[java] A draft of a Netty-based HTTP client

The default is still OkHttp. Pass -Dwebdriver.http.factory=netty to use the new one. Its stability is below my expectations yet. Everything works well if I run tests from IDEA in a single process, but there are random TimeoutException-s during a Bazel run.

java/client/client.iml

@@ -33,6 +33,9 @@
     <orderEntry type="library" scope="TEST" name="littleproxy" level="project" />
     <orderEntry type="library" name="mockito-core" level="project" />
     <orderEntry type="library" name="netty" level="project" />
+    <orderEntry type="library" name="async-http-client" level="project" />
+    <orderEntry type="library" name="netty-reactive-streams" level="project" />
+    <orderEntry type="library" name="reactive-streams" level="project" />
     <orderEntry type="library" name="objenesis" level="project" />
     <orderEntry type="library" name="okhttp" level="project" />
     <orderEntry type="library" name="opentracing" level="project" />

java/client/src/org/openqa/selenium/remote/BUILD.bazel

@@ -80,6 +80,7 @@ java_export(
         "//java/client/src/org/openqa/selenium/io",
         "//java/client/src/org/openqa/selenium/os",
         "//java/client/src/org/openqa/selenium/remote/http/okhttp",
+        "//java/client/src/org/openqa/selenium/remote/http/netty",
         "//third_party/java/bytebuddy:byte-buddy",
         "//third_party/java/guava",
     ],

java/client/src/org/openqa/selenium/remote/http/HttpClient.java

@@ -38,6 +38,16 @@ interface Factory {
     static Factory createDefault() {
       String defaultFactory = System.getProperty("webdriver.http.factory", "okhttp");
       switch (defaultFactory) {
+        case "netty":
+          try {
+            Class<? extends Factory> clazz =
+                Class.forName("org.openqa.selenium.remote.http.netty.NettyClient$Factory")
+                    .asSubclass(Factory.class);
+            return clazz.getConstructor().newInstance();
+          } catch (ReflectiveOperationException e) {
+            throw new UnsupportedOperationException("Unable to create HTTP client factory", e);
+          }
+
         case "okhttp":
         default:
           try {

java/client/src/org/openqa/selenium/remote/http/netty/BUILD.bazel

@@ -0,0 +1,15 @@
+java_library(
+    name = "netty",
+    srcs = glob(["*.java"]),
+    visibility = [
+        "//java/client/src/org/openqa/selenium/remote:__pkg__",
+        "//java/client/test/org/openqa/selenium/remote/http/netty:__pkg__",
+    ],
+    deps = [
+        "//java/client/src/org/openqa/selenium/remote/http",
+        "//third_party/java/guava",
+        "//third_party/java/netty:netty-all",
+        "//third_party/java/async-http-client",
+        "//third_party/java/reactive-streams",
+    ],
+)

java/client/src/org/openqa/selenium/remote/http/netty/CreateNettyClient.java

@@ -0,0 +1,36 @@
+// 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.remote.http.netty;
+
+import static org.asynchttpclient.Dsl.asyncHttpClient;
+
+import org.asynchttpclient.AsyncHttpClient;
+import org.openqa.selenium.remote.http.ClientConfig;
+
+import java.util.Objects;
+import java.util.function.Function;
+
+class CreateNettyClient implements Function<ClientConfig, AsyncHttpClient> {
+
+  @Override
+  public AsyncHttpClient apply(ClientConfig config) {
+    Objects.requireNonNull(config, "Client config to use must be set.");
+
+    return asyncHttpClient();
+  }
+}

java/client/src/org/openqa/selenium/remote/http/netty/NettyClient.java

@@ -0,0 +1,72 @@
+// 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.remote.http.netty;
+
+import org.openqa.selenium.remote.http.ClientConfig;
+import org.openqa.selenium.remote.http.Filter;
+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.WebSocket;
+
+import java.io.UncheckedIOException;
+import java.util.Objects;
+import java.util.function.BiFunction;
+
+public class NettyClient implements HttpClient {
+
+  private final HttpHandler handler;
+  private BiFunction<HttpRequest, WebSocket.Listener, WebSocket> toWebSocket;
+
+  private NettyClient(HttpHandler handler, BiFunction<HttpRequest, WebSocket.Listener, WebSocket> toWebSocket) {
+    this.handler = Objects.requireNonNull(handler);
+    this.toWebSocket = Objects.requireNonNull(toWebSocket);
+  }
+
+  @Override
+  public HttpResponse execute(HttpRequest request) throws UncheckedIOException {
+    return handler.execute(request);
+  }
+
+  @Override
+  public WebSocket openSocket(HttpRequest request, WebSocket.Listener listener) {
+    Objects.requireNonNull(request, "Request to send must be set.");
+    Objects.requireNonNull(listener, "WebSocket listener must be set.");
+
+    return toWebSocket.apply(request, listener);
+  }
+
+  @Override
+  public HttpClient with(Filter filter) {
+    Objects.requireNonNull(filter, "Filter to use must be set.");
+
+    // TODO: We should probably ensure that websocket requests are run through the filter.
+    return new NettyClient(handler.with(filter), toWebSocket);
+  }
+
+  public static class Factory implements HttpClient.Factory {
+
+    @Override
+    public HttpClient createClient(ClientConfig config) {
+      Objects.requireNonNull(config, "Client config to use must be set.");
+
+      return new NettyClient(new NettyHttpHandler(config).with(config.filter()), NettyWebSocket.create(config));
+    }
+  }
+}

java/client/src/org/openqa/selenium/remote/http/netty/NettyHttpHandler.java

@@ -0,0 +1,61 @@
+// 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.remote.http.netty;
+
+import org.asynchttpclient.AsyncHttpClient;
+import org.asynchttpclient.Response;
+import org.openqa.selenium.remote.http.ClientConfig;
+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.RemoteCall;
+
+import java.util.Objects;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.Future;
+
+public class NettyHttpHandler extends RemoteCall {
+
+  private final AsyncHttpClient client;
+  private final HttpHandler handler;
+
+  public NettyHttpHandler(ClientConfig config) {
+    super(config);
+    this.client = new CreateNettyClient().apply(config);
+    this.handler = config.filter().andFinally(this::makeCall);
+  }
+
+  @Override
+  public HttpResponse execute(HttpRequest request) {
+    return handler.execute(request);
+  }
+
+  private HttpResponse makeCall(HttpRequest request) {
+    Objects.requireNonNull(request, "Request must be set.");
+
+    Future<Response> whenResponse = client.executeRequest(
+        NettyMessages.toNettyRequest(getConfig().baseUri(), request));
+
+    try {
+      Response response = whenResponse.get();
+      return NettyMessages.toSeleniumResponse(response);
+    } catch (InterruptedException | ExecutionException e) {
+      throw new RuntimeException(e);
+    }
+  }
+}

java/client/src/org/openqa/selenium/remote/http/netty/NettyMessages.java

@@ -0,0 +1,88 @@
+// 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.remote.http.netty;
+
+import static org.openqa.selenium.remote.http.Contents.empty;
+
+import org.asynchttpclient.Request;
+import org.asynchttpclient.RequestBuilder;
+import org.asynchttpclient.Response;
+import org.openqa.selenium.remote.http.Contents;
+import org.openqa.selenium.remote.http.HttpMethod;
+import org.openqa.selenium.remote.http.HttpRequest;
+import org.openqa.selenium.remote.http.HttpResponse;
+
+import java.net.URI;
+
+import static org.asynchttpclient.Dsl.request;
+
+class NettyMessages {
+
+  private NettyMessages() {
+    // Utility classes.
+  }
+
+  protected static Request toNettyRequest(URI baseUrl, HttpRequest request) {
+    String rawUrl;
+
+    if (request.getUri().startsWith("ws://")) {
+      rawUrl = "http://" + request.getUri().substring("ws://".length());
+    } else if (request.getUri().startsWith("wss://")) {
+      rawUrl = "https://" + request.getUri().substring("wss://".length());
+    } else if (request.getUri().startsWith("http://") || request.getUri().startsWith("https://")) {
+      rawUrl = request.getUri();
+    } else {
+      rawUrl = baseUrl.toString().replaceAll("/$", "") + request.getUri();
+    }
+
+    RequestBuilder builder = request(request.getMethod().toString(), rawUrl);
+
+    for (String name : request.getQueryParameterNames()) {
+      for (String value : request.getQueryParameters(name)) {
+        builder.addQueryParam(name, value);
+      }
+    }
+
+    for (String name : request.getHeaderNames()) {
+      for (String value : request.getHeaders(name)) {
+        builder.addHeader(name, value);
+      }
+    }
+
+    if (request.getMethod().equals(HttpMethod.POST)) {
+      builder.setBody(request.getContent().get());
+    }
+
+    return builder.build();
+  }
+
+  public static HttpResponse toSeleniumResponse(Response response) {
+    HttpResponse toReturn = new HttpResponse();
+
+    toReturn.setStatus(response.getStatusCode());
+
+    toReturn.setContent(! response.hasResponseBody()
+                        ? empty()
+                        : Contents.memoize(response::getResponseBodyAsStream));
+
+    response.getHeaders().names().forEach(
+        name -> response.getHeaders(name).forEach(value -> toReturn.addHeader(name, value)));
+
+    return toReturn;
+  }
+}