[LMS-1492] configured caching

SVN: 15523

openbis/resource/server/web.xml

@@ -36,6 +36,15 @@
             ch.systemsx.cisd.openbis.generic.server.GenericHttpSessionListener
         </listener-class>
     </listener>
+    
+    <filter>
+        <filter-name>CacheFilter</filter-name>
+        <filter-class>ch.systemsx.cisd.openbis.generic.server.CacheFilter</filter-class>
+    </filter>
+    <filter-mapping>
+        <filter-name>CacheFilter</filter-name>
+        <url-pattern>/*</url-pattern>
+    </filter-mapping>
 
     <!-- Trying kind of extension (i.e., '*.do') here as 'url-pattern' does not work. -->
     <servlet-mapping>

openbis/source/java/ch/systemsx/cisd/openbis/generic/server/CacheFilter.java

+/*
+ * Copyright 2008 ETH Zuerich, CISD
+ *
+ * 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 ch.systemsx.cisd.openbis.generic.server;
+
+import java.io.IOException;
+
+import javax.servlet.Filter;
+import javax.servlet.FilterChain;
+import javax.servlet.FilterConfig;
+import javax.servlet.ServletException;
+import javax.servlet.ServletRequest;
+import javax.servlet.ServletResponse;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
+
+/**
+ * Implements {@link Filter} and sets the cache to store data for resources that don't have
+ * '.nocache.' in their name. Static resources such as images should stay in cache for a long time.
+ * 
+ * @author Piotr Buczek
+ */
+public class CacheFilter implements Filter
+{
+    @SuppressWarnings("unused")
+    private FilterConfig filterConfig;
+
+    private static final int DAY_IN_SECONDS = 24 * 60 * 60;
+
+    private static final int YEAR_IN_SECONDS = 365 * DAY_IN_SECONDS;
+
+    private static final int SPRINT_IN_SECONDS = 14 * DAY_IN_SECONDS;
+
+    public void doFilter(ServletRequest request, ServletResponse response, FilterChain filterChain)
+            throws IOException, ServletException
+    {
+
+        HttpServletRequest httpRequest = (HttpServletRequest) request;
+
+        String requestURI = httpRequest.getRequestURI();
+        if (requestURI.contains(".nocache.") == false)
+        {
+            HttpServletResponse httpResponse = (HttpServletResponse) response;
+            httpResponse.addHeader("Cache-Control", "max-age="
+                    + (isPicture(requestURI) ? YEAR_IN_SECONDS : SPRINT_IN_SECONDS));
+        }
+        filterChain.doFilter(request, response);
+
+    }
+
+    private boolean isPicture(String requestURI)
+    {
+        return requestURI.endsWith(".gif") || requestURI.endsWith(".png");
+    }
+
+    public void init(FilterConfig config) throws ServletException
+    {
+        this.filterConfig = config;
+    }
+
+    public void destroy()
+    {
+        this.filterConfig = null;
+    }
+}