/// <summary>
/// Return the xPath corresponding to the given property. The PropertyName String
/// may be simple, nested, indexed or mapped.
/// </summary>
/// <param name="propertyName">is the event property name</param>
/// <param name="namespace">is the default namespace</param>
/// <param name="schemaModel">is the schema model</param>
/// <param name="xPathContext">is the xpath factory instance to use</param>
/// <param name="rootElementName">is the name of the root element</param>
/// <param name="eventAdapterService">for type lookup and creation</param>
/// <param name="xmlEventType">the resolving type</param>
/// <param name="isAllowFragment">whether fragmenting is allowed</param>
/// <param name="defaultNamespace">default namespace</param>
/// <returns>
/// xpath expression
/// </returns>
/// <throws>EPException is there are XPath errors</throws>
public static EventPropertyGetter GetXPathResolution(String propertyName,
XPathNamespaceContext xPathContext,
String rootElementName,
String @namespace,
SchemaModel schemaModel,
EventAdapterService eventAdapterService,
BaseXMLEventType xmlEventType,
bool isAllowFragment,
String defaultNamespace)
{
if (Log.IsDebugEnabled)
{
Log.Debug("Determining XPath expression for property '" + propertyName + "'");
}
var ctx = new XPathNamespaceContext();
var namespaces = schemaModel.Namespaces;
string defaultNamespacePrefix = null;
for (int i = 0; i < namespaces.Count; i++)
{
var namespacePrefix = "n" + i;
ctx.AddNamespace(namespacePrefix, namespaces[i]);
if ((defaultNamespace != null) && (defaultNamespace == namespaces[i]))
{
defaultNamespacePrefix = namespacePrefix;
}
}
Property property = PropertyParser.ParseAndWalk(propertyName);
var isDynamic = property.IsDynamic;
var rootComplexElement = SchemaUtil.FindRootElement(schemaModel, @namespace, rootElementName);
string prefix = ctx.LookupPrefix(rootComplexElement.Namespace);
if (prefix == null)
{
prefix = "";
}
else
{
prefix += ':';
}
var xPathBuf = new StringBuilder();
xPathBuf.Append('/');
xPathBuf.Append(prefix);
if (rootElementName.StartsWith("//"))
{
xPathBuf.Append(rootElementName.Substring(2));
}
else
{
xPathBuf.Append(rootElementName);
}
var parentComplexElement = rootComplexElement;
Pair <String, XPathResultType> pair = null;
if (!(property is NestedProperty))
{
pair = MakeProperty(rootComplexElement, property, ctx, true, isDynamic, defaultNamespacePrefix);
if (pair == null)
{
throw new PropertyAccessException("Failed to locate property '" + propertyName + "' in schema");
}
xPathBuf.Append(pair.First);
}
else
{
NestedProperty nestedProperty = (NestedProperty)property;
int indexLast = nestedProperty.Properties.Count - 1;
for (int i = 0; i < indexLast + 1; i++)
{
var isLast = i == indexLast;
var propertyNested = nestedProperty.Properties[i];
pair = MakeProperty(parentComplexElement, propertyNested, ctx, isLast, isDynamic, defaultNamespacePrefix);
if (pair == null)
{
throw new PropertyAccessException("Failed to locate property '" + propertyName + "' nested property part '" + property.PropertyNameAtomic + "' in schema");
}
var text = propertyNested.PropertyNameAtomic;
var obj = SchemaUtil.FindPropertyMapping(parentComplexElement, text);
if (obj is SchemaElementComplex)
{
parentComplexElement = (SchemaElementComplex)obj;
}
xPathBuf.Append(pair.First);
}
}
var xPath = xPathBuf.ToString();
if ((ExecutionPathDebugLog.IsEnabled) && (Log.IsDebugEnabled))
{
Log.Debug(".parse XPath for property '" + propertyName + "' is expression=" + xPath);
}
// Compile assembled XPath expression
if (Log.IsDebugEnabled)
{
Log.Debug("Compiling XPath expression '" + xPath + "' for property '" + propertyName + "' using namespace context :" + ctx);
}
XPathExpression expr;
try
{
expr = XPathExpression.Compile(xPath, ctx);
}
catch (XPathException e) {
String detail = "Error constructing XPath expression from property expression '" + propertyName + "' expression '" + xPath + "'";
if (e.Message != null)
{
throw new EPException(detail + " :" + e.Message, e);
}
throw new EPException(detail, e);
}
// get type
var item = property.GetPropertyTypeSchema(rootComplexElement, eventAdapterService);
if ((item == null) && (!isDynamic))
{
return(null);
}
var resultType = isDynamic ? typeof(XmlNode) : SchemaUtil.ToReturnType(item);
FragmentFactory fragmentFactory = null;
if (isAllowFragment)
{
fragmentFactory = new FragmentFactoryDOMGetter(eventAdapterService, xmlEventType, propertyName);
}
return(new XPathPropertyGetter(propertyName, xPath, expr, pair.Second, resultType, fragmentFactory));
}
/// <summary>
/// Ctor.
/// </summary>
/// <param name="eventAdapterService">for event type lookup</param>
/// <param name="xmlEventType">the originating type</param>
/// <param name="propertyExpression">property expression</param>
public FragmentFactoryDOMGetter(EventAdapterService eventAdapterService, BaseXMLEventType xmlEventType, String propertyExpression)
{
_eventAdapterService = eventAdapterService;
_xmlEventType = xmlEventType;
_propertyExpression = propertyExpression;
}