From 575b99840aeb3e6be0aaeeb6e22ccd5eafc804e0 Mon Sep 17 00:00:00 2001
From: David Zhao <david@davidzhao.com>
Date: Sun, 10 Oct 2021 22:25:29 -0700
Subject: [PATCH] Fixed handling of multiple nodes in region-aware routing

---
 pkg/routing/selector/regionaware.go      |  3 +--
 pkg/routing/selector/regionaware_test.go | 18 ++++++++++++++++++
 pkg/service/server.go                    |  3 +++
 3 files changed, 22 insertions(+), 2 deletions(-)

diff --git a/pkg/routing/selector/regionaware.go b/pkg/routing/selector/regionaware.go
index 664a2eb50..97680501a 100644
--- a/pkg/routing/selector/regionaware.go
+++ b/pkg/routing/selector/regionaware.go
@@ -64,12 +64,11 @@ func (s *RegionAwareSelector) SelectNode(nodes []*livekit.Node, room *livekit.Ro
 
 	// find nodes nearest to current region
 	var nearestNodes []*livekit.Node
-	nearestRegion := s.CurrentRegion
+	nearestRegion := ""
 	minDist := math.MaxFloat64
 	for _, node := range nodes {
 		if node.Region == nearestRegion {
 			nearestNodes = append(nearestNodes, node)
-			minDist = 0
 			continue
 		}
 		if dist, ok := s.regionDistances[node.Region]; ok {
diff --git a/pkg/routing/selector/regionaware_test.go b/pkg/routing/selector/regionaware_test.go
index f5372dacb..29a92b476 100644
--- a/pkg/routing/selector/regionaware_test.go
+++ b/pkg/routing/selector/regionaware_test.go
@@ -97,6 +97,24 @@ func TestRegionAwareRouting(t *testing.T) {
 		require.Equal(t, expectedNode, node)
 	})
 
+	t.Run("handles multiple nodes in same region", func(t *testing.T) {
+		expectedNode := newTestNodeInRegion(regionWest, true)
+		nodes := []*livekit.Node{
+			newTestNodeInRegion(regionSeattle, false),
+			newTestNodeInRegion(regionEast, true),
+			newTestNodeInRegion(regionEast, true),
+			expectedNode,
+			expectedNode,
+		}
+		s, err := selector.NewRegionAwareSelector(regionSeattle, rc)
+		require.NoError(t, err)
+		s.SysloadLimit = loadLimit
+
+		node, err := s.SelectNode(nodes, nil)
+		require.NoError(t, err)
+		require.Equal(t, expectedNode, node)
+	})
+
 	t.Run("functions when current region is full", func(t *testing.T) {
 		nodes := []*livekit.Node{
 			newTestNodeInRegion(regionWest, true),
diff --git a/pkg/service/server.go b/pkg/service/server.go
index 272338974..a7febb778 100644
--- a/pkg/service/server.go
+++ b/pkg/service/server.go
@@ -173,6 +173,9 @@ func (s *LivekitServer) Start() error {
 		if s.config.PrometheusPort != 0 {
 			values = append(values, "portPrometheus", s.config.PrometheusPort)
 		}
+		if s.config.Region != "" {
+			values = append(values, "region", s.config.Region)
+		}
 		logger.Infow("starting LiveKit server", values...)
 		if err := s.httpServer.Serve(ln); err != http.ErrServerClosed {
 			logger.Errorw("could not start server", err)