Event Sourcing + CQRS

Commands mutate in-memory grain state; one ConfirmEvents transaction persists the batch; lists and finished instances read a materialized projection, never the event log

Event Sourcing + CQRS Commands mutate in-memory grain state; one ConfirmEvents transaction persists the batch; lists and finished instances read a materialized projection, never the event log 01 / Commands 02 / Write model 03 / Persist 04 / Read model 05 / Queries API / Admin UI · start, complete, signal · 01 / Commands · command API / Admin UI start, complete, signal command WorkflowInstance · in-memory state · 02 / Write model · JournaledGrain WorkflowInstance in-memory state JournaledGrain Event log · FleanCommandDbContext · 03 / Persist · append-only Event log FleanCommandDbContext append-only State projection · WorkflowInstanceProjector · 03 / Persist · async, from the journal State projection WorkflowInstanceProjector async, from the journal Read model · denormalized snapshot · 04 / Read model · materialized Read model denormalized snapshot materialized FleanQueryDbContext · NoTracking reads · 04 / Read model · replica optional FleanQueryDbContext NoTracking reads replica optional Admin UI / GET state · /instances/{id}/state · 05 / Queries · query Admin UI / GET state /instances/{id}/state query command ConfirmEvents 1 transaction InstanceAdvanced upsert read query Legend primary data data store data flow

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