//
// the core policy reading logic
// each step returns a list of lists -- an "and of ors":
// each inner list is a policy alternative: it contains the set of assertions that comprise the alternative
// the outer list represents the choice between alternatives
//
private IEnumerable <IEnumerable <XmlElement> > ReadNode(XmlNode node, XmlElement contextAssertion, YieldLimiter yieldLimiter)
{
if (_nodesRead >= _metadataImporter.Quotas.MaxPolicyNodes)
{
if (_nodesRead == _metadataImporter.Quotas.MaxPolicyNodes)
{
// add wirning once
string warningMsg = string.Format(SRServiceModel.ExceededMaxPolicyComplexity, node.Name, PolicyHelper.GetFragmentIdentifier((XmlElement)node));
_metadataImporter.PolicyWarningOccured.Invoke(contextAssertion, warningMsg);
_nodesRead++;
}
return(s_emptyEmpty);
}
_nodesRead++;
IEnumerable <IEnumerable <XmlElement> > nodes = s_emptyEmpty;
switch (PolicyHelper.GetNodeType(node))
{
case PolicyHelper.NodeType.Policy:
case PolicyHelper.NodeType.All:
nodes = ReadNode_PolicyOrAll((XmlElement)node, contextAssertion, yieldLimiter);
break;
case PolicyHelper.NodeType.ExactlyOne:
nodes = ReadNode_ExactlyOne((XmlElement)node, contextAssertion, yieldLimiter);
break;
case PolicyHelper.NodeType.Assertion:
nodes = ReadNode_Assertion((XmlElement)node, yieldLimiter);
break;
case PolicyHelper.NodeType.PolicyReference:
nodes = ReadNode_PolicyReference((XmlElement)node, contextAssertion, yieldLimiter);
break;
case PolicyHelper.NodeType.UnrecognizedWSPolicy:
string warningMsg = string.Format(SRServiceModel.UnrecognizedPolicyElementInNamespace, node.Name, node.NamespaceURI);
_metadataImporter.PolicyWarningOccured.Invoke(contextAssertion, warningMsg);
break;
//consider hsomu, add more error handling here. default?
}
return(nodes);
}