From bc1d135da2fce6391c4a617266b5d7d6042837d9 Mon Sep 17 00:00:00 2001
From: "Eduardo J. Ortega U." <5791035+ejortegau@users.noreply.github.com>
Date: Mon, 3 Feb 2025 15:46:14 +0100
Subject: [PATCH] Add logging to debug CI failures

Signed-off-by: Eduardo J. Ortega U. <5791035+ejortegau@users.noreply.github.com>
---
 go/test/endtoend/cluster/cluster_process.go | 2 ++
 go/vt/discovery/healthcheck.go              | 3 ++-
 go/vt/discovery/topology_watcher.go         | 7 +++++++
 3 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/go/test/endtoend/cluster/cluster_process.go b/go/test/endtoend/cluster/cluster_process.go
index ed61f7fd0c9..61d7145db86 100644
--- a/go/test/endtoend/cluster/cluster_process.go
+++ b/go/test/endtoend/cluster/cluster_process.go
@@ -513,6 +513,8 @@ func (cluster *LocalProcessCluster) AddShard(keyspaceName string, shardName stri
 	for _, proc := range mysqlctlProcessList {
 		if err := proc.Wait(); err != nil {
 			log.Errorf("unable to start mysql process %v: %v", proc, err)
+			log.Errorf("Stdout: %s", proc.Stdout)
+			log.Errorf("Stderr: %s", proc.Stderr)
 			return nil, err
 		}
 	}
diff --git a/go/vt/discovery/healthcheck.go b/go/vt/discovery/healthcheck.go
index 2f270bd7518..d8e16f03d81 100644
--- a/go/vt/discovery/healthcheck.go
+++ b/go/vt/discovery/healthcheck.go
@@ -395,6 +395,7 @@ func NewHealthCheck(ctx context.Context, retryDelay, healthCheckTimeout time.Dur
 func (hc *HealthCheckImpl) AddTablet(tablet *topodata.Tablet) {
 	// check whether grpc port is present on tablet, if not return
 	if tablet.PortMap["grpc"] == 0 {
+		log.Infof("grpc port missing for tablet, not adding: %v", tablet.PortMap)
 		return
 	}
 
@@ -831,7 +832,7 @@ func (hc *HealthCheckImpl) waitForTablets(ctx context.Context, targets []*query.
 			timer.Stop()
 			for _, target := range targets {
 				if target != nil {
-					log.Infof("couldn't find tablets for target: %v", target)
+					log.Infof("couldn't find tablets for target: %v - Require serving is %+v", target, requireServing)
 				}
 			}
 			return ctx.Err()
diff --git a/go/vt/discovery/topology_watcher.go b/go/vt/discovery/topology_watcher.go
index d1e358e1aa5..8df02d4fc27 100644
--- a/go/vt/discovery/topology_watcher.go
+++ b/go/vt/discovery/topology_watcher.go
@@ -163,6 +163,7 @@ func (tw *TopologyWatcher) loadTablets() {
 	defer tw.mu.Unlock()
 
 	for _, tInfo := range tabletInfos {
+		log.Infof("Got tabletInfo for %+v, isInServingGraph is %v", tInfo, tInfo.IsInServingGraph())
 		aliasStr := topoproto.TabletAliasString(tInfo.Alias)
 		tabletAliasStrs = append(tabletAliasStrs, aliasStr)
 
@@ -170,6 +171,7 @@ func (tw *TopologyWatcher) loadTablets() {
 			// We already have a tabletInfo for this and the flag tells us to not refresh.
 			if val, ok := tw.tablets[aliasStr]; ok {
 				newTablets[aliasStr] = val
+				log.Infof("Tablet Info already known and not refreshing for %+v", *tInfo)
 				continue
 			}
 		}
@@ -192,17 +194,21 @@ func (tw *TopologyWatcher) loadTablets() {
 		}
 	}
 
+	log.Infof("New tablets %+v", newTablets)
 	for alias, newVal := range newTablets {
 		if tw.tabletFilter != nil && !tw.tabletFilter.IsIncluded(newVal.tablet) {
+			log.Infof("Tablet %s filtered out", alias)
 			continue
 		}
 
 		// Trust the alias from topo and add it if it doesn't exist.
 		if val, ok := tw.tablets[alias]; ok {
+			log.Infof("Tablet %s already in tw.tablets", alias)
 			// check if the host and port have changed. If yes, replace tablet.
 			oldKey := TabletToMapKey(val.tablet)
 			newKey := TabletToMapKey(newVal.tablet)
 			if oldKey != newKey {
+				log.Infof("Tablet key mismatch: old %s new %s, replacing in healthcheck", oldKey, newKey)
 				// This is the case where the same tablet alias is now reporting
 				// a different address (host:port) key.
 				tw.healthcheck.ReplaceTablet(val.tablet, newVal.tablet)
@@ -210,6 +216,7 @@ func (tw *TopologyWatcher) loadTablets() {
 			}
 		} else {
 			// This is a new tablet record, let's add it to the HealthCheck.
+			log.Infof("Tablet %s not in tw.tablets, adding to healthcheck", alias)
 			tw.healthcheck.AddTablet(newVal.tablet)
 			topologyWatcherOperations.Add(topologyWatcherOpAddTablet, 1)
 		}