/** * The contents of this file are subject to the license and copyright * detailed in the LICENSE and NOTICE files at the root of the source * tree and available online at * * http://www.dspace.org/license/ */ package org.dspace.app.util; import java.io.IOException; import java.util.ArrayList; import java.util.Date; import java.util.List; import java.util.Map; import javax.servlet.http.HttpServletRequest; import org.apache.commons.lang.ArrayUtils; import org.apache.commons.lang.StringUtils; import org.dspace.content.*; import org.dspace.content.factory.ContentServiceFactory; import org.dspace.content.service.CollectionService; import org.dspace.content.service.CommunityService; import org.dspace.content.service.ItemService; import org.dspace.core.Context; import org.dspace.handle.factory.HandleServiceFactory; import org.w3c.dom.Document; import org.dspace.core.ConfigurationManager; import org.dspace.core.Constants; import com.sun.syndication.feed.synd.SyndFeed; import com.sun.syndication.feed.synd.SyndFeedImpl; import com.sun.syndication.feed.synd.SyndEntry; import com.sun.syndication.feed.synd.SyndEntryImpl; import com.sun.syndication.feed.synd.SyndEnclosure; import com.sun.syndication.feed.synd.SyndEnclosureImpl; import com.sun.syndication.feed.synd.SyndImage; import com.sun.syndication.feed.synd.SyndImageImpl; import com.sun.syndication.feed.synd.SyndPerson; import com.sun.syndication.feed.synd.SyndPersonImpl; import com.sun.syndication.feed.synd.SyndContent; import com.sun.syndication.feed.synd.SyndContentImpl; import com.sun.syndication.feed.module.DCModuleImpl; import com.sun.syndication.feed.module.DCModule; import com.sun.syndication.feed.module.Module; import com.sun.syndication.feed.module.itunes.*; import com.sun.syndication.feed.module.itunes.types.Duration; import com.sun.syndication.io.SyndFeedOutput; import com.sun.syndication.io.FeedException; import org.apache.log4j.Logger; import org.dspace.services.ConfigurationService; import org.dspace.services.factory.DSpaceServicesFactory; /** * Invoke ROME library to assemble a generic model of a syndication * for the given list of Items and scope. Consults configuration for the * metadata bindings to feed elements. Uses ROME's output drivers to * return any of the implemented formats, e.g. RSS 1.0, RSS 2.0, ATOM 1.0. * * The feed generator and OpenSearch call on this class so feed contents are * uniform for both. * * @author Larry Stone */ public class SyndicationFeed { protected final Logger log = Logger.getLogger(SyndicationFeed.class); /** i18n key values */ public static final String MSG_UNTITLED = "notitle"; public static final String MSG_LOGO_TITLE = "logo.title"; public static final String MSG_FEED_TITLE = "feed.title"; public static final String MSG_FEED_DESCRIPTION = "general-feed.description"; public static final String MSG_METADATA = "metadata."; public static final String MSG_UITYPE = "ui.type"; // UI keywords public static final String UITYPE_XMLUI = "xmlui"; public static final String UITYPE_JSPUI = "jspui"; // default DC fields for entry protected String defaultTitleField = "dc.title"; protected String defaultAuthorField = "dc.contributor.author"; protected String defaultDateField = "dc.date.issued"; private static final String[] defaultDescriptionFields = new String[]{"dc.description.abstract", "dc.description", "dc.title.alternative", "dc.title"}; protected String defaultExternalMedia = "dc.source.uri"; private final ConfigurationService configurationService = DSpaceServicesFactory.getInstance().getConfigurationService(); // metadata field for Item title in entry: protected String titleField = configurationService.getProperty("webui.feed.item.title", defaultTitleField); // metadata field for Item publication date in entry: protected String dateField = configurationService.getProperty("webui.feed.item.date", defaultDateField); // metadata field for Item description in entry: private static final String descriptionFields[] = DSpaceServicesFactory.getInstance().getConfigurationService().getArrayProperty("webui.feed.item.description", defaultDescriptionFields); protected String authorField = configurationService.getProperty("webui.feed.item.author", defaultAuthorField); // metadata field for Podcast external media source url protected String externalSourceField = configurationService.getProperty("webui.feed.podcast.sourceuri", defaultExternalMedia); // metadata field for Item dc:creator field in entry's DCModule (no default) protected String dcCreatorField = configurationService.getProperty("webui.feed.item.dc.creator"); // metadata field for Item dc:date field in entry's DCModule (no default) protected String dcDateField = configurationService.getProperty("webui.feed.item.dc.date"); // metadata field for Item dc:author field in entry's DCModule (no default) protected String dcDescriptionField = configurationService.getProperty("webui.feed.item.dc.description"); // List of available mimetypes that we'll add to podcast feed. Multiple values separated by commas protected String[] podcastableMIMETypes = configurationService.getArrayProperty("webui.feed.podcast.mimetypes", new String[]{"audio/x-mpeg"}); // -------- Instance variables: // the feed object we are building protected SyndFeed feed = null; // memory of UI that called us, "xmlui" or "jspui" // affects Bitstream retrieval URL and I18N keys protected String uiType = null; protected HttpServletRequest request = null; protected CollectionService collectionService; protected CommunityService communityService; protected ItemService itemService; /** * Constructor. * @param ui either "xmlui" or "jspui" */ public SyndicationFeed(String ui) { feed = new SyndFeedImpl(); uiType = ui; ContentServiceFactory contentServiceFactory = ContentServiceFactory.getInstance(); itemService = contentServiceFactory.getItemService(); collectionService = contentServiceFactory.getCollectionService(); communityService = contentServiceFactory.getCommunityService(); } /** * Returns list of metadata selectors used to compose the description element * * @return selector list - format 'schema.element[.qualifier]' */ public static String[] getDescriptionSelectors() { return (String[]) ArrayUtils.clone(descriptionFields); } /** * Fills in the feed and entry-level metadata from DSpace objects. * @param request request * @param context context * @param dso DSpaceObject * @param items array of objects * @param labels label map */ public void populate(HttpServletRequest request, Context context, DSpaceObject dso, List items, Map labels) { String logoURL = null; String objectURL = null; String defaultTitle = null; boolean podcastFeed = false; this.request = request; // dso is null for the whole site, or a search without scope if (dso == null) { defaultTitle = ConfigurationManager.getProperty("dspace.name"); feed.setDescription(localize(labels, MSG_FEED_DESCRIPTION)); objectURL = resolveURL(request, null); logoURL = ConfigurationManager.getProperty("webui.feed.logo.url"); } else { Bitstream logo = null; if (dso.getType() == Constants.COLLECTION) { Collection col = (Collection)dso; defaultTitle = col.getName(); feed.setDescription(collectionService.getMetadata(col, "short_description")); logo = col.getLogo(); String cols = ConfigurationManager.getProperty("webui.feed.podcast.collections"); if(cols != null && cols.length() > 1 && cols.contains(col.getHandle()) ) { podcastFeed = true; } } else if (dso.getType() == Constants.COMMUNITY) { Community comm = (Community)dso; defaultTitle = comm.getName(); feed.setDescription(communityService.getMetadata(comm, "short_description")); logo = comm.getLogo(); String comms = ConfigurationManager.getProperty("webui.feed.podcast.communities"); if(comms != null && comms.length() > 1 && comms.contains(comm.getHandle()) ){ podcastFeed = true; } } objectURL = resolveURL(request, dso); if (logo != null) { logoURL = urlOfBitstream(request, logo); } } feed.setTitle(labels.containsKey(MSG_FEED_TITLE) ? localize(labels, MSG_FEED_TITLE) : defaultTitle); feed.setLink(objectURL); feed.setPublishedDate(new Date()); feed.setUri(objectURL); // add logo if we found one: if (logoURL != null) { // we use the path to the logo for this, the logo itself cannot // be contained in the rdf. Not all RSS-viewers show this logo. SyndImage image = new SyndImageImpl(); image.setLink(objectURL); if (StringUtils.isNotBlank(feed.getTitle())) { image.setTitle(feed.getTitle()); } else { image.setTitle(localize(labels, MSG_LOGO_TITLE)); } image.setUrl(logoURL); feed.setImage(image); } // add entries for items if (items != null) { List entries = new ArrayList(); for (DSpaceObject itemDSO : items) { if (itemDSO.getType() != Constants.ITEM) { continue; } Item item = (Item)itemDSO; boolean hasDate = false; SyndEntry entry = new SyndEntryImpl(); entries.add(entry); String entryURL = resolveURL(request, item); entry.setLink(entryURL); entry.setUri(entryURL); String title = getOneDC(item, titleField); entry.setTitle(title == null ? localize(labels, MSG_UNTITLED) : title); // "published" date -- should be dc.date.issued String pubDate = getOneDC(item, dateField); if (pubDate != null) { entry.setPublishedDate((new DCDate(pubDate)).toDate()); hasDate = true; } // date of last change to Item entry.setUpdatedDate(item.getLastModified()); StringBuffer db = new StringBuffer(); for (String df : descriptionFields) { // Special Case: "(date)" in field name means render as date boolean isDate = df.indexOf("(date)") > 0; if (isDate) { df = df.replaceAll("\\(date\\)", ""); } List dcv = itemService.getMetadataByMetadataString(item, df); if (dcv.size() > 0) { String fieldLabel = labels.get(MSG_METADATA + df); if (fieldLabel != null && fieldLabel.length()>0) { db.append(fieldLabel).append(": "); } boolean first = true; for (MetadataValue v : dcv) { if (first) { first = false; } else { db.append("; "); } db.append(isDate ? new DCDate(v.getValue()).toString() : v.getValue()); } db.append("\n"); } } if (db.length() > 0) { SyndContent desc = new SyndContentImpl(); desc.setType("text/plain"); desc.setValue(db.toString()); entry.setDescription(desc); } // This gets the authors into an ATOM feed List authors = itemService.getMetadataByMetadataString(item, authorField); if (authors.size() > 0) { List creators = new ArrayList(); for (MetadataValue author : authors) { SyndPerson sp = new SyndPersonImpl(); sp.setName(author.getValue()); creators.add(sp); } entry.setAuthors(creators); } // only add DC module if any DC fields are configured if (dcCreatorField != null || dcDateField != null || dcDescriptionField != null) { DCModule dc = new DCModuleImpl(); if (dcCreatorField != null) { List dcAuthors = itemService.getMetadataByMetadataString(item, dcCreatorField); if (dcAuthors.size() > 0) { List creators = new ArrayList(); for (MetadataValue author : dcAuthors) { creators.add(author.getValue()); } dc.setCreators(creators); } } if (dcDateField != null && !hasDate) { List v = itemService.getMetadataByMetadataString(item, dcDateField); if (v.size() > 0) { dc.setDate((new DCDate(v.get(0).getValue())).toDate()); } } if (dcDescriptionField != null) { List v = itemService.getMetadataByMetadataString(item, dcDescriptionField); if (v.size() > 0) { StringBuffer descs = new StringBuffer(); for (MetadataValue d : v) { if (descs.length() > 0) { descs.append("\n\n"); } descs.append(d.getValue()); } dc.setDescription(descs.toString()); } } entry.getModules().add(dc); } //iTunes Podcast Support - START if (podcastFeed) { // Add enclosure(s) List enclosures = new ArrayList(); try { List bunds = itemService.getBundles(item, "ORIGINAL"); if (bunds.get(0) != null) { List bits = bunds.get(0).getBitstreams(); for (Bitstream bit : bits) { String mime = bit.getFormat(context).getMIMEType(); if (ArrayUtils.contains(podcastableMIMETypes,mime)) { SyndEnclosure enc = new SyndEnclosureImpl(); enc.setType(bit.getFormat(context).getMIMEType()); enc.setLength(bit.getSizeBytes()); enc.setUrl(urlOfBitstream(request, bit)); enclosures.add(enc); } else { continue; } } } //Also try to add an external value from dc.identifier.other // We are assuming that if this is set, then it is a media file List externalMedia = itemService.getMetadataByMetadataString(item, externalSourceField); if(externalMedia.size() > 0) { for (MetadataValue anExternalMedia : externalMedia) { SyndEnclosure enc = new SyndEnclosureImpl(); enc.setType("audio/x-mpeg"); //We can't determine MIME of external file, so just picking one. enc.setLength(1); enc.setUrl(anExternalMedia.getValue()); enclosures.add(enc); } } } catch (Exception e) { System.out.println(e.getMessage()); } entry.setEnclosures(enclosures); // Get iTunes specific fields: author, subtitle, summary, duration, keywords EntryInformation itunes = new EntryInformationImpl(); String author = getOneDC(item, authorField); if (author != null && author.length() > 0) { itunes.setAuthor(author); // } itunes.setSubtitle(title == null ? localize(labels, MSG_UNTITLED) : title); // if (db.length() > 0) { itunes.setSummary(db.toString()); // } String extent = getOneDC(item, "dc.format.extent"); // assumed that user will enter this field with length of song in seconds if (extent != null && extent.length() > 0) { extent = extent.split(" ")[0]; Integer duration = Integer.parseInt(extent); itunes.setDuration(new Duration(duration)); // } String subject = getOneDC(item, "dc.subject"); if (subject != null && subject.length() > 0) { String[] subjects = new String[1]; subjects[0] = subject; itunes.setKeywords(subjects); // } entry.getModules().add(itunes); } } feed.setEntries(entries); } } /** * Sets the feed type for XML delivery, e.g. "rss_1.0", "atom_1.0" * Must match one of ROME's configured generators, see rome.properties * (currently rss_1.0, rss_2.0, atom_1.0, atom_0.3) * @param feedType feed type */ public void setType(String feedType) { feed.setFeedType(feedType); // XXX FIXME: workaround ROME 1.0 bug, it puts invalid image element in rss1.0 if ("rss_1.0".equals(feedType)) { feed.setImage(null); } } /** * @return the feed we built as DOM Document * @throws FeedException if feed error */ public Document outputW3CDom() throws FeedException { try { SyndFeedOutput feedWriter = new SyndFeedOutput(); return feedWriter.outputW3CDom(feed); } catch (FeedException e) { log.error(e); throw e; } } /** * @return the feed we built as serialized XML string * @throws FeedException if feed error */ public String outputString() throws FeedException { SyndFeedOutput feedWriter = new SyndFeedOutput(); return feedWriter.outputString(feed); } /** * send the output to designated Writer * @param writer Writer * @throws FeedException if feed error * @throws IOException if IO error */ public void output(java.io.Writer writer) throws FeedException, IOException { SyndFeedOutput feedWriter = new SyndFeedOutput(); feedWriter.output(feed, writer); } /** * Add a ROME plugin module (e.g. for OpenSearch) at the feed level. * @param m module */ public void addModule(Module m) { feed.getModules().add(m); } // utility to get config property with default value when not set. protected static String getDefaultedConfiguration(String key, String dfl) { String result = ConfigurationManager.getProperty(key); return (result == null) ? dfl : result; } // returns absolute URL to download content of bitstream (which might not belong to any Item) protected String urlOfBitstream(HttpServletRequest request, Bitstream logo) { String name = logo.getName(); return resolveURL(request,null) + (uiType.equalsIgnoreCase(UITYPE_XMLUI) ?"/bitstream/id/":"/retrieve/") + logo.getID()+"/"+(name == null?"":name); } protected String baseURL = null; // cache the result for null /** * Return a url to the DSpace object, either use the official * handle for the item or build a url based upon the current server. * * If the dspaceobject is null then a local url to the repository is generated. * * @param request current servlet request * @param dso The object to reference, null if to the repository. * @return URL */ protected String resolveURL(HttpServletRequest request, DSpaceObject dso) { // If no object given then just link to the whole repository, // since no offical handle exists so we have to use local resolution. if (dso == null) { if (baseURL == null) { if (request == null) { baseURL = ConfigurationManager.getProperty("dspace.url"); } else { baseURL = (request.isSecure()) ? "https://" : "http://"; baseURL += ConfigurationManager.getProperty("dspace.hostname"); baseURL += ":" + request.getServerPort(); baseURL += request.getContextPath(); } } return baseURL; } // return a link to handle in repository else if (ConfigurationManager.getBooleanProperty("webui.feed.localresolve")) { return resolveURL(request, null) + "/handle/" + dso.getHandle(); } // link to the Handle server or other persistent URL source else { return HandleServiceFactory.getInstance().getHandleService().getCanonicalForm(dso.getHandle()); } } // retrieve text for localization key, or mark untranslated protected String localize(Map labels, String s) { return labels.containsKey(s) ? labels.get(s) : ("Untranslated:"+s); } // spoonful of syntactic sugar when we only need first value protected String getOneDC(Item item, String field) { List dcv = itemService.getMetadataByMetadataString(item, field); return (dcv.size() > 0) ? dcv.get(0).getValue() : null; } }