PolicyConversionContext Class

Definition

Namespace:

System.ServiceModel.Description

Assembly:

System.ServiceModel.dll

Defines a class used to retrieve binding assertions in metadata and to attach implementing binding elements at the appropriate scope.

public ref class PolicyConversionContext abstract

public abstract class PolicyConversionContext

type PolicyConversionContext = class

Public MustInherit Class PolicyConversionContext

Inheritance

Object

PolicyConversionContext

Examples

The following code example shows an implementation of the ImportPolicy method that writes all policy assertions to the console. The code comments describe how to locate a specific custom policy assertion, create and insert an implementing binding element, and remove the assertion from the collection.

public void ImportPolicy(MetadataImporter importer,
    PolicyConversionContext context)
{
    Console.WriteLine("The custom policy importer has been called.");
    foreach (XmlElement assertion in context.GetBindingAssertions())
    {
        Console.WriteLine(assertion.NamespaceURI + " : " + assertion.Name);
        // locate a particular assertion by Name and NamespaceURI
        XmlElement customAssertion = context.GetBindingAssertions().Find(name1, ns1);
        if (customAssertion != null)
        {
          // Found assertion; remove from collection.
          context.GetBindingAssertions().Remove(customAssertion);
          Console.WriteLine(
            "Removed our custom assertion from the imported "
            + "assertions collection and inserting our custom binding element."
          );
            // Here if you find the custom policy assertion that you are looking for,
            // add the custom binding element that handles the functionality that the policy indicates.
            // Attach it to the PolicyConversionContext.BindingElements collection.
            // For example, if the custom policy had a "speed" attribute value:
            /*
              string speed
                = customAssertion.GetAttribute(SpeedBindingElement.name2, SpeedBindingElement.ns2);
              SpeedBindingElement e = new SpeedBindingElement(speed);
              context.BindingElements.Add(e);
            */
        }

        // write assertion name in red.
        Console.ForegroundColor = ConsoleColor.Red;
        Console.WriteLine(assertion.NamespaceURI + " : " + assertion.Name);

        //write contents in gray.
        Console.WriteLine(assertion.OuterXml);
        Console.ForegroundColor = ConsoleColor.Gray;
    }
}

The following code example shows how to register IPolicyImportExtension implementations using the <policyImporters> configuration section.

<configuration>
  <system.serviceModel>
    <client>
      <metadata>
        <policyImporters>
          <extension type="CustomPolicyImporter, assembly"/>
        </policyImporters>
      </metadata>
    </client>
  </system.serviceModel>
</configuration>

The following code example demonstrates how a custom binding element can implement IPolicyExportExtension to attach a custom policy assertion to the binding assertions.

public class MyBindingElement : BindingElement, IPolicyExportExtension
{
// BindingElement implementation . . .

    public void ExportPolicy(
     MetadataExporter exporter, PolicyConversionContext context)
    {
        XmlDocument xmlDoc = new XmlDocument();
        XmlElement xmlElement =
               xmlDoc.CreateElement("MyPolicyAssertion");
        context.GetBindingAssertions().Add(xmlElement);
    }

    // Note: All custom binding elements must return a deep clone
    // to enable the run time to support multiple bindings using the
    // same custom binding.
    public override BindingElement Clone()
    {
        // this is just a placeholder
        return null;
    }

    // Call the inner property.
    public override T GetProperty<T>(BindingContext context)
    {
        return context.GetInnerProperty<T>();
    }
}

public class Program {
    public static void Main(string[] args) {
        EndpointAddress address =
            new EndpointAddress("http://localhost/metadata");
        CustomBinding customBinding =
            new CustomBinding(new BasicHttpBinding());
        customBinding.Elements.Add(new MyBindingElement());
        ContractDescription contract =
            ContractDescription.GetContract(typeof(MyContract));
        ServiceEndpoint endpoint =
            new ServiceEndpoint(contract, customBinding, address);
        MetadataExporter exporter = new WsdlExporter();
        exporter.ExportEndpoint(endpoint);
    }
}

Remarks

An implementation of the PolicyConversionContext is passed to IPolicyExportExtension and IPolicyImportExtension objects to export and import, respectively, custom policy assertions to and from metadata. On export, a collection of policy assertions are retrieved in order to add custom assertions. On import, the assertions are retrieved in order to import specific ones and configure binding elements appropriately.

• The GetBindingAssertions method returns all policy assertions that are for the binding.

• The GetFaultBindingAssertions method returns all policy assertions for a specific fault message.

• The GetMessageBindingAssertions method returns all policy assertions for a specific message.

• The GetOperationBindingAssertions method returns all policy assertions for a specific operation.

• The BindingElements property gets the binding elements for the binding being described or configured.

• The Contract property gets the contract description for which the binding is being described or configured.

Constructors

PolicyConversionContext(ServiceEndpoint)

Initializes a new instance of the PolicyConversionContext class using the specified endpoint.

Properties

BindingElements	Gets a collection of binding elements to which custom binding elements that implement policy assertions are added.
Contract	Gets the contract for the endpoint.

Methods

Equals(Object)	Determines whether the specified object is equal to the current object. (Inherited from Object)
GetBindingAssertions()	Gets a collection of policy assertions from metadata.
GetFaultBindingAssertions(FaultDescription)	Returns a collection of policy assertions for the specified SOAP fault.
GetHashCode()	Serves as the default hash function. (Inherited from Object)
GetMessageBindingAssertions(MessageDescription)	Gets a collection of policy assertions for a message.
GetOperationBindingAssertions(OperationDescription)	Returns a collection of policy assertions for the specified operation.
GetType()	Gets the Type of the current instance. (Inherited from Object)
MemberwiseClone()	Creates a shallow copy of the current Object. (Inherited from Object)
ToString()	Returns a string that represents the current object. (Inherited from Object)