/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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 feed;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.OutputStreamWriter;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;
import org.apache.abdera.Abdera;
import org.apache.abdera.factory.Factory;
import org.apache.abdera.model.Document;
import org.apache.abdera.model.Entry;
import org.apache.abdera.model.Feed;
import org.apache.abdera.model.Person;
import org.apache.abdera.parser.Parser;
import org.apache.tuscany.sca.binding.atom.collection.Collection;
import org.apache.tuscany.sca.binding.atom.collection.NotFoundException;
import org.osoa.sca.annotations.Property;
import org.osoa.sca.annotations.Reference;
import com.sun.syndication.feed.synd.SyndFeed;
import com.sun.syndication.io.SyndFeedOutput;
/**
* Implementation of an SCA component that aggregates several
* Atom and RSS feeds.
*
* @version $Rev: 1025503 $ $Date: 2010-10-20 12:22:15 +0100 (Wed, 20 Oct 2010) $
*/
public class AggregatorImpl implements org.apache.tuscany.sca.binding.atom.collection.Collection {
@Reference(required = false)
public Collection atomFeed1;
@Reference(required = false)
public Collection atomFeed2;
@Reference(required = false)
public org.apache.tuscany.sca.binding.rss.collection.Collection rssFeed1;
@Reference(required = false)
public org.apache.tuscany.sca.binding.rss.collection.Collection rssFeed2;
@Reference(required = false)
public Sort sort;
@Property
public String feedTitle = "Aggregated Feed";
@Property
public String feedDescription = "Anonymous Aggregated Feed";
@Property
public String feedAuthor = "anonymous";
public Feed getFeed() {
// Create a new Feed
Factory factory = Abdera.getNewFactory();
Feed feed = factory.newFeed();
feed.setTitle(feedTitle);
feed.setSubtitle(feedDescription);
Person author = factory.newAuthor();
author.setName(feedAuthor);
feed.addAuthor(author);
feed.addLink("http://tuscany.apache.org/", "alternate");
// Aggregate entries from atomFeed1, atomFeed2, rssFeed1 and rssFeed2
List<Entry> entries = new ArrayList<Entry>();
if (atomFeed1 != null) {
try {
entries.addAll(atomFeed1.getFeed().getEntries());
} catch (Exception e) {
int x = 0;
}
}
if (atomFeed2 != null) {
try {
entries.addAll(atomFeed2.getFeed().getEntries());
} catch (Exception e) {
int x = 0;
}
}
if (rssFeed1 != null) {
try {
entries.addAll(atomFeed(rssFeed1.getFeed()).getEntries());
} catch (Exception e) {
int x = 0;
}
}
if (rssFeed2 != null) {
try {
entries.addAll(atomFeed(rssFeed2.getFeed()).getEntries());
} catch (Exception e) {
int x = 0;
}
}
// Sort entries by updated date
if (sort != null) {
entries = sort.sort(entries);
}
// Add the entries to the new feed
// Also synthesize a feed id and updated field base on entries
Date feedUpdated = new Date( 0 );
for (Entry entry: entries) {
Date entryUpdated = entry.getUpdated();
if (( entryUpdated != null ) && ( entryUpdated.compareTo( feedUpdated ) > 0 )) {
feedUpdated = entryUpdated;
}
feed.addEntry(entry);
}
feed.setUpdated( feedUpdated );
// Note that feed id should be permanent, immutable, and unique
// in order to support proper ETag creation.
// Tough to do when the feed is regenerated with each get.
feed.setId( "http://tuscany.apache.org/feed", true );
return feed;
}
public Feed query(String queryString) {
Factory factory = Abdera.getNewFactory();
Feed feed = factory.newFeed();
feed.setTitle(feedTitle);
feed.setSubtitle(feedDescription);
Person author = factory.newAuthor();
author.setName(feedAuthor);
feed.addAuthor(author);
feed.addLink("http://tuscany.apache.org", "alternate");
Feed allFeed = getFeed();
if (queryString.startsWith("title=")) {
String title = queryString.substring(6);
for (Entry entry: allFeed.getEntries()) {
if (entry.getTitle().contains(title)) {
feed.addEntry(entry);
}
}
}
return feed;
}
public void delete(String id) throws NotFoundException {
}
public Entry get(String id) throws NotFoundException {
return null;
}
public Entry post(Entry entry) {
return null;
}
public void put(String id, Entry entry) throws NotFoundException {
}
/**
* Convert a ROME feed to an Abdera feed.
*
* @param romeFeed
* @return
*/
private static Feed atomFeed(SyndFeed syndFeed) {
ByteArrayOutputStream bos = new ByteArrayOutputStream();
syndFeed.setFeedType("atom_1.0");
SyndFeedOutput syndOutput = new SyndFeedOutput();
try {
syndOutput.output(syndFeed, new OutputStreamWriter(bos, "UTF-8"));
} catch (Exception e) {
throw new RuntimeException(e);
}
Parser parser = Abdera.getNewParser();
Document<Feed> document = parser.parse(new ByteArrayInputStream(bos.toByteArray()));
return document.getRoot();
}
}