1 /** 2 * This file Copyright (c) 2015-2018 Magnolia International 3 * Ltd. (http://www.magnolia-cms.com). All rights reserved. 4 * 5 * 6 * This file is dual-licensed under both the Magnolia 7 * Network Agreement and the GNU General Public License. 8 * You may elect to use one or the other of these licenses. 9 * 10 * This file is distributed in the hope that it will be 11 * useful, but AS-IS and WITHOUT ANY WARRANTY; without even the 12 * implied warranty of MERCHANTABILITY or FITNESS FOR A 13 * PARTICULAR PURPOSE, TITLE, or NONINFRINGEMENT. 14 * Redistribution, except as permitted by whichever of the GPL 15 * or MNA you select, is prohibited. 16 * 17 * 1. For the GPL license (GPL), you can redistribute and/or 18 * modify this file under the terms of the GNU General 19 * Public License, Version 3, as published by the Free Software 20 * Foundation. You should have received a copy of the GNU 21 * General Public License, Version 3 along with this program; 22 * if not, write to the Free Software Foundation, Inc., 51 23 * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 24 * 25 * 2. For the Magnolia Network Agreement (MNA), this file 26 * and the accompanying materials are made available under the 27 * terms of the MNA which accompanies this distribution, and 28 * is available at http://www.magnolia-cms.com/mna.html 29 * 30 * Any modifications to this file must keep this entire header 31 * intact. 32 * 33 */ 34 package info.magnolia.module.ui; 35 36 import info.magnolia.cms.util.ClasspathResourcesUtil; 37 38 import java.io.IOException; 39 import java.io.InputStream; 40 41 import javax.servlet.ServletOutputStream; 42 import javax.servlet.http.HttpServlet; 43 import javax.servlet.http.HttpServletRequest; 44 import javax.servlet.http.HttpServletResponse; 45 46 import org.apache.commons.io.IOUtils; 47 import org.slf4j.Logger; 48 import org.slf4j.LoggerFactory; 49 50 /** 51 * This is a _very_ primitive servlet that serves resources off of the classpath. It does absolutely no error checking 52 * or anything of the sort - it is expected we are in control of the install web resources and as such need no help. 53 * *Do not use this servlet in any other context than Magnolia's installation UI !* 54 */ 55 public class InstallationResourcesServlet extends HttpServlet { 56 private final static Logger log = LoggerFactory.getLogger(InstallationResourcesServlet.class); 57 private final long constructionTimestamp; 58 59 public InstallationResourcesServlet() { 60 constructionTimestamp = System.currentTimeMillis(); 61 } 62 63 @Override 64 protected long getLastModified(HttpServletRequest req) { 65 // All requests will have the same Last-Modified for the lifetime of the servlet. 66 // It's safe to assume a restart of the server could mean the resources have changed, but we don't need anything 67 // more specific than that, and we can thus rely on the default service() implementation. 68 return constructionTimestamp; 69 } 70 71 @Override 72 public void doGet(HttpServletRequest req, HttpServletResponse res) throws IOException { 73 final String resourcePath = req.getPathInfo(); 74 try (final InputStream in = ClasspathResourcesUtil.getStream(resourcePath); 75 final ServletOutputStream out = res.getOutputStream()) { 76 if (in == null) { 77 throw new IllegalStateException("No resource found at " + resourcePath); 78 } 79 IOUtils.copy(in, out); 80 out.flush(); 81 } catch (IOException e) { 82 // only log at debug level 83 // tomcat usually throws a ClientAbortException anytime the user stop loading the page 84 log.debug("Unable to spool resource due to {}", e, e); 85 if (!res.isCommitted()) { 86 res.sendError(HttpServletResponse.SC_INTERNAL_SERVER_ERROR); 87 } 88 } 89 } 90 91 }