convenience methods for node

pkg/graph/graph.go

@@ -29,22 +29,25 @@ type Node struct {
 	Records []Record
 }
 
-// Added returns the time a node was added to the database.
-func (n *Node) Added() (time.Time, bool) {
-	for _, rec := range n.Records {
-		if rec.Kind == Addition {
-			return rec.Timestamp, true
-		}
-	}
-	return time.Time{}, false
-}
-
 // Record contains the timestamp of a node update.
 type Record struct {
 	Kind      int // either [Addition], [Promotion] or [Demotion]
 	Timestamp time.Time
 }
 
+func (n *Node) Addition() (time.Time, bool)  { return n.find(Addition) }
+func (n *Node) Promotion() (time.Time, bool) { return n.find(Promotion) }
+func (n *Node) Demotion() (time.Time, bool)  { return n.find(Demotion) }
+
+func (n *Node) find(kind int) (time.Time, bool) {
+	for _, record := range n.Records {
+		if record.Kind == kind {
+			return record.Timestamp, true
+		}
+	}
+	return time.Time{}, false
+}
+
 // Delta represents updates to apply to a Node.
 // Add and Remove contain node IDs to add to or remove from the node’s relationships (e.g., follow list).
 type Delta struct {

pkg/pipe/engine.go

@@ -135,7 +135,7 @@ func arbiterScan(ctx context.Context, config ArbiterConfig, db redb.RedisDB, sen
 
 			case graph.StatusInactive:
 				// inactive --> active
-				added, found := node.Added()
+				added, found := node.Addition()
 				if !found {
 					return promoted, demoted, fmt.Errorf("node %s doesn't have an addition record", node.ID)
 				}