/* 
    P/P   *  Method: net.sourceforge.pebble.web.action.ResponseFeedAction__static_init
          */
     1  /*
     2   * Copyright (c) 2003-2006, Simon Brown
     3   * All rights reserved.
     4   *
     5   * Redistribution and use in source and binary forms, with or without
     6   * modification, are permitted provided that the following conditions are met:
     7   *
     8   *   - Redistributions of source code must retain the above copyright
     9   *     notice, this list of conditions and the following disclaimer.
    10   *
    11   *   - Redistributions in binary form must reproduce the above copyright
    12   *     notice, this list of conditions and the following disclaimer in
    13   *     the documentation and/or other materials provided with the
    14   *     distribution.
    15   *
    16   *   - Neither the name of Pebble nor the names of its contributors may
    17   *     be used to endorse or promote products derived from this software
    18   *     without specific prior written permission.
    19   *
    20   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
    21   * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
    22   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
    23   * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
    24   * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
    25   * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
    26   * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
    27   * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
    28   * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
    29   * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
    30   * POSSIBILITY OF SUCH DAMAGE.
    31   */
    32  package net.sourceforge.pebble.web.action;
    33  
    34  import net.sourceforge.pebble.Constants;
    35  import net.sourceforge.pebble.domain.*;
    36  import net.sourceforge.pebble.web.view.NotModifiedView;
    37  import net.sourceforge.pebble.web.view.View;
    38  import net.sourceforge.pebble.web.view.impl.*;
    39  
         /* 
    P/P   *  Method: void net.sourceforge.pebble.web.action.ResponseFeedAction()
          */
    40  import javax.servlet.ServletException;
    41  import javax.servlet.http.HttpServletRequest;
    42  import javax.servlet.http.HttpServletResponse;
    43  import java.text.SimpleDateFormat;
    44  import java.util.*;
    45  
    46  /**
    47   * Gets a feed (RSS or Atom) for blog entry responses.
    48   *
    49   * @author    Simon Brown
    50   */
    51  public class ResponseFeedAction extends Action {
    52  
    53    /**
    54     * Peforms the processing associated with this action.
    55     *
    56     * @param request  the HttpServletRequest instance
    57     * @param response the HttpServletResponse instance
    58     * @return the name of the next view
    59     */
    60    public View process(HttpServletRequest request, HttpServletResponse response) throws ServletException {
             /* 
    P/P       *  Method: View process(HttpServletRequest, HttpServletResponse)
              * 
              *  Preconditions:
              *    request != null
              *    response != null
              *    this.model != null
              *    this.model.data != null
              * 
              *  Presumptions:
              *    java.util.HashMap:get(...)@63 != null
              *    java.util.Iterator:next(...)@98 != null
              *    init'ed(java.util.Locale.ENGLISH)
              *    net.sourceforge.pebble.domain.Blog:getLastModified(...)@76 != null
              *    net.sourceforge.pebble.domain.BlogEntry:getResponses(...)@98 != null
              * 
              *  Postconditions:
              *    return_value in Addr_Set{&new NotModifiedView(process#5),&new NotModifiedView(process#7),&new AtomResponsesView(process#12),&new RssResponsesView(process#13)}
              *    new AtomResponsesView(process#12) num objects <= 1
              *    new NotModifiedView(process#5) num objects <= 1
              *    new NotModifiedView(process#7) num objects <= 1
              *    new RssResponsesView(process#13) num objects <= 1
              * 
              *  Test Vectors:
              *    java.lang.String:equals(...)@80: {0}, {1}
              *    java.lang.String:equals(...)@82: {0}, {1}
              *    java.lang.String:equalsIgnoreCase(...)@122: {0}, {1}
              *    java.lang.String:equalsIgnoreCase(...)@70: {0}, {1}
              *    javax.servlet.http.HttpServletRequest:getHeader(...)@67: Addr_Set{null}, Inverse{null}
              *    javax.servlet.http.HttpServletRequest:getHeader(...)@68: Addr_Set{null}, Inverse{null}
              *    javax.servlet.http.HttpServletRequest:getParameter(...)@62: Addr_Set{null}, Inverse{null}
              *    javax.servlet.http.HttpServletRequest:getParameter(...)@87: Addr_Set{null}, Inverse{null}
              *    net.sourceforge.pebble.domain.BlogEntry:isPublished(...)@96: {0}, {1}
              *    net.sourceforge.pebble.domain.BlogService:getBlogEntry(...)@92: Addr_Set{null}, Inverse{null}
              *    ...
              */
    61      Blog blog = (Blog)getModel().get(Constants.BLOG_KEY);
    62      String flavor = request.getParameter("flavor");
    63  
    64      SimpleDateFormat httpFormat = new SimpleDateFormat("EEE, dd MMM yyyy HH:mm:ss z");
    65      httpFormat.setTimeZone(TimeZone.getTimeZone("GMT"));
    66  
    67      String ifModifiedSince = request.getHeader("If-Modified-Since");
    68      String ifNoneMatch = request.getHeader("If-None-Match");
    69  
    70      if (flavor != null && flavor.equalsIgnoreCase("atom")) {
    71        response.setContentType("application/atom+xml; charset=" + blog.getCharacterEncoding());
    72      } else {
    73        response.setContentType("application/xml; charset=" + blog.getCharacterEncoding());
    74      }
    75  
    76      Date lastModified = blog.getLastModified();
    77      response.setDateHeader("Last-Modified", lastModified.getTime());
    78      response.setHeader("ETag", "\"" + httpFormat.format(lastModified) + "\"");
    79  
    80      if (ifModifiedSince != null && ifModifiedSince.equals(httpFormat.format(lastModified))) {
    81        return new NotModifiedView();
    82      } else if (ifNoneMatch != null && ifNoneMatch.equals("\"" + httpFormat.format(lastModified) + "\"")) {
    83        return new NotModifiedView();
    84      } else {
    85        List responses = new ArrayList();
    86  
    87        String entryId = request.getParameter("entry");
    88        if (entryId != null) {
    89          BlogService service = new BlogService();
    90          BlogEntry blogEntry = null;
    91          try {
    92            blogEntry = service.getBlogEntry(blog, entryId);
    93          } catch (BlogServiceException e) {
    94            throw new ServletException(e);
    95          }
    96          if (blogEntry != null && blogEntry.isPublished()) {
    97            getModel().put(Constants.BLOG_ENTRY_KEY, blogEntry);
    98            for (Response r : blogEntry.getResponses()) {
    99              if (r.isApproved()) {
   100                responses.add(r);
   101              }
   102            }
   103          }
   104        } else {
   105          responses = new ArrayList(blog.getRecentApprovedResponses());
   106        }
   107  
   108        int numberOfResponses = blog.getRecentResponsesOnHomePage();
   109  
   110        if (responses.size() > numberOfResponses) {
   111          responses = responses.subList(0, numberOfResponses);
   112        }
   113  
   114        getModel().put(Constants.RESPONSES, responses);
   115  
   116        // set the locale of this feed request to be English
   117        javax.servlet.jsp.jstl.core.Config.set(
   118            request,
   119            javax.servlet.jsp.jstl.core.Config.FMT_LOCALE,
   120            Locale.ENGLISH);
   121  
   122        if (flavor != null && flavor.equalsIgnoreCase("atom")) {
   123          return new AtomResponsesView();
   124        } else {
   125          return new RssResponsesView();
   126        }
   127      }
   128    }
   129  
   130    /**
   131     * Helper method to find a named tag from a request parameter.
   132     *
   133     * @param abstractBlog      the blog for which the feed is for
   134     * @param request   the HTTP request containing the tag parameter
   135     * @return  a Tag instance, or null if the tag isn't
   136     *          specified or can't be found
   137     */
   138    private Tag getTag(AbstractBlog abstractBlog, HttpServletRequest request) {
             /* 
    P/P       *  Method: Tag getTag(AbstractBlog, HttpServletRequest)
              * 
              *  Preconditions:
              *    (soft) request != null
              * 
              *  Postconditions:
              *    return_value in Addr_Set{null,&new Tag(getTag#1)}
              *    new Tag(getTag#1) num objects <= 1
              * 
              *  Test Vectors:
              *    javax.servlet.http.HttpServletRequest:getParameter(...)@145: Addr_Set{null}, Inverse{null}
              */
   139      if (abstractBlog instanceof MultiBlog) {
   140        // getting tag based, aggregated feed isn't supported
   141        return null;
   142      } else {
   143        Blog blog = (Blog)abstractBlog;
   144  
   145        String tag = request.getParameter("tag");
   146        if (tag != null) {
   147          return new Tag(tag, blog);
   148        } else {
   149          return null;
   150        }
   151      }
   152    }
   153  
   154    /**
   155     * Helper method to find a named category from a request parameter.
   156     *
   157     * @param abstractBlog      the blog for which the feed is for
   158     * @param request   the HTTP request containing the category parameter
   159     * @return  a Category instance, or null if the category isn't
   160     *          specified or can't be found
   161     */
   162    private Category getCategory(AbstractBlog abstractBlog, HttpServletRequest request) {
             /* 
    P/P       *  Method: Category getCategory(AbstractBlog, HttpServletRequest)
              * 
              *  Preconditions:
              *    (soft) abstractBlog != null
              *    (soft) request != null
              * 
              *  Postconditions:
              *    init'ed(return_value)
              * 
              *  Test Vectors:
              *    javax.servlet.http.HttpServletRequest:getParameter(...)@169: Addr_Set{null}, Inverse{null}
              */
   163      if (abstractBlog instanceof MultiBlog) {
   164        // getting Category based, aggregated feed isn't supported
   165        return null;
   166      } else {
   167        Blog blog = (Blog)abstractBlog;
   168  
   169        String categoryId = request.getParameter("category");
   170        if (categoryId != null) {
   171          return blog.getCategory(categoryId);
   172        } else {
   173          return null;
   174        }
   175      }
   176    }
   177  
   178  }