[NIFI-259] Framework should offer Processors/extensions a way to manage simple state

• Type: Sub-task
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 0.5.0
• Component/s: Core Framework
• Labels: migration
• Assignee: Mark Payne
• Reporter: Joe Witt
• Created: 14/Jan/15 12:08
• Updated: 07/Feb/16 21:14
• Resolved: 06/Feb/16 03:36

Description

It is not uncommon for processors to need managed state which persists across restarts. One good example of this is the GetHTTP processor which needs to save state of the last cache/e-tag information it received from the server it interacts with so that it can avoid constantly pulling an unchanged resource.

Rather than making processors roll their own persistant state management perhaps we can offer something to them via the ProcessContext which will allow them to save simple primitive values and limited length Strings which are local to that node and which are local to that processor only.

Issue Links

• blocks: NIFI-619 update MonitorActivity processor to be cluster friendly
• incorporates: NIFI-1223 TestGetHTTP fails often attempting to delete content of conf directory
• relates to: NIFI-1339 Framework calls onPropertyModified for each property each time NiFi is started