From 896f4dd76a670824d79feedd8ec98b8ac646bca7 Mon Sep 17 00:00:00 2001
From: Alexander Yastrebov <alexander.yastrebov@zalando.de>
Date: Mon, 17 Jun 2024 16:31:27 +0200
Subject: [PATCH] routing: log route update id (#3112)

Add and log route update counter to observe delay between receiving and
applying routes.

Signed-off-by: Alexander Yastrebov <alexander.yastrebov@zalando.de>
---
 routing/datasource.go | 6 ++++--
 routing/routing.go    | 2 +-
 2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/routing/datasource.go b/routing/datasource.go
index 36f8b7ce91..e18f1875c3 100644
--- a/routing/datasource.go
+++ b/routing/datasource.go
@@ -511,6 +511,7 @@ func processRouteDefs(o Options, fr filters.Registry, defs []*eskip.Route) (rout
 }
 
 type routeTable struct {
+	id            int
 	m             *matcher
 	once          sync.Once
 	routes        []*Route // only used for closing
@@ -543,10 +544,10 @@ func receiveRouteMatcher(o Options, out chan<- *routeTable, quit <-chan struct{}
 		updatesRelay <-chan []*eskip.Route
 	)
 	updatesRelay = updates
-	for {
+	for id := 1; ; id++ {
 		select {
 		case defs := <-updatesRelay:
-			o.Log.Info("route settings received")
+			o.Log.Infof("route settings received, id: %d", id)
 
 			for i := range o.PreProcessors {
 				defs = o.PreProcessors[i].Do(defs)
@@ -582,6 +583,7 @@ func receiveRouteMatcher(o Options, out chan<- *routeTable, quit <-chan struct{}
 			})
 
 			rt = &routeTable{
+				id:            id,
 				m:             m,
 				routes:        routes,
 				validRoutes:   validRoutes,
diff --git a/routing/routing.go b/routing/routing.go
index efdb746305..21c21d4772 100644
--- a/routing/routing.go
+++ b/routing/routing.go
@@ -353,7 +353,7 @@ func (r *Routing) startReceivingUpdates(o Options) {
 						r.firstLoadSignaled = true
 					}
 				}
-				r.log.Info("route settings applied")
+				r.log.Infof("route settings applied, id: %d", rt.id)
 				if r.metrics != nil { // existing codebases might not supply metrics instance
 					r.metrics.UpdateGauge("routes.total", float64(len(rt.validRoutes)))
 					r.metrics.UpdateGauge("routes.updated_timestamp", float64(rt.created.Unix()))