/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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 org.apache.synapse.mediators.xquery;
import net.sf.saxon.javax.xml.xquery.*;
import net.sf.saxon.xqj.SaxonXQDataSource;
import org.apache.axiom.om.OMElement;
import org.apache.axiom.om.OMNode;
import org.apache.axiom.om.OMText;
import org.apache.axiom.om.impl.builder.StAXOMBuilder;
import org.apache.axiom.om.impl.dom.DOOMAbstractFactory;
import org.apache.axiom.om.util.ElementHelper;
import org.apache.synapse.MessageContext;
import org.apache.synapse.SynapseException;
import org.apache.synapse.SynapseLog;
import org.apache.synapse.util.xpath.SourceXPathSupport;
import org.apache.synapse.util.xpath.SynapseXPath;
import org.apache.synapse.config.Entry;
import org.apache.synapse.config.SynapseConfigUtils;
import org.apache.synapse.mediators.AbstractMediator;
import org.apache.synapse.mediators.MediatorProperty;
import org.w3c.dom.Element;
import org.xml.sax.InputSource;
import javax.xml.namespace.QName;
import javax.xml.stream.XMLInputFactory;
import javax.xml.stream.XMLStreamException;
import javax.xml.transform.dom.DOMSource;
import javax.activation.DataHandler;
import java.io.StringReader;
import java.io.InputStream;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
/**
* The XQueryMediator provides the means to extract and manipulate data from XML documents using
* XQuery . It is possible to query against the current SOAP Message or external XML. To query
* against the current SOAP Message ,it is need to define custom variable with any name and type as
* element,document,document_element By providing a expression ,It is possible to select a custom
* node for querying.The all the variable that have defined in the mediator will be available
* during the query process .Basic variable can use bind basic type.
* currently only support * string,int,byte,short,double,long,float and boolean * types.
* Custom Variable can use to bind XML documents ,SOAP payload and any basic type which create
* through the XPath expression .
*/
public class XQueryMediator extends AbstractMediator {
/* Properties that must set to the XQDataSource */
private final List<MediatorProperty> dataSourceProperties = new ArrayList<MediatorProperty>();
/* The key for lookup the xquery */
private String queryKey;
/* The source of the xquery */
private String querySource;
/*The target node*/
private final SourceXPathSupport target = new SourceXPathSupport();
/* The list of variables for binding to the DyanamicContext in order to available for querying */
private final List<MediatorVariable> variables = new ArrayList<MediatorVariable>();
/*Lock used to ensure thread-safe lookup of the object from the registry */
private final Object resourceLock = new Object();
/* Is it need to use DOMSource and DOMResult? */
private boolean useDOMSource = false;
/*The DataSource which use to create a connection to XML database */
private XQDataSource cachedXQDataSource = null;
/* connection with a specific XQuery engine.Connection will live as long as synapse live */
private XQConnection cachedConnection = null;
/* An expression that use for multiple executions.Expression will recreate if query has changed */
private XQPreparedExpression cachedPreparedExpression = null;
public XQueryMediator() {
}
/**
* Performs the query and attached the result to the target Node
*
* @param synCtx The current message
* @return true always
*/
public boolean mediate(MessageContext synCtx) {
try {
SynapseLog synLog = getLog(synCtx);
if (synLog.isTraceOrDebugEnabled()) {
synLog.traceOrDebug("Start : XQuery mediator");
if (synLog.isTraceTraceEnabled()) {
synLog.traceTrace("Message : " + synCtx.getEnvelope());
}
synLog.traceOrDebug("Performing XQuery using query resource with key : " +
queryKey);
}
// perform the xquery
performQuery(synCtx, synLog);
synLog.traceOrDebug("End : XQuery mediator");
return true;
} catch (Exception e) {
handleException("Unable to execute the query ", e);
}
return false;
}
/**
* Perform the quering and get the result and attached to the target node
*
* @param synCtx The current MessageContext
* @param synLog the Synapse log to use
*/
private void performQuery(MessageContext synCtx, SynapseLog synLog) {
boolean reLoad = false;
boolean needBind = false;
XQResultSequence resultSequence;
if (queryKey != null && !"".equals(queryKey)) {
Entry dp = synCtx.getConfiguration().getEntryDefinition(queryKey);
// if the queryKey refers to a dynamic resource
if (dp != null && dp.isDynamic()) {
if (!dp.isCached() || dp.isExpired()) {
reLoad = true;
}
}
}
try {
synchronized (resourceLock) {
//creating data source
if (cachedXQDataSource == null) {
// A factory for XQConnection objects
cachedXQDataSource = new SaxonXQDataSource();
//setting up the properties to the XQDataSource
if (dataSourceProperties != null && !dataSourceProperties.isEmpty()) {
synLog.traceOrDebug("Setting up properties to the XQDataSource");
for (MediatorProperty dataSourceProperty : dataSourceProperties) {
if (dataSourceProperty != null) {
cachedXQDataSource.setProperty(dataSourceProperty.getName(),
dataSourceProperty.getValue());
}
}
}
}
//creating connection
if (cachedConnection == null
|| (cachedConnection != null && cachedConnection.isClosed())) {
//get the Connection to XML DataBase
synLog.traceOrDebug("Creating a connection from the XQDataSource ");
cachedConnection = cachedXQDataSource.getConnection();
}
// prepare the expression to execute query
if (reLoad || cachedPreparedExpression == null
|| (cachedPreparedExpression != null
&& cachedPreparedExpression.isClosed())) {
if (querySource != null && !"".equals(querySource)) {
if (cachedPreparedExpression == null) {
if (synLog.isTraceOrDebugEnabled()) {
synLog.traceOrDebug("Using in-lined query source - " + querySource);
synLog.traceOrDebug("Prepare an expression for the query ");
}
//create an XQPreparedExpression using the query source
cachedPreparedExpression =
cachedConnection.prepareExpression(querySource);
// need binding because the expression just has recreated
needBind = true;
}
} else {
Object o = synCtx.getEntry(queryKey);
if (o == null) {
if (synLog.isTraceOrDebugEnabled()) {
synLog.traceOrDebug("Couldn't find the xquery source with a key "
+ queryKey);
}
return;
}
String sourceCode = null;
InputStream inputStream = null;
if (o instanceof OMElement) {
sourceCode = ((OMElement) (o)).getText();
} else if (o instanceof String) {
sourceCode = (String) o;
} else if (o instanceof OMText) {
DataHandler dataHandler = (DataHandler) ((OMText) o).getDataHandler();
if (dataHandler != null) {
try {
inputStream = dataHandler.getInputStream();
if (inputStream == null) {
if (synLog.isTraceOrDebugEnabled()) {
synLog.traceOrDebug("Couldn't get" +
" the stream from the xquery source with a key "
+ queryKey);
}
return;
}
} catch (IOException e) {
handleException("Error in reading content as a stream ");
}
}
}
if ((sourceCode == null || "".equals(sourceCode)) && inputStream == null) {
if (synLog.isTraceOrDebugEnabled()) {
synLog.traceOrDebug("Couldn't find the xquery source with a key "
+ queryKey);
}
return;
}
if (synLog.isTraceOrDebugEnabled()) {
synLog.traceOrDebug("Picked up the xquery source from the " +
"key " + queryKey);
synLog.traceOrDebug("Prepare an expression for the query ");
}
if (sourceCode != null) {
//create an XQPreparedExpression using the query source
cachedPreparedExpression =
cachedConnection.prepareExpression(sourceCode);
} else {
//create an XQPreparedExpression using the query source stream
cachedPreparedExpression =
cachedConnection.prepareExpression(inputStream);
}
// need binding because the expression just has recreated
needBind = true;
}
}
//Bind the external variables to the DynamicContext
if (variables != null && !variables.isEmpty()) {
synLog.traceOrDebug("Binding external variables to the DynamicContext");
for (MediatorVariable variable : variables) {
if (variable != null) {
boolean hasValueChanged = variable.evaluateValue(synCtx);
//if the value has changed or need binding because the expression has recreated
if (hasValueChanged || needBind) {
//Binds the external variable to the DynamicContext
bindVariable(cachedPreparedExpression, variable, synLog);
}
}
}
}
//executing the query
resultSequence = cachedPreparedExpression.executeQuery();
}
if (resultSequence == null) {
synLog.traceOrDebug("Result Sequence is null");
return;
}
//processing the result
while (resultSequence.next()) {
XQItem xqItem = resultSequence.getItem();
if (xqItem == null) {
return;
}
XQItemType itemType = xqItem.getItemType();
if (itemType == null) {
return;
}
int itemKind = itemType.getItemKind();
int baseType = itemType.getBaseType();
if (synLog.isTraceOrDebugEnabled()) {
synLog.traceOrDebug("The XQuery Result " + xqItem.getItemAsString());
}
//The target node that is going to modify
OMNode destination = target.selectOMNode(synCtx, synLog);
if (destination != null) {
if (synLog.isTraceOrDebugEnabled()) {
synLog.traceOrDebug("The target node " + destination);
}
//If the result is XML
if (XQItemType.XQITEMKIND_DOCUMENT_ELEMENT == itemKind ||
XQItemType.XQITEMKIND_ELEMENT == itemKind ||
XQItemType.XQITEMKIND_DOCUMENT == itemKind) {
StAXOMBuilder builder = new StAXOMBuilder(
XMLInputFactory.newInstance().createXMLStreamReader(
new StringReader(xqItem.getItemAsString())));
OMElement resultOM = builder.getDocumentElement();
if (resultOM != null) {
//replace the target node from the result
destination.insertSiblingAfter(resultOM);
destination.detach();
}
} else if (XQItemType.XQBASETYPE_INTEGER == baseType ||
XQItemType.XQBASETYPE_INT == baseType) {
//replace the text value of the target node by the result ,If the result is
// a basic type
((OMElement) destination).setText(String.valueOf(xqItem.getInt()));
} else if (XQItemType.XQBASETYPE_BOOLEAN == baseType) {
((OMElement) destination).setText(String.valueOf(xqItem.getBoolean()));
} else if (XQItemType.XQBASETYPE_DOUBLE == baseType) {
((OMElement) destination).setText(String.valueOf(xqItem.getDouble()));
} else if (XQItemType.XQBASETYPE_FLOAT == baseType) {
((OMElement) destination).setText(String.valueOf(xqItem.getFloat()));
} else if (XQItemType.XQBASETYPE_LONG == baseType) {
((OMElement) destination).setText(String.valueOf(xqItem.getLong()));
} else if (XQItemType.XQBASETYPE_SHORT == baseType) {
((OMElement) destination).setText(String.valueOf(xqItem.getShort()));
} else if (XQItemType.XQBASETYPE_BYTE == baseType) {
((OMElement) destination).setText(String.valueOf(xqItem.getByte()));
} else if (XQItemType.XQBASETYPE_STRING == baseType) {
((OMElement) destination).setText(
String.valueOf(xqItem.getItemAsString()));
}
}
break; // Only take the *first* value of the result sequence
}
resultSequence.close(); // closing the result sequence
} catch (XQException e) {
handleException("Error during the querying " + e.getMessage(), e);
} catch (XMLStreamException e) {
handleException("Error during retrieving the Doument Node as the result "
+ e.getMessage(), e);
}
}
/**
* Binding a variable to the Dynamic Context in order to available during doing the querying
*
* @param xqDynamicContext The Dynamic Context to which the variable will be binded
* @param variable The variable which contains the name and vaule for binding
* @param synLog the Synapse log to use
* @throws XQException throws if any error occurs when binding the variable
*/
private void bindVariable(XQDynamicContext xqDynamicContext, MediatorVariable variable,
SynapseLog synLog) throws XQException {
if (variable != null) {
QName name = variable.getName();
int type = variable.getType();
Object value = variable.getValue();
if (value != null && type != -1) {
if (synLog.isTraceOrDebugEnabled()) {
synLog.traceOrDebug("Binding a variable to the DynamicContext with a name : "
+ name + " and a value : " + value);
}
switch (type) {
//Binding the basic type As-Is and XML element as an InputSource
case (XQItemType.XQBASETYPE_BOOLEAN): {
boolean booleanValue = false;
if (value instanceof String) {
booleanValue = Boolean.parseBoolean((String) value);
} else if (value instanceof Boolean) {
booleanValue = (Boolean) value;
} else {
handleException("Incompatible type for the Boolean");
}
xqDynamicContext.bindBoolean(name, booleanValue, null);
break;
}
case (XQItemType.XQBASETYPE_INTEGER): {
int intValue = -1;
if (value instanceof String) {
try {
intValue = Integer.parseInt((String) value);
} catch (NumberFormatException e) {
handleException("Incompatible value '" + value + "' " +
"for the Integer", e);
}
} else if (value instanceof Integer) {
intValue = (Integer) value;
} else {
handleException("Incompatible type for the Integer");
}
if (intValue != -1) {
xqDynamicContext.bindInt(name, intValue, null);
}
break;
}
case (XQItemType.XQBASETYPE_INT): {
int intValue = -1;
if (value instanceof String) {
try {
intValue = Integer.parseInt((String) value);
} catch (NumberFormatException e) {
handleException("Incompatible value '" + value +
"' for the Int", e);
}
} else if (value instanceof Integer) {
intValue = (Integer) value;
} else {
handleException("Incompatible type for the Int");
}
if (intValue != -1) {
xqDynamicContext.bindInt(name, intValue, null);
}
break;
}
case (XQItemType.XQBASETYPE_LONG): {
long longValue = -1;
if (value instanceof String) {
try {
longValue = Long.parseLong((String) value);
} catch (NumberFormatException e) {
handleException("Incompatible value '" + value + "' " +
"for the long ", e);
}
} else if (value instanceof Long) {
longValue = (Long) value;
} else {
handleException("Incompatible type for the Long");
}
if (longValue != -1) {
xqDynamicContext.bindLong(name, longValue, null);
}
break;
}
case (XQItemType.XQBASETYPE_SHORT): {
short shortValue = -1;
if (value instanceof String) {
try {
shortValue = Short.parseShort((String) value);
} catch (NumberFormatException e) {
handleException("Incompatible value '" + value + "' " +
"for the short ", e);
}
} else if (value instanceof Short) {
shortValue = (Short) value;
} else {
handleException("Incompatible type for the Short");
}
if (shortValue != -1) {
xqDynamicContext.bindShort(name, shortValue, null);
}
break;
}
case (XQItemType.XQBASETYPE_DOUBLE): {
double doubleValue = -1;
if (value instanceof String) {
try {
doubleValue = Double.parseDouble((String) value);
} catch (NumberFormatException e) {
handleException("Incompatible value '" + value + "' " +
"for the double ", e);
}
} else if (value instanceof Double) {
doubleValue = (Double) value;
} else {
handleException("Incompatible type for the Double");
}
if (doubleValue != -1) {
xqDynamicContext.bindDouble(name, doubleValue, null);
}
break;
}
case (XQItemType.XQBASETYPE_FLOAT): {
float floatValue = -1;
if (value instanceof String) {
try {
floatValue = Float.parseFloat((String) value);
} catch (NumberFormatException e) {
handleException("Incompatible value '" + value + "' " +
"for the float ", e);
}
} else if (value instanceof Float) {
floatValue = (Float) value;
} else {
handleException("Incompatible type for the Float");
}
if (floatValue != -1) {
xqDynamicContext.bindFloat(name, floatValue, null);
}
break;
}
case (XQItemType.XQBASETYPE_BYTE): {
byte byteValue = -1;
if (value instanceof String) {
try {
byteValue = Byte.parseByte((String) value);
} catch (NumberFormatException e) {
handleException("Incompatible value '" + value + "' " +
"for the byte ", e);
}
} else if (value instanceof Byte) {
byteValue = (Byte) value;
} else {
handleException("Incompatible type for the Byte");
}
if (byteValue != -1) {
xqDynamicContext.bindByte(name, byteValue, null);
}
break;
}
case (XQItemType.XQBASETYPE_STRING): {
if (value instanceof String) {
xqDynamicContext.bindObject(name, value, null);
} else {
handleException("Incompatible type for the String");
}
break;
}
case (XQItemType.XQITEMKIND_DOCUMENT): {
bindOMNode(name, value, xqDynamicContext);
break;
}
case (XQItemType.XQITEMKIND_ELEMENT): {
bindOMNode(name, value, xqDynamicContext);
break;
}
case (XQItemType.XQITEMKIND_DOCUMENT_ELEMENT): {
bindOMNode(name, value, xqDynamicContext);
break;
}
default: {
handleException("Unsupported type for the binding type" + type +
" in the variable name " + name);
break;
}
}
}
}
}
private void bindOMNode(QName name, Object value,
XQDynamicContext xqDynamicContext) throws XQException {
OMElement variableValue = null;
if (value instanceof String) {
variableValue = SynapseConfigUtils.stringToOM((String) value);
} else if (value instanceof OMElement) {
variableValue = (OMElement) value;
}
if (variableValue != null) {
if (useDOMSource) {
xqDynamicContext.
bindObject(name,
new DOMSource(((Element) ElementHelper.
importOMElement(variableValue,
DOOMAbstractFactory.getOMFactory())).
getOwnerDocument()), null);
} else {
xqDynamicContext.bindDocument(name,
new InputSource(SynapseConfigUtils.getInputStream(
variableValue)));
}
}
}
private void handleException(String msg, Exception e) {
log.error(msg, e);
throw new SynapseException(msg, e);
}
private void handleException(String msg) {
log.error(msg);
throw new SynapseException(msg);
}
public String getQueryKey() {
return queryKey;
}
public void setQueryKey(String queryKey) {
this.queryKey = queryKey;
}
public String getQuerySource() {
return querySource;
}
public void setQuerySource(String querySource) {
this.querySource = querySource;
}
public void addAllVariables(List<MediatorVariable> list) {
this.variables.addAll(list);
}
public void addVariable(MediatorVariable variable) {
this.variables.add(variable);
}
public List<MediatorProperty> getDataSourceProperties() {
return dataSourceProperties;
}
public List<MediatorVariable> getVariables() {
return variables;
}
public SynapseXPath getTarget() {
return target.getXPath();
}
public void setTarget(SynapseXPath source) {
this.target.setXPath(source);
}
public void addAllDataSourceProperties(List<MediatorProperty> list) {
this.dataSourceProperties.addAll(list);
}
public boolean isUseDOMSource() {
return useDOMSource;
}
public void setUseDOMSource(boolean useDOMSource) {
this.useDOMSource = useDOMSource;
}
}