sentry-service/sentry-service-web/src/main/java/org/apache/sentry/service/web/PubSubServlet.java - sentry - Git at Google

 /*
  * 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.sentry.service.web;

 import org.apache.sentry.core.common.utils.PubSub;

 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;

 import javax.servlet.ServletException;
 import javax.servlet.ServletRequest;
 import javax.servlet.http.HttpServlet;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 import java.io.IOException;
 import java.io.PrintWriter;

 import static org.apache.commons.lang.StringEscapeUtils.escapeHtml;

 /**
  * This servlet facilitates sending {topic, message } tuples to Servlet components
  * subscribed to specific topics.
  * <p>
  * It uses publish-subscribe mechanism implemented by PubSub class.
  * The form generated by this servlet consists of the following elements:
  * <p>
  * a) Topic: pull-down menu of existing topics, i.e. the topics registered with
  * PubSub by calling PubSub.subscribe() API. This prevents entering invalid topic.
  * <p>
  * b) Message: text field for entering a message
  * <p>
  * c) Submit: button to submit (topic, message) tuple
  * <p>
  * d) Status: text area printing status of the request or help information.
  */
 public class PubSubServlet extends HttpServlet {

   private static final Logger LOGGER = LoggerFactory.getLogger(PubSubServlet.class);

   private static final String FORM_GET =
     "<!DOCTYPE html>" +
     "<html>" +
     "<body>" +
     "<form>" +
     "<br><br><b>Topic:</b><br><br>" +
     "<select name='topic'/>%s</select>" +
     "<br><br><b>Message:</b><br><br>" +
     "<input type='text' size='50' name='message'/>" +
     "<br><br>" +
     "<input type='submit' value='Submit'/>" +
     "</form>" +
     "<br><br><b>Status:</b><br><br>" +
     "<textarea rows='4' cols='50'>%s</textarea>" +
     "</body>" +
     "</html>";

   /**
    * Return parameter on servlet request for the given name
    *
    * @param request: Servlet request
    * @param name: Name of parameter in servlet request
    * @return Parameter in servlet request for the given name, return null if can't find parameter.
    */
   private static String getParameter(ServletRequest request, String name) {
     String s = request.getParameter(name);
     if (s == null) {
       return null;
     }
     s = s.trim();
     return s.isEmpty() ? null : s;
   }

   /**
    * Parse the topic and message values and submit them via PubSub.submit() API.
    * Reject request for unknown topic, i.e. topic no one is subscribed to.
    */
   @Override
   public void doGet(HttpServletRequest request, HttpServletResponse response)
           throws ServletException, IOException {
     String topic = getParameter(request, "topic");
     String message = getParameter(request, "message");
     response.setContentType("text/html;charset=utf-8");
     response.setStatus(HttpServletResponse.SC_OK);
     PrintWriter out = response.getWriter();

     String msg = "Topic is required, Message is optional.\nValid topics: " + PubSub.getInstance().getTopics();
     if (topic != null) {
       LOGGER.info("Submitting topic " + topic + ", message " + message);
       try {
         PubSub.getInstance().publish(PubSub.Topic.fromString(topic), message);
         msg = "Submitted topic " + topic + ", message " + message;
       } catch (Exception e) {
         msg = "Failed to submit topic " + topic + ", message " + message + " - " + e.getMessage();
         LOGGER.error(msg);
         response.sendError(HttpServletResponse.SC_BAD_REQUEST, msg);
         return;
       }
     }

     StringBuilder topics = new StringBuilder();
     for (PubSub.Topic t : PubSub.getInstance().getTopics()) {
       topics.append("<option>").append(t.getName()).append("</option>");
     }

     String output = String.format(FORM_GET, topics.toString(), escapeHtml(msg));
     if (LOGGER.isDebugEnabled()) {
       LOGGER.debug("HTML Page: " + output);
     }
     out.write(output);
     out.close();
     response.flushBuffer();
   }
 }
	/*
	* 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.sentry.service.web;

	import org.apache.sentry.core.common.utils.PubSub;

	import org.slf4j.Logger;
	import org.slf4j.LoggerFactory;

	import javax.servlet.ServletException;
	import javax.servlet.ServletRequest;
	import javax.servlet.http.HttpServlet;
	import javax.servlet.http.HttpServletRequest;
	import javax.servlet.http.HttpServletResponse;
	import java.io.IOException;
	import java.io.PrintWriter;

	import static org.apache.commons.lang.StringEscapeUtils.escapeHtml;

	/**
	* This servlet facilitates sending {topic, message } tuples to Servlet components
	* subscribed to specific topics.
	* <p>
	* It uses publish-subscribe mechanism implemented by PubSub class.
	* The form generated by this servlet consists of the following elements:
	* <p>
	* a) Topic: pull-down menu of existing topics, i.e. the topics registered with
	* PubSub by calling PubSub.subscribe() API. This prevents entering invalid topic.
	* <p>
	* b) Message: text field for entering a message
	* <p>
	* c) Submit: button to submit (topic, message) tuple
	* <p>
	* d) Status: text area printing status of the request or help information.
	*/
	public class PubSubServlet extends HttpServlet {

	private static final Logger LOGGER = LoggerFactory.getLogger(PubSubServlet.class);

	private static final String FORM_GET =
	"<!DOCTYPE html>" +
	"<html>" +
	"<body>" +
	"<form>" +
	"<br><br><b>Topic:</b><br><br>" +
	"<select name='topic'/>%s</select>" +
	"<br><br><b>Message:</b><br><br>" +
	"<input type='text' size='50' name='message'/>" +
	"<br><br>" +
	"<input type='submit' value='Submit'/>" +
	"</form>" +
	"<br><br><b>Status:</b><br><br>" +
	"<textarea rows='4' cols='50'>%s</textarea>" +
	"</body>" +
	"</html>";

	/**
	* Return parameter on servlet request for the given name
	*
	* @param request: Servlet request
	* @param name: Name of parameter in servlet request
	* @return Parameter in servlet request for the given name, return null if can't find parameter.
	*/
	private static String getParameter(ServletRequest request, String name) {
	String s = request.getParameter(name);
	if (s == null) {
	return null;
	}
	s = s.trim();
	return s.isEmpty() ? null : s;
	}

	/**
	* Parse the topic and message values and submit them via PubSub.submit() API.
	* Reject request for unknown topic, i.e. topic no one is subscribed to.
	*/
	@Override
	public void doGet(HttpServletRequest request, HttpServletResponse response)
	throws ServletException, IOException {
	String topic = getParameter(request, "topic");
	String message = getParameter(request, "message");
	response.setContentType("text/html;charset=utf-8");
	response.setStatus(HttpServletResponse.SC_OK);
	PrintWriter out = response.getWriter();

	String msg = "Topic is required, Message is optional.\nValid topics: " + PubSub.getInstance().getTopics();
	if (topic != null) {
	LOGGER.info("Submitting topic " + topic + ", message " + message);
	try {
	PubSub.getInstance().publish(PubSub.Topic.fromString(topic), message);
	msg = "Submitted topic " + topic + ", message " + message;
	} catch (Exception e) {
	msg = "Failed to submit topic " + topic + ", message " + message + " - " + e.getMessage();
	LOGGER.error(msg);
	response.sendError(HttpServletResponse.SC_BAD_REQUEST, msg);
	return;
	}
	}

	StringBuilder topics = new StringBuilder();
	for (PubSub.Topic t : PubSub.getInstance().getTopics()) {
	topics.append("<option>").append(t.getName()).append("</option>");
	}

	String output = String.format(FORM_GET, topics.toString(), escapeHtml(msg));
	if (LOGGER.isDebugEnabled()) {
	LOGGER.debug("HTML Page: " + output);
	}
	out.write(output);
	out.close();
	response.flushBuffer();
	}
	}