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.beam.runners.dataflow.worker.status;
  
  import java.io.IOException;
  import java.io.OutputStreamWriter;
  import java.io.PrintWriter;
  import java.nio.charset.StandardCharsets;
  import java.util.Map;
  import java.util.concurrent.TimeUnit;
  import javax.servlet.ServletException;
  import javax.servlet.ServletOutputStream;
  import javax.servlet.http.HttpServletRequest;
  import javax.servlet.http.HttpServletResponse;
  import org.apache.beam.runners.dataflow.worker.status.DebugCapture.Capturable;
  import org.apache.beam.runners.fnexecution.status.BeamWorkerStatusGrpcService;
  import org.apache.beam.vendor.guava.v32_1_2_jre.com.google.common.base.Strings;
  
  /**
   * Servlet dedicated to provide live status info retrieved from SDK Harness. Note this is different
   * from {@link WorkerStatusPages} which incorporates all info for Dataflow runner including this
   * SDKWorkerStatus page.
   */
  public class SdkWorkerStatusServlet extends BaseStatusServlet implements Capturable {
  
    private final transient BeamWorkerStatusGrpcService statusGrpcService;
  
    public SdkWorkerStatusServlet(BeamWorkerStatusGrpcService statusGrpcService) {
      super("sdk_status");
      this.statusGrpcService = statusGrpcService;
    }
  
    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response)
        throws IOException, ServletException {
      String id = request.getParameter("id");
      if (Strings.isNullOrEmpty(id)) {
        // return all connected sdk statuses if no id provided.
        response.setContentType("text/html;charset=utf-8");
        ServletOutputStream writer = response.getOutputStream();
        try (PrintWriter out =
            new PrintWriter(new OutputStreamWriter(writer, StandardCharsets.UTF_8))) {
          captureData(out);
        }
      } else {
        response.setContentType("text/plain;charset=utf-8");
        ServletOutputStream writer = response.getOutputStream();
        writer.println(statusGrpcService.getSingleWorkerStatus(id, 10, TimeUnit.SECONDS));
      }
      response.setStatus(HttpServletResponse.SC_OK);
      response.flushBuffer();
    }
  
    @Override
    public String pageName() {
      return "/sdk_status";
    }
  
    @Override
    public void captureData(PrintWriter writer) {
      Map<String, String> allStatuses = statusGrpcService.getAllWorkerStatuses(10, TimeUnit.SECONDS);
  
      writer.println("<html>");
      writer.println("<h1>SDK harness</h1>");
      // add links to each sdk section for easier navigation.
      for (String sdkId : allStatuses.keySet()) {
        writer.print(String.format("<a href=\"#%s\">%s</a> ", sdkId, sdkId));
      }
      writer.println();
  
      for (Map.Entry<String, String> entry : allStatuses.entrySet()) {
        writer.println(String.format("<h2 id=\"%s\">%s</h2>", entry.getKey(), entry.getKey()));
        writer.println("<a href=\"#top\">return to top</a>");
        writer.println("<div style=\"white-space:pre-wrap\">");
        writer.println(entry.getValue());
        writer.println("</div>");
        writer.println("");
      }
      writer.println("</html>");
    }
  }
  