interop-testing: Modernize stress test channel creation

OverrideAuthority() is the modern alternative to rewriting the
InetAddress, and can also work if we change the channel creation to use
target strings instead. We can use test CAs now without resorting to the
Netty-specific APIs. After this change, only 4 classes in
interop-testing depend on Netty.

interop-testing/src/main/java/io/grpc/testing/integration/StressTestClient.java

@@ -32,24 +32,22 @@ import com.google.common.util.concurrent.Futures;
 import com.google.common.util.concurrent.ListenableFuture;
 import com.google.common.util.concurrent.ListeningExecutorService;
 import com.google.common.util.concurrent.MoreExecutors;
+import io.grpc.ChannelCredentials;
+import io.grpc.Grpc;
+import io.grpc.InsecureChannelCredentials;
 import io.grpc.ManagedChannel;
 import io.grpc.ManagedChannelBuilder;
 import io.grpc.Server;
 import io.grpc.ServerBuilder;
 import io.grpc.Status;
 import io.grpc.StatusException;
-import io.grpc.netty.GrpcSslContexts;
+import io.grpc.TlsChannelCredentials;
-import io.grpc.netty.NegotiationType;
-import io.grpc.netty.NettyChannelBuilder;
 import io.grpc.stub.StreamObserver;
 import io.grpc.testing.TlsTesting;
-import io.netty.handler.ssl.SslContext;
 import java.io.IOException;
-import java.net.InetAddress;
 import java.net.InetSocketAddress;
 import java.net.URI;
 import java.net.URISyntaxException;
-import java.net.UnknownHostException;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.Iterator;
@@ -296,19 +294,9 @@ public class StressTestClient {
     List<InetSocketAddress> addresses = new ArrayList<>();
 
     for (List<String> namePort : parseCommaSeparatedTuples(addressesStr)) {
-      InetAddress address;
       String name = namePort.get(0);
       int port = Integer.valueOf(namePort.get(1));
-      try {
+      addresses.add(new InetSocketAddress(name, port));
-        address = InetAddress.getByName(name);
-        if (serverHostOverride != null) {
-          // Force the hostname to match the cert the server uses.
-          address = InetAddress.getByAddress(serverHostOverride, address.getAddress());
-        }
-      } catch (UnknownHostException ex) {
-        throw new RuntimeException(ex);
-      }
-      addresses.add(new InetSocketAddress(address, port));
     }
 
     return addresses;
@@ -341,19 +329,28 @@ public class StressTestClient {
   }
 
   private ManagedChannel createChannel(InetSocketAddress address) {
-    SslContext sslContext = null;
+    ChannelCredentials channelCredentials;
-    if (useTestCa) {
+    if (useTls) {
-      try {
+      if (useTestCa) {
-        sslContext = GrpcSslContexts.forClient().trustManager(
+        try {
-            TlsTesting.loadCert("ca.pem")).build();
+          channelCredentials = TlsChannelCredentials.newBuilder()
-      } catch (Exception ex) {
+              .trustManager(TlsTesting.loadCert("ca.pem"))
-        throw new RuntimeException(ex);
+              .build();
+        } catch (Exception ex) {
+          throw new RuntimeException(ex);
+        }
+      } else {
+        channelCredentials = TlsChannelCredentials.create();
       }
+    } else {
+      channelCredentials = InsecureChannelCredentials.create();
     }
-    return NettyChannelBuilder.forAddress(address)
+    ManagedChannelBuilder<?> builder = Grpc.newChannelBuilderForAddress(
-        .negotiationType(useTls ? NegotiationType.TLS : NegotiationType.PLAINTEXT)
+        address.getHostString(), address.getPort(), channelCredentials);
-        .sslContext(sslContext)
+    if (serverHostOverride != null) {
-        .build();
+      builder.overrideAuthority(serverHostOverride);
+    }
+    return builder.build();
   }
 
   private static String serverAddressesToString(List<InetSocketAddress> addresses) {

interop-testing/src/test/java/io/grpc/testing/integration/StressTestClientTest.java

@@ -32,8 +32,6 @@ import java.net.InetSocketAddress;
 import java.util.Arrays;
 import java.util.List;
 import java.util.Set;
-import java.util.concurrent.TimeUnit;
-import java.util.concurrent.locks.LockSupport;
 import org.junit.Rule;
 import org.junit.Test;
 import org.junit.rules.Timeout;
@@ -103,27 +101,19 @@ public class StressTestClientTest {
     assertEquals(9090, client.metricsPort());
   }
 
-  @Test
-  public void serverHostOverrideShouldBeApplied() {
-    StressTestClient client = new StressTestClient();
-    client.parseArgs(new String[] {
-        "--server_addresses=localhost:8080",
-        "--server_host_override=foo.test.google.fr",
-    });
-
-    assertEquals("foo.test.google.fr", client.addresses().get(0).getHostName());
-  }
-
   @Test
   public void gaugesShouldBeExported() throws Exception {
 
     TestServiceServer server = new TestServiceServer();
-    server.parseArgs(new String[]{"--port=" + 0, "--use_tls=false"});
+    server.parseArgs(new String[]{"--port=" + 0, "--use_tls=true"});
     server.start();
 
     StressTestClient client = new StressTestClient();
     client.parseArgs(new String[] {"--test_cases=empty_unary:1",
         "--server_addresses=localhost:" + server.getPort(), "--metrics_port=" + 0,
+        "--server_host_override=foo.test.google.fr",
+        "--use_tls=true",
+        "--use_test_ca=true",
         "--num_stubs_per_channel=2"});
     client.startMetricsService();
     client.runStressTest();
@@ -142,7 +132,7 @@ public class StressTestClientTest {
     List<GaugeResponse> allGauges =
         ImmutableList.copyOf(stub.getAllGauges(EmptyMessage.getDefaultInstance()));
     while (allGauges.size() < gaugeNames.size()) {
-      LockSupport.parkNanos(TimeUnit.MILLISECONDS.toNanos(100));
+      Thread.sleep(100);
       allGauges = ImmutableList.copyOf(stub.getAllGauges(EmptyMessage.getDefaultInstance()));
     }