001 /*
002 * Copyright 1999,2004 The Apache Software Foundation.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 * http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016
017 package org.apache.commons.feedparser.locate.blogservice;
018
019 import org.apache.commons.feedparser.FeedParserException;
020 import org.apache.commons.feedparser.locate.*;
021
022 /**
023 * Models the Flickr image blog service, encapsulating whether a given weblog
024 * is this type of service and where it usually keeps its feeds.
025 *
026 * @author Brad Neuberg, bkn3@columbia.edu
027 */
028 public class Flickr extends BlogService {
029
030 /** Returns whether we can trust the results of this blog service's
031 * autodiscovery links. For example, TextAmerica returns invalid
032 * autodiscovery results.
033 */
034 public boolean hasValidAutoDiscovery() {
035 return true;
036 }
037
038 /** Returns whether we should follow HTTP redirects for this blog service.
039 * Some services don't implement HTTP redirects correctly, while others,
040 * like Xanga, require it.
041 */
042 public boolean followRedirects() {
043 return false;
044 }
045
046 /** Determines if the weblog at the given resource and with the given
047 * content is this blog service.
048 * @param resource A full URI to this resource, such as
049 * "http://www.codinginparadise.org".
050 * @param content The full HTML content at the resource's URL.
051 * @throws FeedParserException Thrown if an error occurs while
052 * determining the type of this weblog.
053 */
054 public boolean isThisService(String resource, String content)
055 throws FeedParserException {
056 return resource.indexOf( "flickr.com" ) != -1;
057 }
058
059 /**
060 * Returns an array of FeedReferences that contains information on the
061 * usual locations this blog service contains its feed. The feeds should
062 * be ordered by quality, so that higher quality feeds come before lower
063 * quality ones (i.e. you would want to have an Atom FeedReference
064 * object come before an RSS 0.91 FeedReference object in this list).
065 * @param resource A URL to the given weblog that might be used to build
066 * up where feeds are usually located.
067 * @param content The full content of the resource URL, which might
068 * be useful to determine where feeds are usually located. This can be
069 * null.
070 * @throws FeedParserException Thrown if an error occurs while trying
071 * to determine the usual locations of feeds for this service.
072 */
073 public FeedReference[] getFeedLocations(String resource,
074 String content)
075 throws FeedParserException {
076 resource = getBaseFeedPath(resource);
077 // * Input: http://flickr.com/photos/tags/cats/
078 // *
079 // * Output: http://flickr.com/services/feeds/photos_public.gne?tags=cats&format=atom_03
080
081 if ( resource == null )
082 return new FeedReference[0];
083
084 int begin = resource.indexOf( "/tags/" );
085
086 //we can't continue here.
087 if ( begin == -1 )
088 return new FeedReference[0];
089
090 begin += 6;
091
092 int end = resource.lastIndexOf( "/" );
093 if ( end == -1 || end < begin )
094 end = resource.length();
095
096 String tag = resource.substring( begin, end );
097
098 String location = "http://flickr.com/services/feeds/photos_public.gne?tags=" +
099 tag +
100 "&format=atom_03";
101
102 FeedReference flickrLocations[] =
103 { new FeedReference(location,
104 FeedReference.ATOM_MEDIA_TYPE) };
105
106 return flickrLocations;
107 }
108 }