content: /*
   * Licensed to the Apache Software Foundation (ASF) under one or more
   * contributor license agreements.  See the NOTICE file distributed with
   * this work for additional information regarding copyright ownership.
   * The ASF licenses this file to You under the Apache License, Version 2.0
   * (the "License"); you may not use this file except in compliance with
   * the License.  You may obtain a copy of the License at
   *
   *    http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package org.apache.arrow.flight;
  
  import static org.junit.jupiter.api.Assertions.assertEquals;
  import static org.junit.jupiter.api.Assertions.assertFalse;
  import static org.junit.jupiter.api.Assertions.assertThrows;
  import static org.junit.jupiter.api.Assertions.assertTrue;
  import static org.junit.jupiter.api.Assertions.fail;
  
  import com.google.protobuf.Empty;
  import io.grpc.BindableService;
  import io.grpc.ConnectivityState;
  import io.grpc.ManagedChannel;
  import io.grpc.Server;
  import io.grpc.inprocess.InProcessChannelBuilder;
  import io.grpc.inprocess.InProcessServerBuilder;
  import io.grpc.stub.StreamObserver;
  import java.io.IOException;
  import java.util.concurrent.ExecutorService;
  import java.util.concurrent.Executors;
  import org.apache.arrow.flight.auth.ServerAuthHandler;
  import org.apache.arrow.memory.BufferAllocator;
  import org.apache.arrow.memory.RootAllocator;
  import org.junit.jupiter.api.AfterEach;
  import org.junit.jupiter.api.BeforeEach;
  import org.junit.jupiter.api.Test;
  
  /** Unit test which adds 2 services to same server end point. */
  public class TestFlightGrpcUtils {
    private Server server;
    private BufferAllocator allocator;
    private String serverName;
  
    @BeforeEach
    public void setup() throws IOException {
      // Defines flight service
      allocator = new RootAllocator(Integer.MAX_VALUE);
      final NoOpFlightProducer producer = new NoOpFlightProducer();
      final ServerAuthHandler authHandler = ServerAuthHandler.NO_OP;
      final ExecutorService exec = Executors.newCachedThreadPool();
      final BindableService flightBindingService =
          FlightGrpcUtils.createFlightService(allocator, producer, authHandler, exec);
  
      // initializes server with 2 services - FlightBindingService & TestService
      serverName = InProcessServerBuilder.generateName();
      server =
          InProcessServerBuilder.forName(serverName)
              .directExecutor()
              .addService(flightBindingService)
              .addService(new TestServiceAdapter())
              .build();
      server.start();
    }
  
    @AfterEach
    public void cleanup() {
      server.shutdownNow();
    }
  
    /**
     * This test checks if multiple gRPC services can be added to the same server endpoint and if they
     * can be used by different clients via the same channel.
     *
     * @throws IOException If server fails to start.
     */
    @Test
    public void testMultipleGrpcServices() throws IOException {
      // Initializes channel so that multiple clients can communicate with server
      final ManagedChannel managedChannel =
          InProcessChannelBuilder.forName(serverName).directExecutor().build();
  
      // Defines flight client and calls service method. Since we use a NoOpFlightProducer we expect
      // the service
      // to throw a RunTimeException
      final FlightClient flightClient = FlightGrpcUtils.createFlightClient(allocator, managedChannel);
      final Iterable<ActionType> actionTypes = flightClient.listActions();
      assertThrows(
          FlightRuntimeException.class,
          () -> actionTypes.forEach(actionType -> System.out.println(actionType.toString())));
  
      // Define Test client as a blocking stub and call test method which correctly returns an empty
      // protobuf object
      final TestServiceGrpc.TestServiceBlockingStub blockingStub =
          TestServiceGrpc.newBlockingStub(managedChannel);
      assertEquals(Empty.newBuilder().build(), blockingStub.test(Empty.newBuilder().build()));
    }
  
    @Test
    public void testShutdown() throws IOException, InterruptedException {
      // Initializes channel so that multiple clients can communicate with server
      final ManagedChannel managedChannel =
          InProcessChannelBuilder.forName(serverName).directExecutor().build();
  
      // Defines flight client and calls service method. Since we use a NoOpFlightProducer we expect
      // the service
      // to throw a RunTimeException
      final FlightClient flightClient =
          FlightGrpcUtils.createFlightClientWithSharedChannel(allocator, managedChannel);
  
      // Should be a no-op.
      flightClient.close();
      assertFalse(managedChannel.isShutdown());
      assertFalse(managedChannel.isTerminated());
      assertEquals(ConnectivityState.IDLE, managedChannel.getState(false));
      managedChannel.shutdownNow();
    }
  
    @Test
    public void testProxyChannel() throws IOException, InterruptedException {
      // Initializes channel so that multiple clients can communicate with server
      final ManagedChannel managedChannel =
          InProcessChannelBuilder.forName(serverName).directExecutor().build();
  
      final FlightGrpcUtils.NonClosingProxyManagedChannel proxyChannel =
          new FlightGrpcUtils.NonClosingProxyManagedChannel(managedChannel);
      assertFalse(proxyChannel.isShutdown());
      assertFalse(proxyChannel.isTerminated());
      proxyChannel.shutdown();
      assertTrue(proxyChannel.isShutdown());
      assertTrue(proxyChannel.isTerminated());
      assertEquals(ConnectivityState.SHUTDOWN, proxyChannel.getState(false));
      try {
        proxyChannel.newCall(null, null);
        fail();
      } catch (IllegalStateException e) {
        // This is expected, since the proxy channel is shut down.
      }
  
      assertFalse(managedChannel.isShutdown());
      assertFalse(managedChannel.isTerminated());
      assertEquals(ConnectivityState.IDLE, managedChannel.getState(false));
  
      managedChannel.shutdownNow();
    }
  
    @Test
    public void testProxyChannelWithClosedChannel() throws IOException, InterruptedException {
      // Initializes channel so that multiple clients can communicate with server
      final ManagedChannel managedChannel =
          InProcessChannelBuilder.forName(serverName).directExecutor().build();
  
      final FlightGrpcUtils.NonClosingProxyManagedChannel proxyChannel =
          new FlightGrpcUtils.NonClosingProxyManagedChannel(managedChannel);
      assertFalse(proxyChannel.isShutdown());
      assertFalse(proxyChannel.isTerminated());
      managedChannel.shutdownNow();
      assertTrue(proxyChannel.isShutdown());
      assertTrue(proxyChannel.isTerminated());
      assertEquals(ConnectivityState.SHUTDOWN, proxyChannel.getState(false));
      try {
        proxyChannel.newCall(null, null);
        fail();
      } catch (IllegalStateException e) {
        // This is expected, since the proxy channel is shut down.
      }
  
      assertTrue(managedChannel.isShutdown());
      assertTrue(managedChannel.isTerminated());
      assertEquals(ConnectivityState.SHUTDOWN, managedChannel.getState(false));
    }
  
    /** Private class used for testing purposes that overrides service behavior. */
    private static class TestServiceAdapter extends TestServiceGrpc.TestServiceImplBase {
  
      /**
       * gRPC service that receives an empty object & returns and empty protobuf object.
       *
       * @param request google.protobuf.Empty
       * @param responseObserver google.protobuf.Empty
       */
      @Override
      public void test(Empty request, StreamObserver<Empty> responseObserver) {
        responseObserver.onNext(Empty.newBuilder().build());
        responseObserver.onCompleted();
      }
    }
  }
  