Java tutorial
/** * Copyright 2012 Comcast Corporation * * Licensed 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 com.comcast.cmb.common.controller; import java.io.BufferedReader; import java.io.DataOutputStream; import java.io.FileReader; import java.io.IOException; import java.io.InputStreamReader; import java.io.PrintWriter; import java.net.HttpURLConnection; import java.net.URI; import java.net.URL; import java.util.HashMap; import java.util.Map; import java.util.Map.Entry; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import javax.servlet.http.HttpSession; import org.apache.log4j.Logger; import org.jfree.util.Log; import com.amazonaws.Request; import com.amazonaws.auth.AWS4Signer; import com.amazonaws.auth.AWSCredentials; import com.amazonaws.auth.BasicAWSCredentials; import com.amazonaws.services.sns.AmazonSNSClient; import com.amazonaws.services.sqs.AmazonSQSClient; import com.amazonaws.services.sqs.model.CreateQueueRequest; import com.amazonaws.services.sqs.model.transform.CreateQueueRequestMarshaller; import com.comcast.cmb.common.model.User; import com.comcast.cmb.common.persistence.IUserPersistence; import com.comcast.cmb.common.persistence.PersistenceFactory; import com.comcast.cmb.common.util.CMBProperties; import com.comcast.cmb.common.util.PersistenceException; /** * Admin servlet base * @author bwolf * */ public abstract class AdminServletBase extends HttpServlet { private static final long serialVersionUID = 1L; public static final String cnsServiceBaseUrl = CMBProperties.getInstance().getCNSServiceUrl(); public static final String cqsServiceBaseUrl = CMBProperties.getInstance().getCQSServiceUrl(); protected volatile User user = null; protected volatile AmazonSQSClient sqs = null; protected volatile AmazonSNSClient sns = null; private volatile BasicAWSCredentials awsCredentials = null; private static Logger logger = Logger.getLogger(AdminServletBase.class); protected boolean isAuthenticated(HttpServletRequest request) { HttpSession session = request.getSession(true); if (session.getAttribute("USER") != null) { return true; } else { return false; } } protected User getAuthenticatedUser(HttpServletRequest request) { if (isAuthenticated(request)) { return (User) request.getSession(true).getAttribute("USER"); } else { return null; } } protected boolean isAdmin(HttpServletRequest request) { if (!isAuthenticated(request)) { return false; } User user = (User) request.getSession(true).getAttribute("USER"); return user.getIsAdmin(); } protected boolean redirectUnauthenticatedUser(HttpServletRequest request, HttpServletResponse response) throws IOException { if (!isAuthenticated(request)) { response.sendRedirect(response.encodeURL("/webui/userlogin")); return true; } return false; } protected boolean redirectNonAdminUser(HttpServletRequest request, HttpServletResponse response) throws IOException { if (!isAuthenticated(request)) { response.sendRedirect(response.encodeURL("/webui/userlogin")); return true; } if (!isAdmin(request)) { response.sendRedirect( response.encodeURL("/webui/user?userId=" + getAuthenticatedUser(request).getUserId())); return true; } return false; } protected void logout(HttpServletRequest request, HttpServletResponse response) throws IOException { HttpSession session = request.getSession(true); if (session.getAttribute("USER") != null) { logger.info("event=logout user_name=" + ((User) session.getAttribute("USER")).getUserName() + " user_id=" + ((User) session.getAttribute("USER")).getUserId()); session.removeAttribute("USER"); } response.sendRedirect(response.encodeURL("/webui/userlogin")); } /** * Method to set the aws credentials for sqs and sns handlers * @param userId * @throws ServletException */ protected void connect(HttpServletRequest request) throws ServletException { String userId = request.getParameter("userId"); IUserPersistence userHandler = PersistenceFactory.getUserPersistence(); try { user = userHandler.getUserById(userId); } catch (PersistenceException ex) { throw new ServletException(ex); } if (user == null) { throw new ServletException("User " + userId + " does not exist"); } if (!user.getUserName().equals(getAuthenticatedUser(request).getUserName()) && !getAuthenticatedUser(request).getIsAdmin()) { throw new ServletException("Only admin may impersonate other users"); } awsCredentials = new BasicAWSCredentials(user.getAccessKey(), user.getAccessSecret()); sqs = new AmazonSQSClient(awsCredentials); sqs.setEndpoint(CMBProperties.getInstance().getCQSServiceUrl()); sns = new AmazonSNSClient(awsCredentials); sns.setEndpoint(CMBProperties.getInstance().getCNSServiceUrl()); } protected void simpleHeader(HttpServletRequest request, PrintWriter out, String title) throws ServletException { out.println("<head>"); out.println("<meta content='text/html; charset=UTF-8' http-equiv='Content-Type'/>"); out.println("<title>CMB Admin - " + title + "</title>"); //out.println("<link rel='stylesheet' type='text/css' href='/global.css'/>"); out.println("<style media='screen' type='text/css'>"); try { BufferedReader br = new BufferedReader( new FileReader(getServletContext().getRealPath("WEB-INF/global.css"))); String line; StringBuffer sb = new StringBuffer(""); while ((line = br.readLine()) != null) { sb.append(line).append("\n"); } br.close(); out.println(sb.toString()); } catch (Exception ex) { Log.error("event=failed_to_read_css", ex); } out.println("</style>"); out.println("</head>"); } /** * Generate standard heading in the response. * @param out * @throws ServletException * @throws IOException */ protected void header(HttpServletRequest request, PrintWriter out, String title) throws ServletException { simpleHeader(request, out, title); if (isAuthenticated(request)) { out.println("<span class='header'>"); out.println("<table width='100%' border='0'><tr><td width='100%' align='left'>Welcome " + getAuthenticatedUser(request).getUserName() + " | "); if (isAdmin(request)) { out.println("<a href='/webui'>All Users</a>" + " | "); if (user != null) { out.println("<a href='/webui/cnsuser?userId=" + user.getUserId() + "'>" + user.getUserName() + "'s Topics</a>" + " | "); out.println("<a href='/webui/cqsuser?userId=" + user.getUserId() + "'>" + user.getUserName() + "'s Queues</a>" + " | "); } else { User mainUser = getAuthenticatedUser(request); out.println("<a href='/webui/cnsuser?userId=" + mainUser.getUserId() + "'>" + mainUser.getUserName() + "'s Topics</a>" + " | "); out.println("<a href='/webui/cqsuser?userId=" + mainUser.getUserId() + "'>" + mainUser.getUserName() + "'s Queues</a>" + " | "); } out.println("<a href='/webui/cnsworkerstate'>CNS Dashboard</a>" + " | "); out.println("<a href='/webui/cqsapistate'>CQS Dashboard</a>" + " | "); if (CMBProperties.getInstance().isCMBStatsEnabled()) { out.println("<a href='/webui/cmbcallstats'>Stats</a>" + " | "); } } else { User mainUser = getAuthenticatedUser(request); out.println("<a href='/webui/cnsuser?userId=" + mainUser.getUserId() + "'> Topics</a>" + " | "); out.println("<a href='/webui/cqsuser?userId=" + mainUser.getUserId() + "'> Queues</a>" + " | "); } out.println("<a href='/webui/userlogin?Logout=Logout'>logout</a></td></tr></table>"); out.println("</span>"); } out.println("<h1>CMB - Comcast Message Bus - V " + CMBControllerServlet.VERSION + "</h1>"); if (!CMBProperties.getInstance().getCMBDeploymentName().equals("")) { out.println("<h3>" + CMBProperties.getInstance().getCMBDeploymentName() + "</h3>"); } } protected String httpGet(String urlString) { URL url; HttpURLConnection conn; BufferedReader br; String line; String doc = ""; try { url = new URL(urlString); conn = (HttpURLConnection) url.openConnection(); conn.setRequestMethod("GET"); br = new BufferedReader(new InputStreamReader(conn.getInputStream())); while ((line = br.readLine()) != null) { doc += line; } br.close(); logger.info("event=http_get url=" + urlString); } catch (Exception ex) { logger.error("event=http_get url=" + urlString, ex); } return doc; } protected String httpPOST(String baseUrl, String urlString, AWSCredentials awsCredentials) { URL url; HttpURLConnection conn; BufferedReader br; String line; String doc = ""; try { String urlPost = urlString.substring(0, urlString.indexOf("?")); url = new URL(urlPost); conn = (HttpURLConnection) url.openConnection(); conn.setRequestMethod("POST"); CreateQueueRequest createQueueRequest = new CreateQueueRequest("test"); Request<CreateQueueRequest> request = new CreateQueueRequestMarshaller().marshall(createQueueRequest); //set parameters from url String parameterString = urlString.substring(urlString.indexOf("?") + 1); String[] parameterArray = parameterString.split("&"); Map<String, String> requestParameters = new HashMap<String, String>(); for (int i = 0; i < parameterArray.length; i++) { requestParameters.put(parameterArray[i].substring(0, parameterArray[i].indexOf("=")), parameterArray[i].substring(parameterArray[i].indexOf("=") + 1)); } request.setParameters(requestParameters); //get endpoint from url URI uri = new URI(baseUrl); request.setEndpoint(uri); String resourcePath = urlString.substring(baseUrl.length(), urlString.indexOf("?")); request.setResourcePath(resourcePath); AWS4Signer aws4Signer = new AWS4Signer(); String host = uri.getHost(); aws4Signer.setServiceName(host); aws4Signer.sign(request, awsCredentials); //set headers for real request for (Entry<String, String> entry : request.getHeaders().entrySet()) { conn.setRequestProperty(entry.getKey(), entry.getValue()); } // Send post request conn.setDoOutput(true); DataOutputStream wr = new DataOutputStream(conn.getOutputStream()); StringBuffer bodyStringBuffer = new StringBuffer(); for (Entry<String, String> entry : requestParameters.entrySet()) { bodyStringBuffer.append(entry.getKey() + "=" + entry.getValue() + "&"); } String bodyString = ""; if (bodyStringBuffer.length() > 0) { bodyString = bodyStringBuffer.substring(0, bodyStringBuffer.length() - 1); } wr.writeBytes(bodyString); wr.flush(); wr.close(); br = new BufferedReader(new InputStreamReader(conn.getInputStream())); while ((line = br.readLine()) != null) { doc += line; } br.close(); logger.info("event=http_get url=" + urlString); } catch (Exception ex) { logger.error("event=http_get url=" + urlString, ex); } return doc; } }