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1   /**
2    * This file Copyright (c) 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.ui.dev;
35  
36  import info.magnolia.cms.util.ServletUtil;
37  
38  import java.io.IOException;
39  import java.lang.reflect.Field;
40  import java.util.Map;
41  
42  import javax.servlet.ServletException;
43  import javax.servlet.http.HttpServletRequest;
44  import javax.servlet.http.HttpServletResponse;
45  
46  import org.apache.commons.lang3.StringUtils;
47  import org.slf4j.Logger;
48  import org.slf4j.LoggerFactory;
49  
50  import com.vaadin.server.VaadinServlet;
51  
52  /**
53   * A {@link VaadinServlet} bypassing the internal Scss cache, to help working on Vaadin themes
54   * when provided in JAR files. This servlet should be used only for static resources,
55   * and mapped to <code>/VAADIN/*</code>.
56   */
57  public class NoScssCacheVaadinServlet extends VaadinServlet {
58      private static final Logger log = LoggerFactory.getLogger(NoScssCacheVaadinServlet.class);
59      private Map<String, Object> scssCache;
60  
61      @Override
62      protected void servletInitialized() throws ServletException {
63          super.servletInitialized();
64  
65          // Make self-internal scssCache dirtily accessible
66          try {
67              Field field = VaadinServlet.class.getDeclaredField("scssCache");
68              field.setAccessible(true);
69              scssCache = (Map<String, Object>) field.get(this);
70          } catch (ReflectiveOperationException e) {
71              log("Unable to initialize reference to inner Scss cache for the Vaadin servlet; caching won't be disabled.", e);
72          }
73      }
74  
75      @Override
76      protected void service(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
77          String requestURI = ServletUtil.stripPathParameters(request.getRequestURI());
78          if (StringUtils.endsWith(requestURI, ".css") && scssCache != null) {
79              scssCache.clear();
80          }
81  
82          super.service(request, response);
83      }
84  }