more platform

catalog/projection.go

@@ -36,6 +36,7 @@ import (
 	"encoding/json"
 
 	"git.k6n.net/mats/platform/money"
+	"git.k6n.net/mats/platform/projection"
 )
 
 // Projection is the published, versioned catalog entry that commerce modules
@@ -82,10 +83,10 @@ import (
 // the JSON token. The on-disk snapshot binary header/record layout is
 // unchanged \u2014 only the per-blob JSON payload gains a key.
 type Projection struct {
-	ItemID uint32 `json:"item_id,omitempty"`
-	ID     string `json:"id"`
-	SKU    string `json:"sku"`
-	Title  string `json:"title,omitempty"`
+	ItemID      uint32      `json:"item_id,omitempty"`
+	ID          string      `json:"id"`
+	SKU         string      `json:"sku"`
+	Title       string      `json:"title,omitempty"`
 	PriceIncVat money.Cents `json:"price_inc_vat"`
 	Currency    string      `json:"currency,omitempty"`
 	// TaxClass uses a string identifier (see platform/tax class constants).
@@ -154,7 +155,9 @@ func Decode(raw []byte) (Projection, error) {
 // catalog.projection_published carries two channels distinguished only by
 // event.Event.Meta. The producer (slask-finder writeradmin) sets these keys and
 // the consumer (ProjectionStore, consumer.go) reads them — one definition so the
-// two never drift. See docs/catalog-projection.md.
+// two never drift. The framing itself is domain-neutral and lives in
+// platform/projection; catalog re-exports the constants so the producer/consumer
+// keep their catalog.* names. See docs/catalog-projection.md.
 //
 //   - A FULL SNAPSHOT is a framed begin → chunk* → end stream, all tagged with one
 //     MetaEpoch. begin/end carry MetaCount (total projections) for completeness
@@ -162,13 +165,13 @@ func Decode(raw []byte) (Projection, error) {
 //   - A DELTA has NO MetaSnapshotPhase key, and MetaEpoch names the snapshot base
 //     it builds on (consumers ignore a delta older than the base they hold).
 const (
-	MetaSnapshotPhase = "snapshot" // begin|chunk|end; absent ⇒ delta
-	MetaEpoch         = "epoch"     // int64 (Unix-ms), monotonic across rebuilds
-	MetaSeq           = "seq"       // chunk sequence within a snapshot
-	MetaCount         = "count"     // total projections (begin/end only)
-	MetaTenant        = "tenant"    // namespace tag
+	MetaSnapshotPhase = projection.MetaSnapshotPhase // begin|chunk|end; absent ⇒ delta
+	MetaEpoch         = projection.MetaEpoch         // int64 (Unix-ms), monotonic across rebuilds
+	MetaSeq           = projection.MetaSeq           // chunk sequence within a snapshot
+	MetaCount         = projection.MetaCount         // total projections (begin/end only)
+	MetaTenant        = projection.MetaTenant        // namespace tag
 
-	SnapshotBegin = "begin"
-	SnapshotChunk = "chunk"
-	SnapshotEnd   = "end"
+	SnapshotBegin = projection.SnapshotBegin
+	SnapshotChunk = projection.SnapshotChunk
+	SnapshotEnd   = projection.SnapshotEnd
 )