[jboss-jira] [JBoss JIRA] (JGRP-1557) SUPERVISOR: protocol to check conditions and perform corrective actions if needed

[Bela Ban (JIRA)]

Bela Ban created JGRP-1557:
------------------------------

             Summary: SUPERVISOR: protocol to check conditions and perform corrective actions if needed
                 Key: JGRP-1557
                 URL: https://issues.jboss.org/browse/JGRP-1557
             Project: JGroups
          Issue Type: Feature Request
            Reporter: Bela Ban
            Assignee: Bela Ban
             Fix For: 3.3


SUPERVISOR is a protocol anywhere in the stack that passes messages up and down by default; it doesn't take part in message processing.
However, it handles events ADD_ASSERTION / REMOVE_ASSERTION, which adds/removes assertions. An assertion is a condition with a name, an interval and an (optional) action. Both conditions and actions can be Runnables, but this needs to be defined later.

When the interval for a condition has elapsed, it is triggered and (if true) it'll invoke the associated action. A condition can be triggered by an interval elapsed or perhaps also when a event is received (e.g. a view change).

Example:
- Condition: check if FD is present in the stack. If it is and fd.isMonitorRunning() == false and fd.getView().size() > 1, then call action fd.startFailureDetection() and log an error message.

The error messages are stored in a bounded list, so the last N error messages can be retrieved, e.g. via probe.sh.

--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see: http://www.atlassian.com/software/jira