From 19c8814a70e3357c5f26a861e26693906af16d2a Mon Sep 17 00:00:00 2001
From: Mark Mandel <markmandel@google.com>
Date: Fri, 7 Jun 2019 14:08:06 -0700
Subject: [PATCH] Handle delete events when caching Ready GameServers for
 Allocation (#815)

---
 pkg/gameserverallocations/controller.go      | 28 +++++++++++++++-----
 pkg/gameserverallocations/controller_test.go | 27 +++++++++++++++++++
 2 files changed, 48 insertions(+), 7 deletions(-)

diff --git a/pkg/gameserverallocations/controller.go b/pkg/gameserverallocations/controller.go
index 5bf1824af9..f0ba2b1cc0 100644
--- a/pkg/gameserverallocations/controller.go
+++ b/pkg/gameserverallocations/controller.go
@@ -146,16 +146,30 @@ func NewController(apiServer *apiserver.APIServer,
 			// only interested in if the old / new state was/is Ready
 			oldGs := oldObj.(*stablev1alpha1.GameServer)
 			newGs := newObj.(*stablev1alpha1.GameServer)
-			if oldGs.Status.State == stablev1alpha1.GameServerStateReady || newGs.Status.State == stablev1alpha1.GameServerStateReady {
-				if key, ok := c.getKey(newGs); ok {
-					if newGs.Status.State == stablev1alpha1.GameServerStateReady {
-						c.readyGameServers.Store(key, newGs)
-					} else {
-						c.readyGameServers.Delete(key)
-					}
+			key, ok := c.getKey(newGs)
+			if !ok {
+				return
+			}
+			if newGs.IsBeingDeleted() {
+				c.readyGameServers.Delete(key)
+			} else if oldGs.Status.State == stablev1alpha1.GameServerStateReady || newGs.Status.State == stablev1alpha1.GameServerStateReady {
+				if newGs.Status.State == stablev1alpha1.GameServerStateReady {
+					c.readyGameServers.Store(key, newGs)
+				} else {
+					c.readyGameServers.Delete(key)
 				}
 			}
 		},
+		DeleteFunc: func(obj interface{}) {
+			gs, ok := obj.(*stablev1alpha1.GameServer)
+			if !ok {
+				return
+			}
+			var key string
+			if key, ok = c.getKey(gs); ok {
+				c.readyGameServers.Delete(key)
+			}
+		},
 	})
 
 	return c
diff --git a/pkg/gameserverallocations/controller_test.go b/pkg/gameserverallocations/controller_test.go
index 73a9989263..ccbb348dfc 100644
--- a/pkg/gameserverallocations/controller_test.go
+++ b/pkg/gameserverallocations/controller_test.go
@@ -695,6 +695,33 @@ func TestControllerRunCacheSync(t *testing.T) {
 	watch.Modify(gs.DeepCopy())
 
 	assertCacheEntries(0)
+
+	// add back in ready gameserver
+	gs.Status.State = stablev1alpha1.GameServerStateReady
+	watch.Modify(gs.DeepCopy())
+	assertCacheEntries(0)
+	gs.Status.State = stablev1alpha1.GameServerStateReady
+	watch.Modify(gs.DeepCopy())
+	assertCacheEntries(1)
+
+	// update with deletion timestamp
+	n := metav1.Now()
+	deletedCopy := gs.DeepCopy()
+	deletedCopy.ObjectMeta.DeletionTimestamp = &n
+	watch.Modify(deletedCopy)
+	assertCacheEntries(0)
+
+	// add back in ready gameserver
+	gs.Status.State = stablev1alpha1.GameServerStateReady
+	watch.Modify(gs.DeepCopy())
+	assertCacheEntries(0)
+	gs.Status.State = stablev1alpha1.GameServerStateReady
+	watch.Modify(gs.DeepCopy())
+	assertCacheEntries(1)
+
+	// now actually delete it
+	watch.Delete(gs.DeepCopy())
+	assertCacheEntries(0)
 }
 
 func TestGetRandomlySelectedGS(t *testing.T) {