README.md

Example using CxxPath API

• Author: Pedric Kng
• Updated: 23 Oct 2018

The purpose of this project is to share XML query via CxAudit using cxXPath APIs.

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cxXPath

cxXPath is available since 8.6.0 and is a wrapper of .NET’s XPath C# API. Note that malformed XML is not supported i.e., missing xml header.

Examples

• Retrieve 'book' nodes in books.xml that contains author named "Corets, Eva"

foreach (CxXmlDoc doc in cxXPath.GetXmlFiles("books.xml", true)) {
  //declaration of a navigator for <book> node
  string xPath = @"/catalog/book[author = 'Corets, Eva']";

  XPathNavigator navigator = doc.CreateNavigator();  
  XPathNodeIterator nodeIterator = navigator.Select(xPath);

  foreach(XPathNavigator bookNode in nodeIterator) {
    result.Add(cxXPath.CreateXmlNode(bookNode, doc, 8, true));
  }
}

• Check that encryption is enforced in session 'cookie-store' as declared via 'session-encrypters' is in webx.xml

try {

	// Path declaration for <session-stores> node
	string xPathStore = @"/beans:beans/services:request-contexts/" +
		"request-contexts:session/stores/session-stores:cookie-store" +
		"[count(.//session-encrypters:aes-encrypter)=0]";

	foreach (CxXmlDoc doc in cxXPath.GetXmlFiles(@"webx.xml", true)) {

		// XPath Navigator
		XPathNavigator navigator = doc.CreateNavigator();  

		// Register namespace
		XmlNamespaceManager manager = new XmlNamespaceManager(navigator.NameTable);  
		manager.AddNamespace("beans", "http://www.springframework.org/schema/beans");  
		manager.AddNamespace("services", "http://www.alibaba.com/schema/services");
		manager.AddNamespace("request-contexts", "http://www.alibaba.com/schema/services/request-contexts");
		manager.AddNamespace("session-stores", "http://www.alibaba.com/schema/services/request-contexts/session/stores");
		manager.AddNamespace("session-encoders", "http://www.alibaba.com/schema/services/request-contexts/session/encoders");
		manager.AddNamespace("session-encrypters", "http://www.alibaba.com/schema/services/request-contexts/session/encrypters");

		// Declaration of a navigator for <session-stores> node
		XPathExpression storeQuery = navigator.Compile(xPathStore);
		storeQuery.SetContext(manager);  
		XPathNodeIterator storeIterator = navigator.Select(storeQuery);

		foreach(XPathNavigator storeNode in storeIterator) {
			result.Add(cxXPath.CreateXmlNode(storeNode, doc, 2, true));
		}
	}

}catch(Exception e){
	cxLog.WriteDebugMessage(e.Message);
}

• To resolve pom.xml which uses namespace with xPath , add the 'ns' namespace to the XmlNamespaceManager. Example shows returning result for 'junit' dependency discovered with version higher than 3.8

// Path declaration to find 'junit' dependency version
string xPathStore = "/ns:project/ns:dependencies/ns:dependency[ns:artifactId='junit']//ns:version";
foreach (CxXmlDoc doc in cxXPath.GetXmlFiles(@"pom.xml", false)) {

  // XPath Navigator
  XPathNavigator navigator = doc.CreateNavigator();  

  // Register namespace
  XmlNamespaceManager manager = new XmlNamespaceManager(navigator.NameTable);  
  manager.AddNamespace("ns", @"http://maven.apache.org/POM/4.0.0");  

  // Declaration of a navigator for <version> node
  XPathExpression storeQuery = navigator.Compile(xPathStore);
  storeQuery.SetContext(manager);  
  XPathNodeIterator storeIterator = navigator.Select(storeQuery);

  foreach(XPathNavigator storeNode in storeIterator) {

    char[] splitTokens = new char[] {'.', ','};
    String[] strAsplit = storeNode.Value.Split(splitTokens, StringSplitOptions.RemoveEmptyEntries);
    int[] versionA = new int[3];
    for (int i = 0; i < 3; i++)
    {
      versionA[i] = Convert.ToInt32(strAsplit[i]);
    }

    if(versionA[0] < 4 ){
      if(versionA[1] < 9)
        result.Add(cxXPath.CreateXmlNode(storeNode, doc, 2, true));
    }
  }
}

References

How to navigate XML with the XPathNavigator class by using Visual C# [1]
XPath Examples [2]
CxAudit Guide [3]