Track projectors state (replaying/activating/active) in the database#472
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erikrozendaal merged 15 commits intomasterfrom Jun 20, 2025
Merged
Track projectors state (replaying/activating/active) in the database#472erikrozendaal merged 15 commits intomasterfrom
erikrozendaal merged 15 commits intomasterfrom
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New is a bit confusing, since normally it refers to the current version of the running system. Only when running view schema migrations is new vs old version relevant.
lvonk
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Jun 11, 2025
lib/sequent/core/transactions/read_only_active_record_transaction_provider.rb
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| process_events | ||
| end | ||
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| def replay_events(events) |
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Maybe this should be in an EventReplayer or so?
lvonk
reviewed
Jun 11, 2025
During activation the last existing events are replayed before the projector is marked active. Block new events since they will not be picked up by the replay process.
Use `EventStore#replay_events_from_cursor` instead.
As long as the projector_states table is empty it is assumed the current Sequent configuration is correct. This allows easier unit testing (since there is no need to activate a configuration every time it changes in the test) and allows for backwards compatibility with the current deployment process (using online and offline migration).
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The event publisher and projector check the current state when processing events to:
NewerProjectorIsActiveErrorerrors.This PR is another step towards allowing rolling upgrades, where version N and version N+1 code is running concurrently during an upgrade, without affecting any users.
TODO
activate_current_configuration!