/*
* 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;
import org.apache.axiom.om.*;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.synapse.MessageContext;
import org.apache.synapse.SynapseException;
import org.apache.synapse.config.xml.SynapsePath;
import org.apache.synapse.util.xpath.SynapseJsonPath;
import org.apache.synapse.util.xpath.SynapseXPath;
import org.jaxen.JaxenException;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
/**
* Represents a Value
* Handling both static and dynamic(Xpath) keys.
* User can give Xpath expression as a key and derive
* real key based on message context
*/
public class Value {
private static final Log log = LogFactory.getLog(Value.class);
/**
* Name of the value attribute
*/
private String name = null;
/**
* The static key value
*/
private String keyValue = null;
/**
* the dynamic key
*/
private SynapsePath expression = null;
private List<OMNamespace> namespaceList = new ArrayList<OMNamespace>();
/**
* Create a key instance using a static key
*
* @param staticKey static key
*/
public Value(String staticKey) {
this.keyValue = staticKey;
}
/**
* Create a key instance using a dynamic key (Xpath or JsonPath Expression)
*
* @param expression SynapsePath for dynamic key
*/
public Value(SynapsePath expression) {
this.expression = expression;
}
/**
* Retrieving static key
*
* @return static key
*/
public String getKeyValue() {
return keyValue;
}
/**
* Retrieving dynamic key
*
* @return SynapsePath
*/
public SynapsePath getExpression() {
if (expression == null && keyValue != null && hasExprTypeKey()) {
try {
String expressionString = keyValue.substring(1, keyValue.length() - 1);
if (expressionString.startsWith("json-eval(")) {
// Remove "json-eval" and extract the json expression
SynapseJsonPath expressionTypeKey =
new SynapseJsonPath(expressionString.substring(10, expressionString.length() - 1));
expression = expressionTypeKey;
} else {
SynapseXPath expressionTypeKey = new SynapseXPath(expressionString);
for (OMNamespace aNamespaceList : namespaceList) {
expressionTypeKey.addNamespace(aNamespaceList);
}
expression = expressionTypeKey;
}
} catch (JaxenException e) {
expression = null;
handleException("Can not evaluate escaped expression..");
}
}
return expression;
}
/**
* Evaluating key based on message context
* used when key is a xpath expression
*
* @param synCtx message context
* @return string value of evaluated key
*/
public String evaluateValue(MessageContext synCtx) {
if (keyValue != null) {
//if static kry: return static key
return keyValue;
} else if (expression != null) {
//if dynamic key return evaluated value
return expression.stringValueOf(synCtx);
} else {
handleException("Can not evaluate the key: " +
"key should be static or dynamic key");
return null;
}
}
public Object evaluateObjectValue(MessageContext synCtx) {
if (keyValue != null) {
return keyValue;
} else if (expression != null) {
return getObjectValue(synCtx);
} else {
handleException("Unable to resolve the value: " + toString());
return null;
}
}
private Object getObjectValue(MessageContext synCtx) {
try {
Object result = expression.selectSingleNode(synCtx);
if (result instanceof OMText) {
return ((OMText) result).getText();
} else if (result instanceof OMElement) {
return ((OMElement) result).getText();
} else if (result instanceof OMDocument) {
return ((OMDocument) result).getOMDocumentElement().toString();
} else if (result instanceof OMAttribute) {
return ((OMAttribute) result).getAttributeValue();
} else {
return result;
}
} catch (JaxenException e) {
handleException("Failed to evaluate the XPath expression: " + expression, e);
}
return null;
}
/**
* Get the name of the value attribute
*
* @return name of the value attribute
*/
public String getName() {
return name;
}
/**
* Handle exceptions
*
* @param msg error message
*/
private void handleException(String msg) {
log.error(msg);
throw new SynapseException(msg);
}
private void handleException(String msg, Exception e) {
log.error(msg, e);
throw new SynapseException(msg, e);
}
/**
* checks whether key returned by #getKeyValue() is a string of an expression type.
* @return if true if this is an expression
*/
public boolean hasExprTypeKey() {
return keyValue != null && keyValue.startsWith("{") && keyValue.endsWith("}");
}
public boolean hasPropertyEvaluateExpr(){
return keyValue != null && keyValue.contains("get-property");
}
public Object evalutePropertyExpression(MessageContext synCtx) {
//this.keyValue = null;
//String evaluatedProperty = this.evaluateValue(synCtx);
SynapseXPath _expression = null;
try {
_expression = new SynapseXPath(this.keyValue.substring(1, keyValue.length() - 1));
for (OMNamespace aNamespaceList : namespaceList) {
_expression.addNamespace(aNamespaceList);
}
String result =_expression.stringValueOf(synCtx);
SynapseXPath expression = new SynapseXPath(result);
for (OMNamespace aNamespaceList : namespaceList) {
expression.addNamespace(aNamespaceList);
}
return expression;
} catch (Exception e) {
handleException("Can not evaluate escaped expression..");
}
return this.expression;
}
public void setNamespaces(OMElement elem){
Iterator namespaces = elem.getAllDeclaredNamespaces();
while (namespaces.hasNext()){
OMNamespace ns = (OMNamespace) namespaces.next();
namespaceList.add(ns);
}
}
@Override
public String toString() {
return "Value {" +
"name ='" + name + '\'' +
(keyValue != null ? ", keyValue ='" + keyValue + '\'' : "") +
(expression != null ? ", expression =" + expression : "") +
'}';
}
}