added changes according to brendan's recommandations

pkg/gateway/changefeed.go

@@ -26,17 +26,13 @@ func (g *gateway) updateFromIterator(ctx context.Context, ticker *time.Ticker, g
 
 	for {
 		docs, err := gwIterator.Next(ctx, -1)
-		successful := true
 
 		for ; docs != nil && err == nil; docs, err = gwIterator.Next(ctx, -1) {
 			g.updateGateways(docs.GatewayDocuments)
 		}
 		if err != nil {
-			successful = false
 			g.log.Error(err)
-		}
-
-		if successful {
+		} else {
 			g.lastChangefeed.Store(time.Now())
 		}
 

pkg/gateway/gateway.go

@@ -209,6 +209,8 @@ func (g *gateway) Run(ctx context.Context, done chan<- struct{}) {
 }
 
 func (g *gateway) updateGateway(doc *api.GatewayDocument) {
+	g.mu.Lock()
+	defer g.mu.Unlock()
 
 	if doc.Gateway.Deleting {
 		// https://docs.microsoft.com/en-us/azure/cosmos-db/change-feed-design-patterns#deletes
@@ -219,8 +221,6 @@ func (g *gateway) updateGateway(doc *api.GatewayDocument) {
 }
 
 func (g *gateway) updateGateways(docs []*api.GatewayDocument) {
-	g.mu.Lock()
-	defer g.mu.Unlock()
 	for _, doc := range docs {
 		g.updateGateway(doc)
 	}