Test for making backoff timer expiry not make a RLS rpc directly but update the parent LB policy with picker after deleting backoff cache entry.

Author: kannanjgithub

rls/src/test/java/io/grpc/rls/CachingRlsLbClientTest.java

@@ -160,8 +160,9 @@ public void uncaughtException(Thread t, Throwable e) {
           fakeClock.getScheduledExecutorService());
   private final ChildLoadBalancingPolicy childLbPolicy =
       new ChildLoadBalancingPolicy("target", Collections.<String, Object>emptyMap(), lbProvider);
+  private final FakeHelper fakeHelper = new FakeHelper();
   private final Helper helper =
-      mock(Helper.class, delegatesTo(new FakeHelper()));
+      mock(Helper.class, delegatesTo(fakeHelper));
   private final FakeThrottler fakeThrottler = new FakeThrottler();
   private final LbPolicyConfiguration lbPolicyConfiguration =
       new LbPolicyConfiguration(ROUTE_LOOKUP_CONFIG, null, childLbPolicy);
@@ -325,29 +326,14 @@ public void get_throttledAndRecover() throws Exception {
 
     assertThat(resp.hasError()).isTrue();
 
-    fakeClock.forwardTime(10, TimeUnit.MILLISECONDS);
-    // initially backed off entry is backed off again
-    verify(evictionListener)
-        .onEviction(eq(routeLookupRequest), any(CacheEntry.class), eq(EvictionType.EXPLICIT));
-
-    resp = getInSyncContext(routeLookupRequest);
-
-    assertThat(resp.hasError()).isTrue();
-
     // let it pass throttler
     fakeThrottler.nextResult = false;
     fakeClock.forwardTime(10, TimeUnit.MILLISECONDS);
-
-    resp = getInSyncContext(routeLookupRequest);
-
-    assertThat(resp.isPending()).isTrue();
-
-    // server responses
-    fakeClock.forwardTime(SERVER_LATENCY_MILLIS, TimeUnit.MILLISECONDS);
-
-    resp = getInSyncContext(routeLookupRequest);
-
-    assertThat(resp.hasData()).isTrue();
+    // Backoff entry evicted from cache.
+    verify(evictionListener)
+        .onEviction(eq(routeLookupRequest), any(CacheEntry.class), eq(EvictionType.EXPLICIT));
+    // Assert that Rls LB policy picker was updated.
+    assertThat(fakeHelper.lastPicker.toString()).isEqualTo("RlsPicker{target=service1}");
   }
 
   @Test
@@ -894,6 +880,7 @@ public void run() {
 
   private final class FakeHelper extends Helper {
 
+    SubchannelPicker lastPicker;
     @Override
     public ManagedChannelBuilder<?> createResolvingOobChannelBuilder(
         String target, ChannelCredentials creds) {
@@ -948,7 +935,7 @@ public ManagedChannel createOobChannel(EquivalentAddressGroup eag, String author
     @Override
     public void updateBalancingState(
         @Nonnull ConnectivityState newState, @Nonnull SubchannelPicker newPicker) {
-      // no-op
+      lastPicker = newPicker;
     }
 
     @Override