src/java/ZKGrailsPageFilter.java

   1 /*
   2  * Copyright 2004-2005 the original author or authors.
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at
   7  *
   8  *      http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16 // package org.codehaus.groovy.grails.web.sitemesh;
  17
  18 import com.opensymphony.module.sitemesh.Decorator;
  19 import com.opensymphony.module.sitemesh.DecoratorMapper;
  20 import com.opensymphony.module.sitemesh.Page;
  21 import com.opensymphony.module.sitemesh.util.Container;
  22 import com.opensymphony.module.sitemesh.filter.PageFilter;
  23 import com.opensymphony.module.sitemesh.filter.PageResponseWrapper;
  24 import org.apache.commons.logging.Log;
  25 import org.apache.commons.logging.LogFactory;
  26 import org.codehaus.groovy.grails.web.servlet.GrailsApplicationAttributes;
  27 import org.codehaus.groovy.grails.commons.ConfigurationHolder;
  28 import org.springframework.web.util.UrlPathHelper;
  29
  30 import org.codehaus.groovy.grails.web.sitemesh.FactoryHolder;
  31
  32 import javax.servlet.*;
  33 import javax.servlet.http.HttpServletRequest;
  34 import javax.servlet.http.HttpServletResponse;
  35 import java.io.IOException;
  36 import java.io.PrintWriter;
  37
  38 /**
  39  * Extends the default page filter to overide the apply decorator behaviour
  40  * if the page is a GSP
  41  *
  42  * @author Graeme Rocher
  43  * @since Apr 19, 2006
  44  */
  45 public class ZKGrailsPageFilter extends PageFilter {
  46
  47         private static final Log LOG = LogFactory.getLog( ZKGrailsPageFilter.class );
  48     private static final String HTML_EXT = ".html";
  49     private static final String UTF_8_ENCODING = "UTF-8";
  50     private static final String CONFIG_OPTION_GSP_ENCODING = "grails.views.gsp.encoding";
  51
  52
  53     public void init(FilterConfig filterConfig) {
  54                 super.init(filterConfig);
  55                 this.filterConfig = filterConfig;
  56         FactoryHolder.setFactory(this.factory);
  57     }
  58
  59     public void destroy() {
  60         super.destroy();
  61         FactoryHolder.setFactory(null);
  62     }
  63
  64     private boolean isZK(HttpServletRequest request) {
  65         String path = extractRequestPath(request);
  66         final String[] ext = new String[]{".zul",".dsp","*.zhtml", "*.svg", "*.xml2html"};
  67         for(int i=0;i < ext.length; i++) {
  68                 if(path.lastIndexOf(ext[i])!=-1) return true;
  69         }
  70         return false;
  71     }
  72     /*
  73      * TODO: This method has been copied from the parent to fix a bug in sitemesh 2.3. When sitemesh 2.4 is release this method and the two private methods below can removed
  74
  75      * Main method of the Filter.
  76      *
  77      * <p>Checks if the Filter has been applied this request. If not, parses the page
  78      * and applies {@link com.opensymphony.module.sitemesh.Decorator} (if found).
  79      */
  80     public void doFilter(ServletRequest rq, ServletResponse rs, FilterChain chain)
  81             throws IOException, ServletException {
  82
  83         HttpServletRequest request = (HttpServletRequest) rq;
  84
  85                 // System.out.println(">>> " + extractRequestPath(request));
  86
  87         if (rq.getAttribute(FILTER_APPLIED) != null || factory.isPathExcluded(extractRequestPath(request)) || isZK(request)) {
  88             // ensure that filter is only applied once per request
  89             chain.doFilter(rq, rs);
  90         }
  91         else {
  92             request.setAttribute(FILTER_APPLIED, Boolean.TRUE);
  93
  94             factory.refresh();
  95             DecoratorMapper decoratorMapper = factory.getDecoratorMapper();
  96             HttpServletResponse response = (HttpServletResponse) rs;
  97
  98             // parse data into Page object (or continue as normal if Page not parseable)
  99             Page page = parsePage(request, response, chain);
 100
 101             if (page != null) {
 102                 page.setRequest(request);
 103
 104                 Decorator decorator = decoratorMapper.getDecorator(request, page);
 105                 if (decorator != null && decorator.getPage() != null) {
 106                     applyDecorator(page, decorator, request, response);
 107                     return;
 108                 }
 109                 // if we got here, an exception occured or the decorator was null,
 110                 // what we don't want is an exception printed to the user, so
 111                 // we write the original page
 112                 writeOriginal(request, response, page);
 113             }
 114         }
 115     }
 116
 117     /**
 118      * Continue in filter-chain, writing all content to buffer and parsing
 119      * into returned {@link com.opensymphony.module.sitemesh.Page} object. If
 120      * {@link com.opensymphony.module.sitemesh.Page} is not parseable, null is returned.
 121      */
 122     protected Page parsePage(HttpServletRequest request, HttpServletResponse response, FilterChain chain) throws IOException, ServletException {
 123         try {
 124             PageResponseWrapper pageResponse = new PageResponseWrapper(response, factory);
 125             UrlPathHelper urlHelper = new UrlPathHelper();
 126             String requestURI = urlHelper.getOriginatingRequestUri(request);
 127             // static content?
 128             if(requestURI.endsWith(HTML_EXT))    {
 129                 String encoding = (String)ConfigurationHolder.getFlatConfig().get(CONFIG_OPTION_GSP_ENCODING);
 130                 if(encoding == null) encoding = UTF_8_ENCODING;
 131                 pageResponse.setContentType("text/html;charset="+encoding);
 132             }
 133
 134
 135
 136             chain.doFilter(request, pageResponse);
 137             // check if another servlet or filter put a page object to the request
 138             Page result = (Page)request.getAttribute(PAGE);
 139             if (result == null) {
 140                 // parse the page
 141                 result = pageResponse.getPage();
 142             }
 143             request.setAttribute(USING_STREAM, pageResponse.isUsingStream() ? Boolean.TRUE : Boolean.FALSE); // JDK 1.3 friendly
 144             return result;
 145         }
 146         catch (IllegalStateException e) {
 147             // weblogic throws an IllegalStateException when an error page is served.
 148             // it's ok to ignore this, however for all other containers it should be thrown
 149             // properly.
 150             if (Container.get() != Container.WEBLOGIC) throw e;
 151             return null;
 152         }
 153     }
 154
 155     private String extractRequestPath(HttpServletRequest request) {
 156         String servletPath = request.getServletPath();
 157         String pathInfo = request.getPathInfo();
 158         String query = request.getQueryString();
 159         return (servletPath == null ? "" : servletPath)
 160                 + (pathInfo == null ? "" : pathInfo)
 161                 + (query == null ? "" : ("?" + query));
 162     }
 163
 164     /** Write the original page data to the response. */
 165     private void writeOriginal(HttpServletRequest request, HttpServletResponse response, Page page) throws IOException {
 166         response.setContentLength(page.getContentLength());
 167         if (request.getAttribute(USING_STREAM).equals(Boolean.TRUE))
 168         {
 169             PrintWriter writer = new PrintWriter(response.getOutputStream());
 170             page.writePage(writer);
 171             //flush writer to underlying outputStream
 172             writer.flush();
 173             response.getOutputStream().flush();
 174         }
 175         else
 176         {
 177             page.writePage(response.getWriter());
 178             response.getWriter().flush();
 179         }
 180     }
 181
 182
 183     /* (non-Javadoc)
 184          * @see com.opensymphony.module.sitemesh.filter.PageFilter#applyDecorator(com.opensymphony.module.sitemesh.Page, com.opensymphony.module.sitemesh.Decorator, javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse)
 185          */
 186         protected void applyDecorator(Page page, Decorator decorator, HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
 187         final String uriPath = decorator.getURIPath();
 188         if(uriPath != null && uriPath.endsWith(".gsp")) {
 189                 request.setAttribute(PAGE, page);
 190
 191             detectContentTypeFromPage(page, response);
 192
 193             RequestDispatcher rd = request.getRequestDispatcher(decorator.getURIPath());
 194             if(!response.isCommitted()) {
 195                 if(LOG.isDebugEnabled()) {
 196                         LOG.debug("Rendering layout using forward: " + decorator.getURIPath());
 197                 }
 198                 rd.forward(request, response);
 199             }
 200             else {
 201                 if(LOG.isDebugEnabled()) {
 202                         LOG.debug("Rendering layout using include: " + decorator.getURIPath());
 203                 }
 204                 request.setAttribute(GrailsApplicationAttributes.GSP_TO_RENDER,decorator.getURIPath());
 205                 rd.include(request,response);
 206                 request.removeAttribute(GrailsApplicationAttributes.GSP_TO_RENDER);
 207             }
 208
 209             // set the headers specified as decorator init params
 210             while (decorator.getInitParameterNames().hasNext()) {
 211                 String initParam = (String) decorator.getInitParameterNames().next();
 212                 if (initParam.startsWith("header.")) {
 213                     response.setHeader(initParam.substring(initParam.indexOf('.')), decorator.getInitParameter(initParam));
 214                 }
 215             }
 216             request.removeAttribute(PAGE);
 217         }
 218         else {
 219
 220                 super.applyDecorator(page, decorator, request, response);
 221
 222         }
 223         }
 224
 225     private void detectContentTypeFromPage(Page page, HttpServletResponse response) {
 226         String contentType = page.getProperty("meta.http-equiv.Content-Type");
 227         if(contentType != null && "text/html".equals(response.getContentType())) {
 228             response.setContentType(contentType);
 229         }
 230     }
 231
 232 }