/*
* Copyright 2013 Brian Thomas Matthews
*
* Licensed 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 com.btmatthews.maven.plugins.ldap.dsml;
import com.btmatthews.maven.plugins.ldap.FormatReader;
import com.unboundid.ldap.sdk.Attribute;
import com.unboundid.ldif.LDIFAddChangeRecord;
import com.unboundid.ldif.LDIFChangeRecord;
import org.dom4j.Document;
import org.dom4j.DocumentException;
import org.dom4j.Node;
import org.dom4j.io.SAXReader;
import org.jaxen.JaxenException;
import org.jaxen.NamespaceContext;
import org.jaxen.SimpleNamespaceContext;
import org.jaxen.XPath;
import org.jaxen.dom4j.Dom4jXPath;
import java.io.IOException;
import java.io.InputStream;
import java.util.*;
/**
* A {@link FormatReader} that reads LDAP directory entries from a DSML file.
*
* @author <a href="mailto:brian@btmatthews.com">Brian Matthews</a>
* @since 1.2.0
*/
public final class DSMLFormatReader implements FormatReader {
/**
* Iterates over the directory entries extracted from the .dsml file.
*/
private final Iterator<Node> entryIterator;
/**
* The namespace context maps the dsml prefix to the http://www.dsml.org/DSML namespace.
*/
private final NamespaceContext namespaceContext;
/**
* The {@link XPath} expression used to iterate through the object classes for the DSML entry.
*/
private final XPath objectClassXPath;
/**
* The {@link XPath} expression used to iterate through the attribute for the DSML entry.
*/
private final XPath attrXPath;
/**
* The {@link XPath} expression used to iterate through the values of each attribute for the DSML entry.
*/
private final XPath attrValueXPath;
/**
* Initialise the reader to read DSML entries from an underlying input stream.
*
* @param inputStream The underlying input stream.
* @throws DocumentException If there was a problem parsing the DSML file.
* @throws JaxenException If there was a problem creating the {@link XPath} expressions.
* @throws IOException If there was a problem reading the DSML file.
*/
public DSMLFormatReader(final InputStream inputStream) throws DocumentException, IOException, JaxenException {
final Map<String, String> map = new HashMap<String, String>();
map.put("dsml", "http://www.dsml.org/DSML");
namespaceContext = new SimpleNamespaceContext(map);
final SAXReader reader = new SAXReader();
final Document document = reader.read(inputStream);
final XPath xpath = createXPath("/dsml[namespace-uri()='http://www.dsml.org/DSML']/dsml:directory-entries/dsml:entry");
objectClassXPath = createXPath("dsml:objectclass/dsml:oc-value");
attrXPath = createXPath("dsml:attr");
attrValueXPath = createXPath("dsml:value");
final List<Node> entries = (List<Node>) xpath.selectNodes(document);
entryIterator = entries.iterator();
}
/**
* Read the next change record from the underlying input stream.
*
* @return The next change record or {@code null} if the end of the input stream has been reached.
*/
@Override
public LDIFChangeRecord nextRecord() {
if (entryIterator.hasNext()) {
try {
final Node entryNode = entryIterator.next();
final String dn = entryNode.valueOf("@dn");
final List<Attribute> attributes = new ArrayList<Attribute>();
final List<Node> objectClassList = (List<Node>) objectClassXPath.selectNodes(entryNode);
final String[] objectClasses = new String[objectClassList.size()];
for (int j = 0; j < objectClasses.length; ++j) {
objectClasses[j] = objectClassList.get(j).getStringValue();
}
attributes.add(new Attribute("objectclass", objectClasses));
for (final Node attributeNode : (List<Node>) attrXPath.selectNodes(entryNode)) {
final String attributeName = attributeNode.valueOf("@name");
final List<Node> attributeValueNodes = (List<Node>) attrValueXPath.selectNodes(attributeNode);
switch (attributeValueNodes.size()) {
case 0:
break;
case 1: {
final String attributeValue = attributeValueNodes.get(0).getStringValue();
attributes.add(new Attribute(attributeName, attributeValue));
break;
}
default: {
final String[] attributeValues = new String[attributeValueNodes.size()];
for (int j = 0; j < attributeValueNodes.size(); ++j) {
attributeValues[j] = attributeValueNodes.get(j).getStringValue();
}
attributes.add(new Attribute(attributeName, attributeValues));
break;
}
}
}
return new LDIFAddChangeRecord(dn, attributes);
} catch (final JaxenException e) {
return null;
}
} else {
return null;
}
}
/**
* Called to close {@link DSMLFormatReader}.
*/
@Override
public void close() {
}
/**
* Create a {@link XPath} for the expression {@code xpathString}.
*
* @param xpathString The expression.
* @return The {@link XPath}.
* @throws JaxenException If there was a problem parsing the {@code xpathString} expression.
*/
private XPath createXPath(final String xpathString) throws JaxenException {
final XPath xpath = new Dom4jXPath(xpathString);
xpath.setNamespaceContext(namespaceContext);
return xpath;
}
}