metadata-profile-discovery/src/main/java/org/gcube/common/metadataprofilediscovery/reader/NamespaceCategoryReader.java

231 lines
7.7 KiB
Java

/**
*
*/
package org.gcube.common.metadataprofilediscovery.reader;
import static org.gcube.resources.discovery.icclient.ICFactory.client;
import java.io.ByteArrayInputStream;
import java.io.InputStream;
import java.io.StringReader;
import java.io.StringWriter;
import java.util.List;
import javax.xml.bind.JAXBContext;
import javax.xml.bind.Unmarshaller;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerException;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
import javax.xml.xpath.XPath;
import javax.xml.xpath.XPathConstants;
import javax.xml.xpath.XPathFactory;
import org.gcube.common.metadataprofilediscovery.jaxb.NamespaceCategories;
import org.gcube.common.resources.gcore.utils.XPathHelper;
import org.gcube.common.scope.impl.ScopeBean;
import org.gcube.resources.discovery.client.api.DiscoveryClient;
import org.gcube.resources.discovery.client.queries.api.Query;
import org.gcube.resources.discovery.client.queries.impl.QueryBox;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.w3c.dom.Document;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.xml.sax.InputSource;
/**
* The Class NamespaceCategoryReader.
*
* @author Francesco Mangiacrapa francesco.mangiacrapa@isti.cnr.it
* Apr 26, 2017
*/
public class NamespaceCategoryReader {
private static final String PATH_RESOURCE_PROFILE_BODY_NAMESPACES = "/Resource/Profile/Body/namespaces";
private static Logger logger = LoggerFactory.getLogger(NamespaceCategoryReader.class);
private static final String GENERIC_RESOURCE_NAMESPACES_NAME = "Namespaces Catalogue Categories";
private static final String GENERIC_RESOURCE_NAMESPACES_SECONDARY_TYPE = "DataCatalogueNamespace";
private ScopeBean scope;
private NamespaceCategories namespaces;
/**
* Instantiates a new medata format reader.
*
* @param scope the scope
* @throws Exception the exception
*/
public NamespaceCategoryReader(ScopeBean scope) throws Exception {
this.scope = scope;
readNamespaceCategory();
}
/**
* Gets the metadata format by id.
*
* @return the metadata format by id
* @throws Exception the exception
*/
private void readNamespaceCategory() throws Exception {
logger.trace("Getting Namespace Category");
if(this.scope==null)
throw new Exception("Scope is null");
String scopeString = this.scope.toString();
logger.trace("read scope: "+scopeString);
namespaces = new NamespaceCategories();
try {
logger.info("Using scope from ScopeProvider: "+scopeString);
String queryString = QueryForResourceUtil.getGcubeGenericQueryStringForSecondaryTypeAndName(GENERIC_RESOURCE_NAMESPACES_NAME, GENERIC_RESOURCE_NAMESPACES_SECONDARY_TYPE);
logger.trace("queryString: " +queryString);
Query q = new QueryBox(queryString);
DiscoveryClient<String> client = client();
List<String> appProfile = client.submit(q);
if (appProfile == null || appProfile.size() == 0)
throw new MetadataProfileNotFoundException("Your resource is not registered in the infrastructure, the scope is "+scopeString);
else {
String theResource = null;
try{
theResource = appProfile.get(0);
logger.debug("Resource "+GENERIC_RESOURCE_NAMESPACES_NAME+" found");
logger.trace("Resource "+GENERIC_RESOURCE_NAMESPACES_NAME+" is: "+theResource);
DocumentBuilder docBuilder = DocumentBuilderFactory.newInstance().newDocumentBuilder();
Document xmlDocument = docBuilder.parse(new InputSource(new StringReader(theResource)));
readNamespaceCategoryFromResource(xmlDocument);
}catch(Exception e){
logger.error("Error while parsing Resource "+theResource+" from the infrastructure, the scope is "+scopeString,e);
}
}
} catch (Exception e) {
logger.error("Error while trying to fetch resource with name " + GENERIC_RESOURCE_NAMESPACES_NAME + " and secondary type " + GENERIC_RESOURCE_NAMESPACES_SECONDARY_TYPE +
" from the infrastructure, the scope is "+scopeString, e);
throw new Exception("Error while trying to fetch resource with name " + GENERIC_RESOURCE_NAMESPACES_NAME + " and secondary type " + GENERIC_RESOURCE_NAMESPACES_SECONDARY_TYPE +
" from the infrastructure, the scope is "+scopeString, e);
} finally{
}
}
/**
* Read namespace category from resource.
*
* @param helper the helper
* @throws Exception the exception
*/
private void readNamespaceCategoryFromResource(Document xmlDocument) throws Exception{
try {
XPath xPath = XPathFactory.newInstance().newXPath();
String expression = PATH_RESOURCE_PROFILE_BODY_NAMESPACES;
NodeList nodeList = (NodeList) xPath.compile(expression).evaluate(xmlDocument, XPathConstants.NODESET);
String namespaceSources = getNodeString(nodeList.item(0));
JAXBContext jaxbContext = JAXBContext.newInstance(NamespaceCategories.class);
Unmarshaller jaxbUnmarshaller = jaxbContext.createUnmarshaller();
if(namespaceSources==null || namespaceSources.length()==0){
throw new Exception("Resource does not contain <namespaces> <namespace>...</namespace> </namespaces> in the body");
}
logger.debug("Unmarshalling document path "+PATH_RESOURCE_PROFILE_BODY_NAMESPACES +" to "+NamespaceCategories.class.getSimpleName());
InputStream stream = new ByteArrayInputStream(namespaceSources.getBytes());
namespaces = (NamespaceCategories) jaxbUnmarshaller.unmarshal(stream);
}catch(Exception e){
String error = "An error occurred in readNamespaceCategoryFromResource " + e.getMessage();
logger.error("An error occurred in readNamespaceCategoryFromResource ", e);
throw new Exception(error);
}
}
private String getNodeString(Node node) {
try {
StringWriter writer = new StringWriter();
Transformer transformer = TransformerFactory.newInstance().newTransformer();
transformer.transform(new DOMSource(node), new StreamResult(writer));
String output = writer.toString();
return output;
} catch (TransformerException e) {
e.printStackTrace();
}
return node.getTextContent();
}
/**
* Read namespace category from resource.
*
* @param helper the helper
* @throws Exception the exception
*/
private void readNamespaceCategoryFromResource(XPathHelper helper) throws Exception{
try {
if(helper==null) {
logger.warn("**************************\n\nXpathHelper is null!!!!\n\n");
}
List<String> namespaceSources = helper.evaluate(PATH_RESOURCE_PROFILE_BODY_NAMESPACES);
JAXBContext jaxbContext = JAXBContext.newInstance(NamespaceCategories.class);
Unmarshaller jaxbUnmarshaller = jaxbContext.createUnmarshaller();
if(namespaceSources==null || namespaceSources.size()==0){
throw new Exception("Resource does not contain <namespaces> <namespace>...</namespace> </namespaces> in the body");
}
InputStream stream = new ByteArrayInputStream(namespaceSources.get(0).getBytes());
namespaces = (NamespaceCategories) jaxbUnmarshaller.unmarshal(stream);
}catch(Exception e){
String error = "An error occurred in readNamespaceCategoryFromResource " + e.getMessage();
logger.error("An error occurred in readNamespaceCategoryFromResource ", e);
throw new Exception(error);
}
}
/**
* Gets the namespaces.
*
* @return the namespaces
*/
public NamespaceCategories getNamespaces() {
return namespaces;
}
/* (non-Javadoc)
* @see java.lang.Object#toString()
*/
@Override
public String toString() {
StringBuilder builder = new StringBuilder();
builder.append("NamespaceCategoryReader [scope=");
builder.append(scope);
builder.append(", namespaces=");
builder.append(namespaces);
builder.append("]");
return builder.toString();
}
}