hadoop ProfileOutputServlet 源码

haddop ProfileOutputServlet 代码

文件路径：/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/http/ProfileOutputServlet.java

/*
 * 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.hadoop.http;

import java.io.File;
import java.io.IOException;
import java.util.regex.Pattern;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.eclipse.jetty.servlet.DefaultServlet;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import org.apache.hadoop.classification.InterfaceAudience;

/**
 * Servlet to serve files generated by {@link ProfileServlet}.
 */
@InterfaceAudience.Private
public class ProfileOutputServlet extends DefaultServlet {

  private static final long serialVersionUID = 1L;

  private static final Logger LOG = LoggerFactory.getLogger(ProfileOutputServlet.class);
  // default refresh period 2 sec
  private static final int REFRESH_PERIOD = 2;
  // Alphanumeric characters, plus percent (url-encoding), equals, ampersand, dot and hyphen
  private static final Pattern ALPHA_NUMERIC = Pattern.compile("[a-zA-Z0-9%=&.\\-]*");

  @Override
  protected void doGet(final HttpServletRequest req, final HttpServletResponse resp)
      throws ServletException, IOException {
    if (!HttpServer2.isInstrumentationAccessAllowed(getServletContext(), req, resp)) {
      resp.setStatus(HttpServletResponse.SC_UNAUTHORIZED);
      ProfileServlet.setResponseHeader(resp);
      resp.getWriter().write("Unauthorized: Instrumentation access is not allowed!");
      return;
    }

    String absoluteDiskPath = getServletContext().getRealPath(req.getPathInfo());
    File requestedFile = new File(absoluteDiskPath);
    // async-profiler version 1.4 writes 'Started [cpu] profiling' to output file when profiler is
    // running which gets replaced by final output. If final output is not ready yet, the file size
    // will be <100 bytes (in all modes).
    if (requestedFile.length() < 100) {
      LOG.info("{} is incomplete. Sending auto-refresh header.", requestedFile);
      String refreshUrl = req.getRequestURI();
      // Rebuild the query string (if we have one)
      if (req.getQueryString() != null) {
        refreshUrl += "?" + sanitize(req.getQueryString());
      }
      ProfileServlet.setResponseHeader(resp);
      resp.setHeader("Refresh", REFRESH_PERIOD + ";" + refreshUrl);
      resp.getWriter().write("This page will be auto-refreshed every " + REFRESH_PERIOD
          + " seconds until the output file is ready. Redirecting to " + refreshUrl);
    } else {
      super.doGet(req, resp);
    }
  }

  static String sanitize(String input) {
    // Basic test to try to avoid any XSS attacks or HTML content showing up.
    // Duplicates HtmlQuoting a little, but avoid destroying ampersand.
    if (ALPHA_NUMERIC.matcher(input).matches()) {
      return input;
    }
    throw new RuntimeException("Non-alphanumeric data found in input, aborting.");
  }
}

相关信息

hadoop 源码目录

相关文章

hadoop AdminAuthorizedServlet 源码

hadoop FilterContainer 源码

hadoop FilterInitializer 源码

hadoop HtmlQuoting 源码

hadoop HttpConfig 源码

hadoop HttpRequestLog 源码

hadoop HttpServer2 源码

hadoop HttpServer2Metrics 源码

hadoop IsActiveServlet 源码

hadoop JettyUtils 源码