Allow Projections Recreation (Same named projections) #517
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When deleting a projection, ensure that a $ProjectionDeleted event is written to $projections-$all This event allows us to know which projections are actually alive. When creating a projection, we check for the existence of a $projections-[projection-name] stream. If this stream exists, we grab the last known event number, increment it by one and that would be the version for the projection. Checkpoint stream for projection should be deleted when the user requests for it to. Should not hard delete the checkpoint stream (there might be a case where the user wants to recreate the projection) When loading the checkpoint, there might be a case where there are no events as the stream has been deleted. However, if we attempt to write to that checkpoint stream and tell it that we expect the stream to not exist (Expected Version: -1), it will fail. We need to cater for situations where the checkpoint stream is being reused for instances where the projection gets recreated.
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Allow recreation of a deleted projection
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This PR fixes an issue where deleted projections cannot be recreated.
In addition includes the deletion of the projections checkpoint stream.