README
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Filtered feed reads
Read the global event feed filtered by an indexed axis — event type, stream id,
or stream category — with EventStore.LoadEventsFromPositionFiltered. The predicate
is pushed down to storage, so a narrow read touches only matching rows instead of
loading the whole feed and filtering in Go.
This is an introspection primitive: audit browsers, migration/backfill scanners, and diagnostics. It is not an application read path — for queries over unindexed data (a tenant in metadata, a payload field) or for application reads, project a read model instead.
Run
go run ./examples/feed-filter
No database required — it uses the in-memory adapter.
What to look for
FeedFilter{EventTypes: ...}— every event of a type, across all streams (uses theevent_typeindex on PostgreSQL).FeedFilter{Category: "order"}— the wholeorder-*feed, escaped so it can't over-match adjacent categories.- Axes AND-compose; a multi-valued axis (e.g. several
EventTypes) is an OR set. - An empty
FeedFilteris identical toLoadEventsFromPosition.
Results keep the ordering, limit, exclusivity, and gapless safe-watermark
guarantees of the unfiltered read. Only the in-memory and PostgreSQL adapters
implement it; another adapter returns ErrFilteredFeedNotSupported.
Documentation
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Overview ¶
Package main demonstrates filtered feed reads — reading the global event feed by an INDEXED axis for introspection.
EventStore.LoadEventsFromPositionFiltered filters the load-from-position read by event type, stream id, and/or stream category, pushing the predicate down to storage instead of loading the whole feed and filtering in Go. It is meant for introspection tooling — audit browsers, migration/backfill scanners, diagnostics — not application read paths (project a read model for those).
Runs on the in-memory adapter, so it needs NO database:
go run ./examples/feed-filter
Source Files