feat: gamemaster

gamemaster/internal/ports/streamoffsetstore.go

@@ -0,0 +1,25 @@
+package ports
+
+import "context"
+
+//go:generate go run go.uber.org/mock/mockgen -destination=../adapters/mocks/mock_streamoffsetstore.go -package=mocks galaxy/gamemaster/internal/ports StreamOffsetStore
+
+// StreamOffsetStore persists the last successfully processed Redis
+// Stream entry id per consumer label. Workers call Load on startup to
+// resume from the persisted offset and Save after every successful
+// message handling so the next iteration advances past the
+// just-processed entry. The label is the short logical identifier of
+// the consumer (e.g., `health_events`), not the full stream name; it
+// stays stable when the underlying stream key is renamed.
+type StreamOffsetStore interface {
+	// Load returns the last processed entry id for the consumer
+	// labelled stream when one is stored. The boolean return reports
+	// whether a value was present; implementations must not return an
+	// error for a missing key.
+	Load(ctx context.Context, stream string) (entryID string, found bool, err error)
+
+	// Save stores entryID as the new last processed offset for the
+	// consumer labelled stream. Implementations overwrite any previous
+	// value unconditionally.
+	Save(ctx context.Context, stream, entryID string) error
+}