216] Add ability to wait for N signals to Wait/Notify processors

• Type: Improvement
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.2.0
• Fix Version/s: 1.2.0
• Assignee: Koji Kawamura
• Reporter: Bryan Bende
• Created: 16/Dec/16 15:34
• Updated: 19/Jan/17 20:19
• Resolved: 19/Jan/17 20:19

Description

The recently added Wait and Notify processors allow a flow file to be held at the Wait processor until a signal is received in the Notify processor. It would be nice to be able to wait for N signals before releasing.

One way this could be done is to have a property like "Signal Count" on the Wait processor, and then count the keys in the cache starting with some pattern, and release when the # of keys equals the signal count.

This would require the ability to get all the keys from the cache, or at least get all keys matching a pattern:

https://issues.apache.org/jira/browse/NIFI-3214

Issue Links

• relates to: NIFI-3214 Add a method to DistributedMapCacheClient to replace existing key only if it hasn't been changed
• links to: GitHub Pull Request #1420