Skip to content

Commit

Permalink
Merge pull request #9 from CrossBreezeNL/feature/SaxonForModelPreproc…
Browse files Browse the repository at this point in the history 
…essing

Feature/saxon for model preprocessing
  • Loading branch information
@harmen-xb
harmen-xb authored Oct 25, 2024
2 parents c44c44d + 575e8ff commit bbdeca9
Show file tree
Hide file tree
Showing 4 changed files with 243 additions and 174 deletions.
291 changes: 123 additions & 168 deletions XGenerate/src/main/java/com/xbreeze/xgenerate/model/ModelPreprocessor.java
View file
Original file line number Diff line number Diff line change
Expand Up @@ -24,242 +24,197 @@
*******************************************************************************/
package com.xbreeze.xgenerate.model;

import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.logging.Logger;
import java.util.stream.Collectors;

import com.xbreeze.xgenerate.config.NamespaceConfig;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.xpath.XPathConstants;
import javax.xml.xpath.XPathExpressionException;

import org.w3c.dom.Attr;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.xml.sax.SAXException;

import com.xbreeze.xgenerate.config.model.ModelAttributeInjection;
import com.xbreeze.xgenerate.config.model.ModelAttributeInjectionValueMapping;
import com.xbreeze.xgenerate.config.model.ModelConfig;
import com.xbreeze.xgenerate.config.model.ModelNodeRemoval;
import com.xbreeze.xgenerate.generator.GeneratorException;
import com.xbreeze.xgenerate.utils.XMLUtils;
import com.ximpleware.AutoPilot;
import com.ximpleware.ModifyException;
import com.ximpleware.NavException;
import com.ximpleware.ParseException;
import com.ximpleware.TranscodeException;
import com.ximpleware.VTDNav;
import com.ximpleware.XMLModifier;
import com.ximpleware.XPathEvalException;
import com.ximpleware.XPathParseException;
import com.xbreeze.xgenerate.utils.SaxonXMLUtils;
import com.xbreeze.xgenerate.utils.XmlException;

import net.sf.saxon.xpath.XPathExpressionImpl;


/**
* The model preprocessor.
*
* @author Harmen
*/
public class ModelPreprocessor {
private static final Logger logger = Logger.getLogger(ModelPreprocessor.class.getName());

/**
* Pre-process the model.
*
* @param model
* @param modelConfig
* @throws ModelPreprocessorException
* @throws ModelPreprocessorException
*/
public static void preprocessModel(Model model, ModelConfig modelConfig) throws ModelPreprocessorException {
logger.info("Starting model preprocessing");

/// Store the pre-processed model.
String preprocessedModel = model.getModelFileContent();
// Load the preprocessed model into memory
DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
DocumentBuilder builder;

try {
builder = factory.newDocumentBuilder();
} catch (ParserConfigurationException exc) {
throw new ModelPreprocessorException(
String.format("Error while reading model XML file: %s", exc.getMessage()));
}
Document doc;
SaxonXMLUtils xmlHelper = new SaxonXMLUtils();
xmlHelper.setNamespaces(modelConfig.getNamespaces());

try {
doc = builder.parse(new ByteArrayInputStream(model.getModelFileContent().getBytes()));
} catch(SAXException | IOException exc) {
throw new ModelPreprocessorException("Error while reading model XML file", exc.getCause());
}


// ModelAttributeInjections
// First do attribute injection, in case attributes are used as source that are removed in the next step
if (modelConfig != null && modelConfig.getModelAttributeInjections() != null && modelConfig.getModelAttributeInjections().size() > 0) {
preprocessedModel = performModelAttributeInjections(preprocessedModel, modelConfig.getModelAttributeInjections(), modelConfig.getNamespaces());
// First do attribute injection, in case attributes are used as source that are
// removed in the next step
if (modelConfig != null && modelConfig.getModelAttributeInjections() != null
&& modelConfig.getModelAttributeInjections().size() > 0) {
doc = performModelAttributeInjections(doc, xmlHelper,
modelConfig.getModelAttributeInjections());
}


// ModelNodeRemovals
if (modelConfig != null && modelConfig.getModelNodeRemovals() != null && modelConfig.getModelNodeRemovals().size() > 0) {
preprocessedModel = performModelNodeRemovals(preprocessedModel, modelConfig.getModelNodeRemovals(), modelConfig.getNamespaces());
if (modelConfig != null && modelConfig.getModelNodeRemovals() != null
&& modelConfig.getModelNodeRemovals().size() > 0) {
doc = performModelNodeRemovals(doc, xmlHelper, modelConfig.getModelNodeRemovals());
}

// Store the pre-processed model in the Model object.
model.setPreprocessedModel(preprocessedModel);

logger.info("End model preprocessing");
}

private static String performModelNodeRemovals(String preprocessedModel, ArrayList<ModelNodeRemoval> modelModelNodeRemovals, ArrayList<NamespaceConfig> namespaces) throws ModelPreprocessorException {
logger.fine("Performing model node removals.");

// Execute the model XPath on the Document.
VTDNav nv;
//Transform the preprocessed document to string and store it in the model object.
String preprocessedModel;
try {
nv = XMLUtils.getVTDNav(preprocessedModel, (namespaces != null && namespaces.size() > 0));
} catch (GeneratorException e) {
throw new ModelPreprocessorException(String.format("Error while reading model before pre-processing: %s", e.getMessage()), e);
preprocessedModel = SaxonXMLUtils.XmlDocumentToString(doc);
} catch (XmlException e) {
throw new ModelPreprocessorException("Error transforming preprocessed model to string", e.getCause());
}

// Create a modifier to modify the model document.
XMLModifier xm;
try {
xm = new XMLModifier(nv);
} catch (ModifyException e) {
throw new ModelPreprocessorException(e);
}

// Store the pre-processed model as string in the Model object.
model.setPreprocessedModel(preprocessedModel);

logger.info("End model preprocessing");
}

private static Document performModelNodeRemovals(Document modelDoc, SaxonXMLUtils xmlHelper,
ArrayList<ModelNodeRemoval> modelModelNodeRemovals)
throws ModelPreprocessorException {

logger.fine("Performing model node removals.");
// Loop through the model node removals and process them.
for (ModelNodeRemoval mnr : modelModelNodeRemovals) {
// Create an AutoPilot for querying the document.
AutoPilot ap = new AutoPilot(nv);

// If namespaces are defined, register then on the auto pilot.
if (namespaces != null && namespaces.size() > 0) {
// Register the declared namespaces.
for (NamespaceConfig namespace : namespaces) {
ap.declareXPathNameSpace(namespace.getPrefix(), namespace.getNamespace());
}
}

try {
// Set the XPath expression from the config.
ap.selectXPath(mnr.getModelXPath());

// Execute the XPath expression and loop through the results.
while ((ap.evalXPath()) != -1) {
// Remove the node.
xm.remove();
}

// Output and re-parse the document for the next injection.
// This is necessary, otherwise exceptions will be thrown when injecting attributes for the same element.
nv = xm.outputAndReparse();
// Reset and bind the modifier to the new VTDNav object.
xm.reset();
xm.bind(nv);

} catch (XPathParseException | XPathEvalException | NavException | ModifyException | ParseException | TranscodeException | IOException e) {
throw new ModelPreprocessorException(String.format("Error while processing model node removal for XPath ´%s´: %s", mnr.getModelXPath(), XMLUtils.getAutopilotExceptionMessage(mnr.getModelXPath(), e)));
XPathExpressionImpl expr = xmlHelper.getXPathExpression(mnr.getModelXPath());
NodeList result = (NodeList) expr.evaluate(modelDoc, XPathConstants.NODESET);
for (int i = 0; i < result.getLength(); i++) {
Node node = result.item(i);
if (node.getNodeType() == Node.ELEMENT_NODE) {
node.getParentNode().removeChild(node);
} else if (node.getNodeType() == Node.ATTRIBUTE_NODE) {
((Attr)node).getOwnerElement().removeAttributeNode((Attr)node);
}
}
} catch (XPathExpressionException e) {
throw new ModelPreprocessorException(String.format("Error processing XPath expression for node removal %s", mnr.getModelXPath()), e.getCause());
}
}

// Return the modified XML document.
try {
return XMLUtils.getResultingXml(xm);
} catch (GeneratorException e) {
throw new ModelPreprocessorException(e);
}
return modelDoc;
}

private static String performModelAttributeInjections(String preprocessedModel, ArrayList<ModelAttributeInjection> modelAttributeInjections, ArrayList<NamespaceConfig> namespaces) throws ModelPreprocessorException {

private static Document performModelAttributeInjections(Document modelDoc, SaxonXMLUtils xmlHelper,
ArrayList<ModelAttributeInjection> modelAttributeInjections)
throws ModelPreprocessorException {
logger.fine("Performing model attribute injections.");

// Execute the model XPath on the Document.
VTDNav nv;
try {
// Set the VTD nav to namespace aware if the namespaces are defined.
nv = XMLUtils.getVTDNav(preprocessedModel, (namespaces != null && namespaces.size() > 0));
} catch (GeneratorException e) {
throw new ModelPreprocessorException(String.format("Error while reading model before performing model attribute injections: %s", e.getMessage()), e);
}

// Create a modifier to modify the model document.
XMLModifier xm;
try {
xm = new XMLModifier(nv);
} catch (ModifyException e) {
throw new ModelPreprocessorException(e);
}


// Loop through the model attribute injections and process them.
for (ModelAttributeInjection mai : modelAttributeInjections) {
// Create an AutoPilot for querying the document.
AutoPilot ap = new AutoPilot(nv);

// If namespaces are defined, register then on the auto pilot.
if (namespaces != null && namespaces.size() > 0) {
// Register the declared namespaces.
for (NamespaceConfig namespace : namespaces) {
ap.declareXPathNameSpace(namespace.getPrefix(), namespace.getNamespace());
}
}

try {
XPathExpressionImpl expr = xmlHelper.getXPathExpression(mai.getModelXPath());

// Set the XPath expression from the config.
ap.selectXPath(mai.getModelXPath());

// Execute the XPath expression and loop through the results.
while ((ap.evalXPath()) != -1) {

String targetValue = null;

// Set the attribute value, either from XPath or constant value
if (mai.getTargetXPath() != null) {
// Execute the XPath on the current node.
NodeList result = (NodeList) expr.evaluate(modelDoc, XPathConstants.NODESET);
for (int i = 0; i < result.getLength(); i++) {
Node node = result.item(i);
String targetValue = null;
//If a target xpath is set, evaluate it to get a value
if (mai.getTargetXPath() !=null) {
try {
AutoPilot ap_targetValue = new AutoPilot(nv);
ap_targetValue.selectXPath(mai.getTargetXPath());
targetValue = ap_targetValue.evalXPathToString();
logger.info(String.format("Target XPath defined for attribute injection, value: ´%s´ => ´%s´", mai.getTargetXPath(), targetValue));
}
catch (XPathParseException e) {
throw new ModelPreprocessorException(String.format("Error while processing model attribute injection for target XPath ´%s´: %s", mai.getTargetXPath(), XMLUtils.getAutopilotExceptionMessage(mai.getTargetXPath(), e)));
XPathExpressionImpl targetExpression = xmlHelper.getXPathExpression(mai.getTargetXPath());
targetValue = (String)targetExpression.evaluate(node, XPathConstants.STRING);
} catch (XPathExpressionException e) {
throw new ModelPreprocessorException(String.format("Error while processing model attribute injection for target XPath ´%s´", mai.getTargetXPath()), e.getCause());
}
}

// When the target value is set, write the value.
else if (mai.getTargetValue() != null) {
} else if (mai.getTargetValue() != null) {
targetValue = mai.getTargetValue();
}

// When the value mappings are set, process them.
else if (mai.getValueMappings() != null) {
} else if (mai.getValueMappings() != null ) {
//Get the input node value to use for finding the mapped output value
try {
AutoPilot ap_targetValue = new AutoPilot(nv);
// Get the value of the input node.
ap_targetValue.selectXPath(mai.getValueMappings().getInputNode());
String inputNodeValue = ap_targetValue.evalXPathToString();
// Using the input node value, find the output value from the value mapping.
List<ModelAttributeInjectionValueMapping> foundValueMappings = mai.getValueMappings().getModelAttributeInjectionValueMappings().stream().filter(vm -> vm.getInputValue().equals(inputNodeValue)).collect(Collectors.toList());
XPathExpressionImpl valueMappingExpression = xmlHelper.getXPathExpression(mai.getValueMappings().getInputNode());
String inputNodeValue = (String)valueMappingExpression.evaluate(node, XPathConstants.STRING);
List<ModelAttributeInjectionValueMapping> foundValueMappings = mai.getValueMappings()
.getModelAttributeInjectionValueMappings().stream()
.filter(vm -> vm.getInputValue().equals(inputNodeValue))
.collect(Collectors.toList());
// There should only be 1 found value mapping.
if (foundValueMappings.size() == 1) {
targetValue = foundValueMappings.get(0).getOutputValue();
logger.info(String.format("Value mappings defined for attribute injection, input node value: ´%s´, target value: ´%s´", inputNodeValue, targetValue));
logger.info(String.format(
"Value mappings defined for attribute injection, input node value: ´%s´, target value: ´%s´",
inputNodeValue, targetValue));
}
// If multiple value mappings are found, throw an exception.
else if (foundValueMappings.size() > 1) {
throw new ModelPreprocessorException(String.format("%d value mappings found for input node value ´%s´, expected exactly 1!", foundValueMappings.size(), inputNodeValue));
throw new ModelPreprocessorException(String.format(
"%d value mappings found for input node value ´%s´, expected exactly 1!",
foundValueMappings.size(), inputNodeValue));
}
// If no value mappings are found, print a warning.
else {
logger.warning(String.format("%d value mappings found for input node value ´%s´.", foundValueMappings.size(), inputNodeValue));
logger.warning(String.format("%d value mappings found for input node value ´%s´.",
foundValueMappings.size(), inputNodeValue));
}
}
catch (XPathParseException e) {
throw new ModelPreprocessorException(String.format("Error while processing model attribute injection for target XPath ´%s´: %s", mai.getTargetXPath(), XMLUtils.getAutopilotExceptionMessage(mai.getTargetXPath(), e)));
} catch (XPathExpressionException e) {
throw new ModelPreprocessorException(String.format("Error evaluating XPath expression for value mapping %s", mai.getValueMappings().getInputNode()), e.getCause());
}
}

// Append the attribute (if it is not null, this can happen if a value mapping returns no value).
if (targetValue != null)
XMLUtils.appendAttribute(nv, xm, mai.getTargetAttribute(), targetValue);
}

// Output and re-parse the document for the next injection.
// This is necessary, otherwise exceptions will be thrown when injecting attributes for the same element.
nv = xm.outputAndReparse();
// Reset and bind the modifier to the new VTDNav object.
xm.reset();
xm.bind(nv);

} catch (XPathParseException | XPathEvalException | NavException | ModifyException | ParseException | TranscodeException | IOException | GeneratorException e) {
// Throw a new exception.
throw new ModelPreprocessorException(String.format("Error while processing model attribute injection for model XPath ´%s´: %s", mai.getModelXPath(), XMLUtils.getAutopilotExceptionMessage(mai.getModelXPath(), e)));

if (targetValue != null && mai.getTargetAttribute() != null) {
((Element)node).setAttribute(mai.getTargetAttribute(), targetValue);
}
}
} catch (XPathExpressionException e) {
throw new ModelPreprocessorException(String.format("Error while processing model attribute injection for model XPath ´%s´", mai.getModelXPath()), e.getCause());
}
}

// Return the modified XML document.
try {
return XMLUtils.getResultingXml(xm);
} catch (GeneratorException e) {
throw new ModelPreprocessorException(e);
}
return modelDoc;
}
}
}
13 changes: 13 additions & 0 deletions XGenerate/src/main/java/com/xbreeze/xgenerate/model/ModelPreprocessorException.java
View file
Original file line number Diff line number Diff line change
Expand Up @@ -55,4 +55,17 @@ public ModelPreprocessorException(Throwable throwable) {
public ModelPreprocessorException(String message, Throwable throwable) {
super(message, throwable);
}

/**
* We override the localized message so we can construct the message ourselves, without listing the cause class names.
*/
@Override
public String getLocalizedMessage() {
if (this.getCause() != null) {
return String.format("%s: %s", this.getMessage(), this.getCause().getMessage());
} else {
return this.getMessage();
}
}

}
Loading

0 comments on commit bbdeca9

Please sign in to comment.