chore: Add showcase tests for closing a client

showcase/gapic-showcase/src/test/java/com/google/showcase/v1beta1/it/ITClientShutdown.java

@@ -75,15 +75,15 @@ public void testHttpJson_rpcInvoked_closeClient() throws Exception {
   }
 
   // This test is to ensure that the client is able to close + terminate any resources
-  // once a response has been received. Set a timeout for this test to be 5s as it should
-  // only take 2s to receive a response. The extra 3s is leeway for the client to be able to be
-  // close properly.
-  @Test(timeout = 5000L)
+  // once a response has been received. Set a max test duration of 15s to ensure that
+  // the test does not continue on forever.
+  @Test(timeout = 15000L)
   public void testGrpc_rpcInvokedWithLargeTimeout_closeClientOnceResponseReceived()
       throws Exception {
     // Set the maxAttempts to 1 to ensure there are no retries scheduled. The single RPC
     // invocation should time out in 15s, but the client will receive a response in 2s.
-    // Any outstanding tasks (timeout tasks) will be cancelled so the client can terminate.
+    // Any outstanding tasks (timeout tasks) should be cancelled once a response has been
+    // received so the client can properly terminate.
     RetrySettings defaultRetrySettings =
         RetrySettings.newBuilder()
             .setInitialRpcTimeout(Duration.ofMillis(15000L))
@@ -101,25 +101,35 @@ public void testGrpc_rpcInvokedWithLargeTimeout_closeClientOnceResponseReceived(
             .setResponseDelay(com.google.protobuf.Duration.newBuilder().setSeconds(2).build())
             .build();
 
+    long start = System.currentTimeMillis();
     BlockResponse response = grpcClient.block(blockRequest);
     Truth.assertThat(response.getContent()).isEqualTo("gRPCBlockContent_2sDelay");
-
     grpcClient.close();
-    grpcClient.awaitTermination(TestClientInitializer.AWAIT_TERMINATION_SECONDS, TimeUnit.SECONDS);
+    // Loop until the client has terminated successfully
+    // Future enhancement: Use awaitility instead of busy waiting
+    while (!grpcClient.isTerminated()) ;
+    long end = System.currentTimeMillis();
     Truth.assertThat(grpcClient.isShutdown()).isTrue();
     Truth.assertThat(grpcClient.isTerminated()).isTrue();
+
+    // Check the termination time. If all the tasks/ resources are closed successfully,
+    // the termination time should only take about 2s (time to receive a response) + time
+    // to close the client. Check that this takes less than 5s (2s request time + 3s
+    // buffer time).
+    long terminationTime = end - start;
+    Truth.assertThat(terminationTime).isLessThan(5000L);
   }
 
   // This test is to ensure that the client is able to close + terminate any resources
-  // once a response has been received. Set a timeout for this test to be 5s as it should
-  // only take 2s to receive a response. The extra 3s is leeway for the client to be able to be
-  // close properly.
-  @Test(timeout = 5000L)
+  // once a response has been received. Set a max test duration of 15s to ensure that
+  // the test does not continue on forever.
+  @Test(timeout = 15000L)
   public void testHttpJson_rpcInvokedWithLargeTimeout_closeClientOnceResponseReceived()
       throws Exception {
     // Set the maxAttempts to 1 to ensure there are no retries scheduled. The single RPC
     // invocation should time out in 15s, but the client will receive a response in 2s.
-    // Any outstanding tasks (timeout tasks) will be cancelled so the client can terminate.
+    // Any outstanding tasks (timeout tasks) should be cancelled once a response has been
+    // received so the client can properly terminate.
     RetrySettings defaultRetrySettings =
         RetrySettings.newBuilder()
             .setInitialRpcTimeout(Duration.ofMillis(15000L))
@@ -137,13 +147,24 @@ public void testHttpJson_rpcInvokedWithLargeTimeout_closeClientOnceResponseRecei
             .setResponseDelay(com.google.protobuf.Duration.newBuilder().setSeconds(2).build())
             .build();
 
+    long start = System.currentTimeMillis();
     BlockResponse response = httpjsonClient.block(blockRequest);
     Truth.assertThat(response.getContent()).isEqualTo("httpjsonBlockContent_2sDelay");
-
     httpjsonClient.close();
-    httpjsonClient.awaitTermination(
-        TestClientInitializer.AWAIT_TERMINATION_SECONDS, TimeUnit.SECONDS);
+    // Loop until the client has terminated successfully
+    // Future enhancement: Use awaitility instead of busy waiting
+    while (!httpjsonClient.isTerminated()) {
+      Thread.sleep(1000L);
+    }
+    long end = System.currentTimeMillis();
     Truth.assertThat(httpjsonClient.isShutdown()).isTrue();
     Truth.assertThat(httpjsonClient.isTerminated()).isTrue();
+
+    // Check the termination time. If all the tasks/ resources are closed successfully,
+    // the termination time should only take about 2s (time to receive a response) + time
+    // to close the client. Check that this takes less than 5s (2s request time + 3s
+    // buffer time).
+    long terminationTime = end - start;
+    Truth.assertThat(terminationTime).isLessThan(5000L);
   }
 }