/*
* StructBuilder.java
*
* Copyright (c) 2006, Imperial College. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* - Neither the name of Imperial College nor the names of their
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
* TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
* USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
* DAMAGE.
*/
package org.dspace.administer;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.sql.SQLException;
import java.util.Enumeration;
import java.util.Hashtable;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.transform.TransformerException;
import org.apache.commons.cli.CommandLine;
import org.apache.commons.cli.CommandLineParser;
import org.apache.commons.cli.Options;
import org.apache.commons.cli.PosixParser;
import org.apache.xpath.XPathAPI;
import org.dspace.authorize.AuthorizeException;
import org.dspace.content.Collection;
import org.dspace.content.Community;
import org.dspace.core.Context;
import org.dspace.eperson.EPerson;
import org.jdom.Element;
import org.jdom.output.XMLOutputter;
import org.w3c.dom.Document;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.xml.sax.SAXException;
/**
* This class deals with importing community and collection structures from
* an XML file.
*
* The XML file structure needs to be:
*
* <import_structure>
* <community>
* <name>....</name>
* <community>...</community>
* <collection>
* <name>....</name>
* </collection>
* </community>
* </import_structure>
*
* it can be arbitrarily deep, and supports all the metadata elements
* that make up the community and collection metadata. See the system
* documentation for more details
*
* @author Richard Jones
*
*/
public class StructBuilder
{
/** the output xml document which will contain updated information about the
* imported structure
*/
private static org.jdom.Document xmlOutput = new org.jdom.Document(new Element("imported_structure"));
/** a hashtable to hold metadata for the collection being worked on */
private static Hashtable collectionMap = new Hashtable();
/** a hashtable to hold metadata for the community being worked on */
private static Hashtable communityMap = new Hashtable();
/**
* Main method to be run from the command line to import a structure into
* DSpace
*
* This is of the form:
*
* StructBuilder -f [xml source] -e [administrator email] -o [output file]
*
* The output file will contain exactly the same as the source xml document, but
* with the handle for each imported item added as an attribute.
*/
public static void main(String[] argv)
throws Exception
{
CommandLineParser parser = new PosixParser();
Options options = new Options();
options.addOption( "f", "file", true, "file");
options.addOption( "e", "eperson", true, "eperson");
options.addOption("o", "output", true, "output");
CommandLine line = parser.parse( options, argv );
String file = null;
String eperson = null;
String output = null;
if (line.hasOption('f'))
{
file = line.getOptionValue('f');
}
if (line.hasOption('e'))
{
eperson = line.getOptionValue('e');
}
if (line.hasOption('o'))
{
output = line.getOptionValue('o');
}
if (output == null || eperson == null || file == null)
{
usage();
System.exit(0);
}
// create a context
Context context = new Context();
// set the context
context.setCurrentUser(EPerson.findByEmail(context, eperson));
// load the XML
Document document = loadXML(file);
// run the preliminary validation, to be sure that the the XML document
// is properly structured
validate(document);
// load the mappings into the member variable hashmaps
communityMap.put("name", "name");
communityMap.put("description", "short_description");
communityMap.put("intro", "introductory_text");
communityMap.put("copyright", "copyright_text");
communityMap.put("sidebar", "side_bar_text");
collectionMap.put("name", "name");
collectionMap.put("description", "short_description");
collectionMap.put("intro", "introductory_text");
collectionMap.put("copyright", "copyright_text");
collectionMap.put("sidebar", "side_bar_text");
collectionMap.put("license", "license");
collectionMap.put("provenance", "provenance_description");
// get the top level community list
NodeList first = XPathAPI.selectNodeList(document, "/import_structure/community");
// run the import starting with the top level communities
Element[] elements = handleCommunities(context, first, null);
// generate the output
Element root = xmlOutput.getRootElement();
for (int i = 0; i < elements.length; i++)
{
root.addContent(elements[i]);
}
// finally write the string into the output file
try
{
BufferedWriter out = new BufferedWriter(new FileWriter(output));
out.write(new XMLOutputter().outputString(xmlOutput));
out.close();
}
catch (IOException e)
{
System.out.println("Unable to write to output file " + output);
System.exit(0);
}
context.complete();
}
/**
* Output the usage information
*/
private static void usage()
{
System.out.println("Usage: java StructBuilder -f <source XML file> -o <output file> -e <eperson email>");
System.out.println("Communitities will be created from the top level, and a map of communities to handles will be returned in the output file");
return;
}
/**
* Validate the XML document. This method does not return, but if validation
* fails it generates an error and ceases execution
*
* @param document the XML document object
* @throws TransformerException
*
*/
private static void validate(org.w3c.dom.Document document)
throws TransformerException
{
StringBuffer err = new StringBuffer();
boolean trip = false;
err.append("The following errors were encountered parsing the source XML\n");
err.append("No changes have been made to the DSpace instance\n\n");
NodeList first = XPathAPI.selectNodeList(document, "/import_structure/community");
if (first.getLength() == 0)
{
err.append("-There are no top level communities in the source document");
System.out.println(err.toString());
System.exit(0);
}
String errs = validateCommunities(first, 1);
if (errs != null)
{
err.append(errs);
trip = true;
}
if (trip)
{
System.out.println(err.toString());
System.exit(0);
}
}
/**
* Validate the communities section of the XML document. This returns a string
* containing any errors encountered, or null if there were no errors
*
* @param communities the NodeList of communities to validate
* @param level the level in the XML document that we are at, for the purposes
* of error reporting
*
* @return the errors that need to be generated by the calling method, or null if
* no errors.
*/
private static String validateCommunities(NodeList communities, int level)
throws TransformerException
{
StringBuffer err = new StringBuffer();
boolean trip = false;
String errs = null;
for (int i = 0; i < communities.getLength(); i++)
{
Node n = communities.item(i);
NodeList name = XPathAPI.selectNodeList(n, "name");
if (name.getLength() != 1)
{
String pos = Integer.toString(i + 1);
err.append("-The level " + level + " community in position " + pos);
err.append(" does not contain exactly one name field\n");
trip = true;
}
// validate sub communities
NodeList subCommunities = XPathAPI.selectNodeList(n, "community");
String comErrs = validateCommunities(subCommunities, level + 1);
if (comErrs != null)
{
err.append(comErrs);
trip = true;
}
// validate collections
NodeList collections = XPathAPI.selectNodeList(n, "collection");
String colErrs = validateCollections(collections, level + 1);
if (colErrs != null)
{
err.append(colErrs);
trip = true;
}
}
if (trip)
{
errs = err.toString();
}
return errs;
}
/**
* validate the collection section of the XML document. This generates a
* string containing any errors encountered, or returns null if no errors
*
* @param collections a NodeList of collections to validate
* @param level the level in the XML document for the purposes of error reporting
*
* @return the errors to be generated by the calling method, or null if none
*/
private static String validateCollections(NodeList collections, int level)
throws TransformerException
{
StringBuffer err = new StringBuffer();
boolean trip = false;
String errs = null;
for (int i = 0; i < collections.getLength(); i++)
{
Node n = collections.item(i);
NodeList name = XPathAPI.selectNodeList(n, "name");
if (name.getLength() != 1)
{
String pos = Integer.toString(i + 1);
err.append("-The level " + level + " collection in position " + pos);
err.append(" does not contain exactly one name field\n");
trip = true;
}
}
if (trip)
{
errs = err.toString();
}
return errs;
}
/**
* Load in the XML from file.
*
* @param filename
* the filename to load from
*
* @return the DOM representation of the XML file
*/
private static org.w3c.dom.Document loadXML(String filename)
throws IOException, ParserConfigurationException, SAXException
{
DocumentBuilder builder = DocumentBuilderFactory.newInstance()
.newDocumentBuilder();
org.w3c.dom.Document document = builder.parse(new File(filename));
return document;
}
/**
* Return the String value of a Node
*
* @param node the node from which we want to extract the string value
*
* @return the string value of the node
*/
public static String getStringValue(Node node)
{
String value = node.getNodeValue();
if (node.hasChildNodes())
{
Node first = node.getFirstChild();
if (first.getNodeType() == Node.TEXT_NODE)
{
return first.getNodeValue().trim();
}
}
return value;
}
/**
* Take a node list of communities and build the structure from them, delegating
* to the relevant methods in this class for sub-communities and collections
*
* @param context the context of the request
* @param communities a nodelist of communities to create along with their subjstructures
* @param parent the parent community of the nodelist of communities to create
*
* @return an element array containing additional information regarding the
* created communities (e.g. the handles they have been assigned)
*/
private static Element[] handleCommunities(Context context, NodeList communities, Community parent)
throws TransformerException, SQLException, Exception
{
Element[] elements = new Element[communities.getLength()];
for (int i = 0; i < communities.getLength(); i++)
{
Community community;
Element element = new Element("community");
// create the community or sub community
if (parent != null)
{
community = parent.createSubcommunity();
}
else
{
community = Community.create(null, context);
}
// default the short description to be an empty string
community.setMetadata("short_description", " ");
// now update the metadata
Node tn = communities.item(i);
Enumeration keys = communityMap.keys();
while (keys.hasMoreElements())
{
Node node = null;
String key = (String) keys.nextElement();
NodeList nl = XPathAPI.selectNodeList(tn, key);
if (nl.getLength() == 1)
{
node = nl.item(0);
community.setMetadata((String) communityMap.get(key), getStringValue(node));
}
}
// FIXME: at the moment, if the community already exists by name
// then this will throw a PSQLException on a duplicate key
// violation
// Ideally we'd skip this row and continue to create sub
// communities
// and so forth where they don't exist, but it's proving
// difficult
// to isolate the community that already exists without hitting
// the database directly.
community.update();
// build the element with the handle that identifies the new
// community
// along with all the information that we imported here
// This looks like a lot of repetition of getting information
// from above
// but it's here to keep it separate from the create process in
// case
// we want to move it or make it switchable later
element.setAttribute("identifier", community.getHandle());
Element nameElement = new Element("name");
nameElement.setText(community.getMetadata("name"));
element.addContent(nameElement);
if (community.getMetadata("short_description") != null)
{
Element descriptionElement = new Element("description");
descriptionElement.setText(community.getMetadata("short_description"));
element.addContent(descriptionElement);
}
if (community.getMetadata("introductory_text") != null)
{
Element introElement = new Element("intro");
introElement.setText(community.getMetadata("introductory_text"));
element.addContent(introElement);
}
if (community.getMetadata("copyright_text") != null)
{
Element copyrightElement = new Element("copyright");
copyrightElement.setText(community.getMetadata("copyright_text"));
element.addContent(copyrightElement);
}
if (community.getMetadata("side_bar_text") != null)
{
Element sidebarElement = new Element("sidebar");
sidebarElement.setText(community.getMetadata("side_bar_text"));
element.addContent(sidebarElement);
}
// handle sub communities
NodeList subCommunities = XPathAPI.selectNodeList(tn, "community");
Element[] subCommunityElements = handleCommunities(context, subCommunities, community);
// handle collections
NodeList collections = XPathAPI.selectNodeList(tn, "collection");
Element[] collectionElements = handleCollections(context, collections, community);
int j;
for (j = 0; j < subCommunityElements.length; j++)
{
element.addContent(subCommunityElements[j]);
}
for (j = 0; j < collectionElements.length; j++)
{
element.addContent(collectionElements[j]);
}
elements[i] = element;
}
return elements;
}
/**
* Take a node list of collections and create the structure from them
*
* @param context the context of the request
* @param collections the node list of collections to be created
* @param parent the parent community to whom the collections belong
*
* @return an Element array containing additional information about the
* created collections (e.g. the handle)
*/
private static Element[] handleCollections(Context context, NodeList collections, Community parent)
throws TransformerException, SQLException, AuthorizeException, IOException, Exception
{
Element[] elements = new Element[collections.getLength()];
for (int i = 0; i < collections.getLength(); i++)
{
Element element = new Element("collection");
Collection collection = parent.createCollection();
// default the short description to the empty string
collection.setMetadata("short_description", " ");
// import the rest of the metadata
Node tn = collections.item(i);
Enumeration keys = collectionMap.keys();
while (keys.hasMoreElements())
{
Node node = null;
String key = (String) keys.nextElement();
NodeList nl = XPathAPI.selectNodeList(tn, key);
if (nl.getLength() == 1)
{
node = nl.item(0);
collection.setMetadata((String) collectionMap.get(key), getStringValue(node));
}
}
collection.update();
element.setAttribute("identifier", collection.getHandle());
Element nameElement = new Element("name");
nameElement.setText(collection.getMetadata("name"));
element.addContent(nameElement);
if (collection.getMetadata("short_description") != null)
{
Element descriptionElement = new Element("description");
descriptionElement.setText(collection.getMetadata("short_description"));
element.addContent(descriptionElement);
}
if (collection.getMetadata("introductory_text") != null)
{
Element introElement = new Element("intro");
introElement.setText(collection.getMetadata("introductory_text"));
element.addContent(introElement);
}
if (collection.getMetadata("copyright_text") != null)
{
Element copyrightElement = new Element("copyright");
copyrightElement.setText(collection.getMetadata("copyright_text"));
element.addContent(copyrightElement);
}
if (collection.getMetadata("side_bar_text") != null)
{
Element sidebarElement = new Element("sidebar");
sidebarElement.setText(collection.getMetadata("side_bar_text"));
element.addContent(sidebarElement);
}
if (collection.getMetadata("license") != null)
{
Element sidebarElement = new Element("license");
sidebarElement.setText(collection.getMetadata("license"));
element.addContent(sidebarElement);
}
if (collection.getMetadata("provenance_description") != null)
{
Element sidebarElement = new Element("provenance");
sidebarElement.setText(collection.getMetadata("provenance_description"));
element.addContent(sidebarElement);
}
elements[i] = element;
}
return elements;
}
}