`IEventItemProjectionBuilder<TEventItem>` - Inbox Decorator

[mumby0168]

We can make use of another container or maybe an in-memory cache to guarantee that an event won't be processed more than once.

This would use the unique ID of an event this would be saved as soon as the event is provided by the change feed. It can then be checked for every event that we process. There are two implementations of this we can use.

• in-memory
• using another container

We can use the decorator pattern to allow this to be applied.