Enforce sequential processing of session events #4493
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NOTE: Apparent double execution of lock function needs to be investigated.
ruslandoga
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ruslandoga
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aerosol
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Changes
This PR enforces sequential processing of events for the same session. Currently, when two events for the same session are processed concurrently, it's possible that session lookup will either turn up empty (initial event) or return the same previous session state for two concurrently processed events. This in turn can result in inconsistent session entries (like, for instance, two session entries for the same session_id). More detailed example race scenario this fix addresses is described at https://github.com/plausible/analytics/pull/4493/files#diff-16bb729e90786448aef27f15fce06e9d977d947389e91fdc24c0ea6760c290f6R78-R99.
TODO
with_lock!, end at the very beginning of lock function body)Tests