Don't change the current state when checkpointing - #325
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jdewar wants to merge 1 commit into
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When checkpointing I don't believe we want to change the state. This usually plays out fine because after a checkpoint when catching_up (which is probably the most common non-:subscribed state), it immediately sets the state back to catching_up when it sees that it's behind. However, persisting event position has nothing to do with state transition, and this feels like a copy-paste mistake.
I don't have an idea what a test for this would look like; the situation we ran into was a subscription getting stuck in a state that would stop event processing. It's several months back at this point so the details have been lost, but we had gone through a number of eventstore tweaks in order to make a massive import of data go fast: we increased checkpoint_threshold > 1 for projectors and we added event selectors, while we were also at the mercy of some database networking issues via our database provider.