/**
* 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.license;
import java.io.IOException;
import java.io.OutputStreamWriter;
import java.io.UnsupportedEncodingException;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLConnection;
import java.net.URLEncoder;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.NoSuchElementException;
import org.apache.log4j.Logger;
import org.dspace.license.factory.LicenseServiceFactory;
import org.dspace.license.service.CreativeCommonsService;
import org.dspace.services.ConfigurationService;
import org.dspace.services.factory.DSpaceServicesFactory;
import org.jaxen.JaxenException;
import org.jaxen.jdom.JDOMXPath;
import org.jdom.Attribute;
import org.jdom.Document;
import org.jdom.Element;
import org.jdom.JDOMException;
import org.jdom.input.SAXBuilder;
/**
* A wrapper around Creative Commons REST web services.
*
* @author Wendy Bossons
*/
public class CCLookup {
/** log4j logger */
private static Logger log = Logger.getLogger(CCLookup.class);
private String cc_root;
private String jurisdiction;
private List<String> lcFilter = new ArrayList<String>();
private Document license_doc = null;
private String rdfString = null;
private String errorMessage = null;
private boolean success = false;
private SAXBuilder parser = new SAXBuilder();
private List<CCLicense> licenses = new ArrayList<CCLicense>();
private List<CCLicenseField> licenseFields = new ArrayList<CCLicenseField>();
protected CreativeCommonsService creativeCommonsService = LicenseServiceFactory.getInstance().getCreativeCommonsService();
/**
* Constructs a new instance with the default web services root.
*
*/
public CCLookup() {
super();
ConfigurationService configurationService = DSpaceServicesFactory.getInstance().getConfigurationService();
cc_root = configurationService.getProperty("cc.api.rooturl");
String jurisProp = configurationService.getProperty("cc.license.jurisdiction");
jurisdiction = (jurisProp != null) ? jurisProp : "";
String[] filters = configurationService.getArrayProperty("cc.license.classfilter");
if (filters != null) {
for (String name: filters) {
lcFilter.add(name.trim());
}
}
}
/**
* Returns the id for a particular CCLicense label. Returns an
* empty string if no match is found.
*
* @param class_label The CCLicense label to find.
* @return Returns a String containing the License class ID if the label
* is found; if not found, returns an empty string.
*
* @see CCLicense
*
*/
public String getLicenseId (String class_label) {
for (int i = 0; i < this.licenses.size(); i++) {
if ( ((CCLicense)this.licenses.get(i)).getLicenseName().equals(class_label)) {
return ( (CCLicense)this.licenses.get(i) ).getLicenseId();
}
}
return "";
}
/**
* Queries the web service for the available licenses.
*
* @param language The language to request labels and description strings in.
* @return Returns a Map of CCLicense objects.
*
* @see Map
* @see CCLicense
*
*/
public Collection<CCLicense> getLicenses(String language) {
// create XPath expressions
try {
JDOMXPath xp_Licenses = new JDOMXPath("//licenses/license");
JDOMXPath xp_LicenseID = new JDOMXPath("@id");
URL classUrl = new URL(this.cc_root + "/?locale=" + language);
Document classDoc = this.parser.build(classUrl);
// extract the identifiers and labels using XPath
List<Element> results = xp_Licenses.selectNodes(classDoc);
// populate licenses container
this.licenses.clear();
for (int i = 0; i < results.size(); i++) {
Element license = results.get(i);
// add if not filtered
String liD = ((Attribute)xp_LicenseID.selectSingleNode(license)).getValue();
if (! lcFilter.contains(liD)) {
this.licenses.add(new CCLicense(liD, license.getText(), i));
}
}
} catch (JaxenException jaxen_e) {
return null;
} catch (JDOMException jdom_e) {
return null;
} catch (IOException io_e) {
return null;
} catch (Exception e) {
// do nothing... but we should
return null;
}
return licenses;
}
/**
* Queries the web service for a set of licenseFields for a particular license class.
*
* @param license
* A String specifying the CCLicense identifier to
* retrieve fields for.
* @param language
* the locale string
* @return A Collection of LicenseField objects.
*
* @see CCLicense
*
*/
public Collection<CCLicenseField> getLicenseFields(String license, String language) {
JDOMXPath xp_LicenseField;
JDOMXPath xp_LicenseID;
JDOMXPath xp_FieldType;
JDOMXPath xp_Description;
JDOMXPath xp_Label;
JDOMXPath xp_Enum;
Document fieldDoc;
URL classUrl;
List results = null;
List enumOptions = null;
// create XPath expressions
try {
xp_LicenseField = new JDOMXPath("//field");
xp_LicenseID = new JDOMXPath("@id");
xp_Description = new JDOMXPath("description");
xp_Label = new JDOMXPath("label");
xp_FieldType = new JDOMXPath("type");
xp_Enum = new JDOMXPath("enum");
} catch (JaxenException e) {
return null;
}
// retrieve and parse the license class document
try {
classUrl = new URL(this.cc_root + "/license/" + license + "?locale=" + language);
} catch (Exception err) {
// do nothing... but we should
return null;
}
// parse the licenses document
try {
fieldDoc = this.parser.build(classUrl);
} catch (JDOMException e) {
return null;
} catch (IOException e) {
return null;
}
// reset the field definition container
this.licenseFields.clear();
// extract the identifiers and labels using XPath
try {
results = xp_LicenseField.selectNodes(fieldDoc);
} catch (JaxenException e) {
return null;
}
for (int i=0; i < results.size(); i++) {
Element field = (Element)results.get(i);
try {
// create the field object
CCLicenseField cclicensefield = new CCLicenseField(((Attribute)xp_LicenseID.selectSingleNode(field)).getValue(),
((Element)xp_Label.selectSingleNode(field)).getText() );
// extract additional properties
cclicensefield.setDescription( ((Element)xp_Description.selectSingleNode(field)).getText() );
cclicensefield.setType( ((Element)xp_FieldType.selectSingleNode(field)).getText() );
enumOptions = xp_Enum.selectNodes(field);
for (int j = 0; j < enumOptions.size(); j++) {
String id = ((Attribute)xp_LicenseID.selectSingleNode(enumOptions.get(j))).getValue();
String label =((Element)xp_Label.selectSingleNode(enumOptions.get(j))).getText();
cclicensefield.getEnum().put( id, label);
} // for each enum option
this.licenseFields.add(cclicensefield);
} catch (JaxenException e) {
return null;
}
}
return licenseFields;
} // licenseFields
/**
* Passes a set of "answers" to the web service and retrieves a license.
*
* @param licenseId The identifier of the license class being requested.
* @param answers A Map containing the answers to the license fields;
* each key is the identifier of a LicenseField, with the value
* containing the user-supplied answer.
* @param lang The language to request localized elements in.
*
* @throws IOException if IO error
*
* @see CCLicense
* @see Map
*/
public void issue(String licenseId, Map answers, String lang)
throws IOException{
// Determine the issue URL
String issueUrl = this.cc_root + "/license/" + licenseId + "/issue";
// Assemble the "answers" document
String answer_doc = "<answers>\n<locale>" + lang + "</locale>\n" + "<license-" + licenseId + ">\n";
Iterator keys = answers.keySet().iterator();
try {
String current = (String)keys.next();
while (true) {
answer_doc += "<" + current + ">" + (String)answers.get(current) + "</" + current + ">\n";
current = (String)keys.next();
}
} catch (NoSuchElementException e) {
// exception indicates we've iterated through the
// entire collection; just swallow and continue
}
// answer_doc += "<jurisdiction></jurisidiction>\n"; FAILS with jurisdiction argument
answer_doc += "</license-" + licenseId + ">\n</answers>\n";
String post_data;
try {
post_data = URLEncoder.encode("answers", "UTF-8") + "=" + URLEncoder.encode(answer_doc, "UTF-8");
} catch (UnsupportedEncodingException e) {
return;
}
URL post_url;
try {
post_url = new URL(issueUrl);
} catch (MalformedURLException e) {
return;
}
URLConnection connection = post_url.openConnection();
// this will not be needed after I'm done TODO: remove
connection.setDoOutput(true);
OutputStreamWriter writer = new OutputStreamWriter(connection.getOutputStream());
writer.write(post_data);
writer.flush();
// end TODO
try {
// parsing document from input stream
java.io.InputStream stream = connection.getInputStream();
this.license_doc = this.parser.build(stream);
} catch (JDOMException jde) {
log.warn(jde.getMessage());
} catch (Exception e) {
log.warn(e.getCause());
}
return;
} // issue
/**
* Passes a set of "answers" to the web service and retrieves a license.
*
* @param licenseURI The uri of the license.
*
* Note: does not support localization in 1.5 -- not yet
*
* @throws IOException if IO error
*
* @see CCLicense
* @see Map
*/
public void issue(String licenseURI)
throws IOException{
// Determine the issue URL
// Example: http://api.creativecommons.org/rest/1.5/details?
// license-uri=http://creativecommons.org/licenses/by-nc-sa/3.0/
String issueUrl = cc_root + "/details?license-uri=" + licenseURI;
URL request_url;
try {
request_url = new URL(issueUrl);
} catch (MalformedURLException e) {
return;
}
URLConnection connection = request_url.openConnection();
// this will not be needed after I'm done TODO: remove
connection.setDoOutput(true);
try {
// parsing document from input stream
java.io.InputStream stream = connection.getInputStream();
license_doc = this.parser.build(stream);
} catch (JDOMException jde) {
log.warn( jde.getMessage());
} catch (Exception e) {
log.warn(e.getCause());
}
return;
} // issue
/**
* Retrieves the URI for the license issued.
*
* @return A String containing the URI for the license issued.
*/
public String getLicenseUrl() {
String text = null;
try {
JDOMXPath xp_LicenseName = new JDOMXPath("//result/license-uri");
text = ((Element)xp_LicenseName.selectSingleNode(this.license_doc)).getText();
}
catch (Exception e) {
log.warn(e.getMessage());
setSuccess(false);
text = "An error occurred getting the license - uri.";
}
finally
{
return text;
}
} // getLicenseUrl
/**
* Retrieves the human readable name for the license issued.
*
* @return A String containing the license name.
*/
public String getLicenseName() {
String text = null;
try {
JDOMXPath xp_LicenseName = new JDOMXPath("//result/license-name");
text = ((Element)xp_LicenseName.selectSingleNode(this.license_doc)).getText();
}
catch (Exception e) {
log.warn(e.getMessage());
setSuccess(false);
text = "An error occurred on the license name.";
}
finally
{
return text;
}
} // getLicenseName
public org.jdom.Document getLicenseDocument() {
return this.license_doc;
}
public String getRdf()
throws IOException {
String result = "";
try {
result = creativeCommonsService.fetchLicenseRDF(license_doc);
} catch (Exception e) {
log.warn("An error occurred getting the rdf . . ." + e.getMessage() );
setSuccess(false);
}
return result;
}
public boolean isSuccess() {
setSuccess(false);
JDOMXPath xp_Success;
String text = null;
try {
xp_Success = new JDOMXPath("//message");
text = ((Element)xp_Success.selectSingleNode(this.license_doc)).getText();
setErrorMessage(text);
}
catch (Exception e) {
log.warn("There was an issue . . . " + text);
setSuccess(true);
}
return this.success;
}
private void setSuccess(boolean success) {
this.success = success;
}
public String getErrorMessage() {
return this.errorMessage;
}
private void setErrorMessage(String errorMessage) {
this.errorMessage = errorMessage;
}
}