Missing (expired) FailedMessage documents cause ServiceControl to crash when trying to dispatch external integration events #425
Description
From desk case 7643
Symptoms
If the ServiceControl has been stopped for a period of time greater than the period specified in the "HoursToKeepMessagesBeforeExpiring" setting it is possible on restart that the document expiry process will remove FailedMessage document that are referenced by messages yet to be processed by the external integration dispatching. This results in a NullReferenceException being thrown and ServiceControl crashing due to a circuit breaker. Subsequent restarts will also fail.
In ServiceControl 1.3.0 the external integration feature would just silently stop working without causing ServiceControl to crash.
Who's affected
- Users of ServiceControl 1.3.0, 1.4.0 and 1.4.1