more flow control

Author: LukeAVanDrie

pkg/epp/flowcontroller/flowcontroller.go

@@ -42,6 +42,11 @@ type flowItem struct {
 	// effectiveTTL is the actual Time-To-Live assigned to this item by the FlowController, considering the request's
 	// preference and controller defaults.
 	effectiveTTL time.Duration
+	// priorityScore represents the dispatch priority of this item. The score's meaning and calculation method are
+	// determined by the IntraFlowDispatchPolicy governing this item's queue, and its type is indicated by
+	// QueueStateReader.PriorityScoreType() of the queue.
+	// Convention: For many scores, a lower numerical value might indicate higher priority.
+	priorityScore float64
 	// queueHandle is the opaque handle returned by the FlowQueue when this item is successfully added to a queue.
 	// It's used by the FlowController to instruct the FlowQueue to remove this specific item.
 	// This is nil until the item is successfully enqueued into a FlowQueue.
@@ -83,6 +88,8 @@ func newFlowItem(req types.FlowControlRequest, spec types.FlowSpecification, eff
 
 // --- Implementation of types.QueueItemAccessor ---
 
+var _ types.QueueItemAccessor = &flowItem{} // Compile-time validation
+
 func (fi *flowItem) EnqueueTime() time.Time {
 	return fi.enqueueTime
 }
@@ -107,6 +114,18 @@ func (fi *flowItem) OriginalRequest() types.FlowControlRequest {
 	return fi.originalRequest
 }
 
+func (fi *flowItem) PriorityScore() float64 {
+	return fi.priorityScore
+}
+
+func (fi *flowItem) Handle() types.QueueItemHandle {
+	return fi.queueHandle
+}
+
+func (fi *flowItem) SetHandle(handle types.QueueItemHandle) {
+	fi.queueHandle = handle
+}
+
 // --- Lifecycle Management Methods (called by FlowController) ---
 
 // setQueueDetails is called by the FlowController *after* an item has been