code: // Licensed to the Software Freedom Conservancy (SFC) under one
  // or more contributor license agreements.  See the NOTICE file
  // distributed with this work for additional information
  // regarding copyright ownership.  The SFC 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.openqa.selenium.grid.router;
  
  import static java.util.concurrent.TimeUnit.SECONDS;
  import static org.assertj.core.api.Assertions.assertThat;
  import static org.openqa.selenium.remote.http.HttpMethod.GET;
  
  import com.google.common.collect.ImmutableMap;
  import com.google.common.collect.ImmutableSet;
  import java.net.URISyntaxException;
  import java.time.Instant;
  import java.util.Collections;
  import java.util.Optional;
  import java.util.UUID;
  import java.util.concurrent.CountDownLatch;
  import java.util.concurrent.atomic.AtomicReference;
  import java.util.function.Supplier;
  import java.util.stream.Stream;
  import org.junit.jupiter.api.AfterEach;
  import org.junit.jupiter.api.BeforeEach;
  import org.junit.jupiter.params.ParameterizedTest;
  import org.junit.jupiter.params.provider.Arguments;
  import org.junit.jupiter.params.provider.MethodSource;
  import org.openqa.selenium.ImmutableCapabilities;
  import org.openqa.selenium.events.EventBus;
  import org.openqa.selenium.events.local.GuavaEventBus;
  import org.openqa.selenium.grid.config.Config;
  import org.openqa.selenium.grid.config.MapConfig;
  import org.openqa.selenium.grid.data.Session;
  import org.openqa.selenium.grid.server.BaseServerOptions;
  import org.openqa.selenium.grid.server.Server;
  import org.openqa.selenium.grid.sessionmap.SessionMap;
  import org.openqa.selenium.grid.sessionmap.local.LocalSessionMap;
  import org.openqa.selenium.netty.server.NettyServer;
  import org.openqa.selenium.remote.SessionId;
  import org.openqa.selenium.remote.http.HttpClient;
  import org.openqa.selenium.remote.http.HttpHandler;
  import org.openqa.selenium.remote.http.HttpRequest;
  import org.openqa.selenium.remote.http.HttpResponse;
  import org.openqa.selenium.remote.http.TextMessage;
  import org.openqa.selenium.remote.http.WebSocket;
  import org.openqa.selenium.remote.tracing.DefaultTestTracer;
  import org.openqa.selenium.remote.tracing.Tracer;
  
  class ProxyWebsocketTest {
  
    private final HttpHandler nullHandler = req -> new HttpResponse();
    private final Config emptyConfig = new MapConfig(Collections.emptyMap());
    private Server<?> proxyServer;
    private SessionMap sessions;
  
    private String protocol;
  
    public static Stream<Arguments> data() {
      Supplier<String> s1 = () -> "cdp";
      Supplier<String> s2 = () -> "bidi";
  
      return ImmutableSet.of(s1, s2).stream().map(Arguments::of);
    }
  
    public void setFields(Supplier<String> values) {
      this.protocol = values.get();
    }
  
    @BeforeEach
    public void setUp() {
      Tracer tracer = DefaultTestTracer.createTracer();
      EventBus events = new GuavaEventBus();
  
      sessions = new LocalSessionMap(tracer, events);
  
      // Set up the proxy we'll be using
      HttpClient.Factory clientFactory = HttpClient.Factory.createDefault();
  
      ProxyWebsocketsIntoGrid proxy = new ProxyWebsocketsIntoGrid(clientFactory, sessions);
      proxyServer = new NettyServer(new BaseServerOptions(emptyConfig), nullHandler, proxy).start();
    }
  
    @AfterEach
    public void tearDown() {
      proxyServer.stop();
    }
  
    @ParameterizedTest
    @MethodSource("data")
    void shouldForwardTextMessageToServer(Supplier<String> values)
        throws URISyntaxException, InterruptedException {
      setFields(values);
  
      HttpClient.Factory clientFactory = HttpClient.Factory.createDefault();
  
      // Create a backend server which will capture any incoming text message
      AtomicReference<String> text = new AtomicReference<>();
      CountDownLatch latch = new CountDownLatch(1);
      Server<?> backend = createBackendServer(latch, text, "", emptyConfig);
  
      // Push a session that resolves to the backend server into the session map
      SessionId id = new SessionId(UUID.randomUUID());
      sessions.add(
          new Session(
              id,
              backend.getUrl().toURI(),
              new ImmutableCapabilities(),
              new ImmutableCapabilities(),
              Instant.now()));
  
      // Now! Send a message. We expect it to eventually show up in the backend
      try (WebSocket socket =
          clientFactory
              .createClient(proxyServer.getUrl())
              .openSocket(
                  new HttpRequest(GET, String.format("/session/%s/" + protocol, id)),
                  new WebSocket.Listener() {})) {
  
        socket.sendText("Cheese!");
  
        assertThat(latch.await(5, SECONDS)).isTrue();
        assertThat(text.get()).isEqualTo("Cheese!");
      }
    }
  
    @ParameterizedTest
    @MethodSource("data")
    void shouldForwardTextMessageFromServerToLocalEnd(Supplier<String> values)
        throws URISyntaxException, InterruptedException {
      setFields(values);
      HttpClient.Factory clientFactory = HttpClient.Factory.createDefault();
  
      Server<?> backend =
          createBackendServer(new CountDownLatch(1), new AtomicReference<>(), "Asiago", emptyConfig);
  
      // Push a session that resolves to the backend server into the session map
      SessionId id = new SessionId(UUID.randomUUID());
      sessions.add(
          new Session(
              id,
              backend.getUrl().toURI(),
              new ImmutableCapabilities(),
              new ImmutableCapabilities(),
              Instant.now()));
  
      // Now! Send a message. We expect it to eventually show up in the backend
      CountDownLatch latch = new CountDownLatch(1);
      AtomicReference<String> text = new AtomicReference<>();
      try (WebSocket socket =
          clientFactory
              .createClient(proxyServer.getUrl())
              .openSocket(
                  new HttpRequest(GET, String.format("/session/%s/" + protocol, id)),
                  new WebSocket.Listener() {
                    @Override
                    public void onText(CharSequence data) {
                      text.set(data.toString());
                      latch.countDown();
                    }
                  })) {
  
        socket.sendText("Cheese!");
  
        assertThat(latch.await(5, SECONDS)).isTrue();
        assertThat(text.get()).isEqualTo("Asiago");
      }
    }
  
    @ParameterizedTest
    @MethodSource("data")
    void shouldBeAbleToSendMessagesOverSecureWebSocket(Supplier<String> values)
        throws URISyntaxException, InterruptedException {
      setFields(values);
      Config secureConfig =
          new MapConfig(ImmutableMap.of("server", ImmutableMap.of("https-self-signed", true)));
  
      HttpClient.Factory clientFactory = HttpClient.Factory.createDefault();
      ProxyWebsocketsIntoGrid proxy = new ProxyWebsocketsIntoGrid(clientFactory, sessions);
  
      Server<?> backend =
          createBackendServer(new CountDownLatch(1), new AtomicReference<>(), "Cheddar", emptyConfig);
  
      Server<?> secureProxyServer =
          new NettyServer(new BaseServerOptions(secureConfig), nullHandler, proxy);
  
      secureProxyServer.start();
      // Push a session that resolves to the backend server into the session map
      SessionId id = new SessionId(UUID.randomUUID());
  
      sessions.add(
          new Session(
              id,
              backend.getUrl().toURI(),
              new ImmutableCapabilities(),
              new ImmutableCapabilities(),
              Instant.now()));
  
      CountDownLatch latch = new CountDownLatch(1);
      AtomicReference<String> text = new AtomicReference<>();
      try (WebSocket socket =
          clientFactory
              .createClient(secureProxyServer.getUrl())
              .openSocket(
                  new HttpRequest(GET, String.format("/session/%s/" + protocol, id)),
                  new WebSocket.Listener() {
                    @Override
                    public void onText(CharSequence data) {
                      text.set(data.toString());
                      latch.countDown();
                    }
                  })) {
        socket.sendText("Cheese!");
  
        assertThat(latch.await(5, SECONDS)).isTrue();
        assertThat(text.get()).isEqualTo("Cheddar");
      }
  
      secureProxyServer.stop();
    }
  
    private Server<?> createBackendServer(
        CountDownLatch latch, AtomicReference<String> incomingRef, String response, Config config) {
      return new NettyServer(
              new BaseServerOptions(config),
              nullHandler,
              (uri, sink) ->
                  Optional.of(
                      msg -> {
                        if (msg instanceof TextMessage) {
                          incomingRef.set(((TextMessage) msg).text());
                          sink.accept(new TextMessage(response));
                          latch.countDown();
                        }
                      }))
          .start();
    }
  }
  