Bigtable: Add integration test to test nonexistent row handling (#3870)

Author: igorbernstein2

google-cloud-clients/google-cloud-bigtable/src/test/java/com/google/cloud/bigtable/data/v2/it/ReadIT.java

@@ -17,6 +17,9 @@
 
 import static com.google.common.truth.Truth.assertThat;
 
+import com.google.api.core.ApiFuture;
+import com.google.api.core.ApiFutureCallback;
+import com.google.api.core.ApiFutures;
 import com.google.api.core.SettableApiFuture;
 import com.google.api.gax.rpc.ResponseObserver;
 import com.google.api.gax.rpc.StreamController;
@@ -27,11 +30,14 @@
 import com.google.cloud.bigtable.data.v2.models.RowMutation;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Lists;
+import com.google.common.util.concurrent.MoreExecutors;
 import com.google.protobuf.ByteString;
 import java.util.ArrayList;
 import java.util.List;
+import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.ExecutionException;
 import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicBoolean;
 import org.junit.Before;
 import org.junit.ClassRule;
 import org.junit.Test;
@@ -111,6 +117,31 @@ public void read() throws Throwable {
     assertThat(observer.responses).containsExactlyElementsIn(expectedRows);
   }
 
+  @Test
+  public void readSingleNonexistentAsyncCallback() throws Exception {
+    ApiFuture<Row> future = testEnvRule.env().getDataClient()
+        .readRowAsync(testEnvRule.env().getTableName().getTable(), "somenonexistentkey");
+
+    final AtomicBoolean found = new AtomicBoolean();
+    final CountDownLatch latch = new CountDownLatch(1);
+
+    ApiFutures.addCallback(future, new ApiFutureCallback<Row>() {
+      @Override
+      public void onFailure(Throwable t) {
+        latch.countDown();
+      }
+
+      @Override
+      public void onSuccess(Row result) {
+        found.set(true);
+        latch.countDown();
+      }
+    }, MoreExecutors.directExecutor());
+
+    latch.await(1, TimeUnit.MINUTES);
+    assertThat(found.get()).isTrue();
+  }
+
   static class AccumulatingObserver implements ResponseObserver<Row> {
     final List<Row> responses = Lists.newArrayList();
     final SettableApiFuture<Void> completionFuture = SettableApiFuture.create();