Provide a pure JRE implementation of HttpClient

So we can avoid having to take a dependency on Apache
HttpClient.

Author: shs96c

java/client/src/org/openqa/selenium/remote/internal/JreHttpClient.java

@@ -0,0 +1,114 @@
+// 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.internal;
+
+import org.openqa.selenium.remote.http.HttpClient;
+import org.openqa.selenium.remote.http.HttpMethod;
+import org.openqa.selenium.remote.http.HttpRequest;
+import org.openqa.selenium.remote.http.HttpResponse;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.net.HttpURLConnection;
+import java.net.URL;
+import java.util.List;
+import java.util.Map;
+import java.util.Objects;
+
+public class JreHttpClient implements HttpClient {
+
+  private final URL url;
+
+  private JreHttpClient(URL url) {
+    if (!url.getProtocol().toLowerCase().startsWith("http")) {
+      throw new IllegalArgumentException("Base URL must be an http URL: " + url);
+    }
+    this.url = url;
+  }
+
+  @Override
+  public HttpResponse execute(HttpRequest request, boolean followRedirects) throws IOException {
+    URL url = new URL(this.url.toString() + request.getUri());
+
+    HttpURLConnection connection = (HttpURLConnection) url.openConnection();
+    try {
+      connection.setInstanceFollowRedirects(followRedirects);
+      for (String name : request.getHeaderNames()) {
+        for (String value : request.getHeaders(name)) {
+          connection.addRequestProperty(name, value);
+        }
+      }
+      connection.setRequestProperty("Content-length", String.valueOf(request.getContent().length));
+      connection.setRequestMethod(request.getMethod().toString());
+      connection.setDoInput(true);
+
+      if (request.getMethod() == HttpMethod.POST) {
+        connection.setDoOutput(true);
+        try (OutputStream os = connection.getOutputStream()) {
+          os.write(request.getContent());
+        }
+      }
+
+      HttpResponse response = new HttpResponse();
+      response.setStatus(connection.getResponseCode());
+
+      for (Map.Entry<String, List<String>> entry : connection.getHeaderFields().entrySet()) {
+        // HttpURLConnection stores headers in a HashMap. The order they come back is basically
+        // random.
+        for (String value : entry.getValue()) {
+          response.addHeader(entry.getKey(), value);
+        }
+      }
+
+      InputStream is = connection.getErrorStream();
+      if (is == null) {
+        is = connection.getInputStream();
+      }
+      try (ByteArrayOutputStream bos = new ByteArrayOutputStream()) {
+        int count;
+        byte[] data = new byte[1024];
+        while ((count = is.read(data, 0, data.length)) != -1) {
+          bos.write(data, 0, count);
+        }
+        bos.flush();
+        response.setContent(bos.toByteArray());
+      } finally {
+        is.close();
+      }
+
+      return response;
+    } finally {
+      connection.disconnect();
+    }
+  }
+
+  @Override
+  public void close() throws IOException {
+
+  }
+
+  public static class Factory implements HttpClient.Factory {
+
+    @Override
+    public HttpClient createClient(URL url) {
+      return new JreHttpClient(Objects.requireNonNull(url, "Base URL must be set"));
+    }
+  }
+}

java/client/test/org/openqa/selenium/remote/internal/JreHttpClientTest.java

@@ -0,0 +1,105 @@
+// 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.internal;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+
+import com.google.common.collect.HashMultimap;
+import com.google.common.collect.ImmutableList;
+import com.google.common.collect.Multimap;
+
+import org.junit.Test;
+import org.openqa.selenium.net.PortProber;
+import org.openqa.selenium.remote.http.HttpClient;
+import org.openqa.selenium.remote.http.HttpMethod;
+import org.openqa.selenium.remote.http.HttpRequest;
+import org.openqa.selenium.remote.http.HttpResponse;
+import org.seleniumhq.jetty9.server.Server;
+import org.seleniumhq.jetty9.servlet.ServletContextHandler;
+import org.seleniumhq.jetty9.servlet.ServletHolder;
+
+import java.io.IOException;
+
+import javax.servlet.ServletException;
+import javax.servlet.http.HttpServlet;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
+
+public class JreHttpClientTest {
+
+  @Test
+  public void responseShouldCaptureASingleHeader() throws Exception {
+    HashMultimap<String, String> headers = HashMultimap.create();
+    headers.put("Cake", "Delicious");
+
+    HttpResponse response = getResponseWithHeaders(headers);
+
+    String value = response.getHeader("Cake");
+    assertEquals("Delicious", value);
+  }
+
+  /**
+   * The HTTP Spec that it should be
+   * <a href="https://www.w3.org/Protocols/rfc2616/rfc2616-sec4.html#sec4.2">safe to combine them
+   * </a>, but things like the <a href="https://www.ietf.org/rfc/rfc2109.txt">cookie spec</a> make
+   * this hard (notably when a legal value may contain a comma).
+   */
+  @Test
+  public void responseShouldKeepMultipleHeadersSeparate() throws Exception {
+    HashMultimap<String, String> headers = HashMultimap.create();
+    headers.put("Cheese", "Cheddar");
+    headers.put("Cheese", "Brie, Gouda");
+
+    HttpResponse response = getResponseWithHeaders(headers);
+
+    ImmutableList<String> values = ImmutableList.copyOf(response.getHeaders("Cheese"));
+
+    assertTrue(values.contains("Cheddar"));
+    assertTrue(values.contains("Brie, Gouda"));
+  }
+
+  private HttpResponse getResponseWithHeaders(final Multimap<String, String> headers)
+      throws Exception {
+    Server server = new Server(PortProber.findFreePort());
+    ServletContextHandler handler = new ServletContextHandler();
+    handler.setContextPath("");
+
+    class Headers extends HttpServlet {
+      @Override
+      protected void doGet(HttpServletRequest req, HttpServletResponse resp)
+          throws ServletException, IOException {
+        headers.forEach(resp::addHeader);
+        resp.setContentLengthLong(0);
+      }
+    }
+    ServletHolder holder = new ServletHolder(new Headers());
+    handler.addServlet(holder, "/*");
+
+    server.setHandler(handler);
+
+    server.start();
+    try {
+      HttpClient client = new JreHttpClient.Factory().createClient(server.getURI().toURL());
+      HttpRequest request = new HttpRequest(HttpMethod.GET, "/foo");
+      return client.execute(request, true);
+    } finally {
+      server.stop();
+    }
+  }
+}