R – How to emit bare XML for a [WebGet] method in WCF

netwcfxml-serialization

How can I define a [OperationContract] [WebGet] method to return XML that is stored in a string, without HTML encoding the string?

The application is using WCF service to return XML/XHTML content which has been stored as a string. The XML does not correspond to any specific class via [DataContract]. It is meant to be consumed by an XSLT.

[OperationContract]
[WebGet]
public XmlContent GetContent()
{
   return new XmlContent("<p>given content</p>");
}

I have this class:

[XmlRoot]
public class XmlContent : IXmlSerializable
{
    public XmlContent(string content)
    {
        this.Content = content;
    }
    public string Content { get; set; }

    #region IXmlSerializable Members

    public System.Xml.Schema.XmlSchema GetSchema()
    {
        return null;
    }

    public void ReadXml(XmlReader reader)
    {
        throw new NotImplementedException();
    }

    public void WriteXml(XmlWriter writer)
    {

        writer.WriteRaw(this.Content);
    }
    #endregion
}

But when serialized, there is a root tag the wraps the given content.

<XmlContent>
  <p>given content</p>
</XmlContent>

I know how to change the name of the root tag ([XmlRoot(ElementName = "div")]), but I need to omit the root tag, if at all possible.

I have also tried [DataContract] instead of IXmlSerializable, but it seems less flexible.

Best Answer

Return an XmlElement. You don't need IXmlSerializable. You don't need a wrapper class.

example service interface:

namespace Cheeso.Samples.Webservices._2009Jun01
{
    [ServiceContract(Namespace="urn:Cheeso.Samples.Webservices" )]
    public interface IWebGetService
    {
        [OperationContract]
        [WebGet(
                BodyStyle = WebMessageBodyStyle.Bare,
                    RequestFormat = WebMessageFormat.Xml,
                    ResponseFormat = WebMessageFormat.Xml,
                    UriTemplate = "/Greet/{greeting}")]
        XmlElement Greet(String greeting);
    }
}

service implementation:

namespace Cheeso.Samples.Webservices._2009Jun01
{
    [ServiceBehavior(Name="WcfWebGetService",
                     Namespace="urn:Cheeso.Samples.WebServices",
                     IncludeExceptionDetailInFaults=true)]

    public class WcfWebGetService : IWebGetService
    {
        public XmlElement Greet (String greeting)
        {
            string rawXml = "<p>Stuff here</p>";
            XmlDocument doc = new XmlDocument();
            doc.Load(new System.IO.StringReader(rawXml));
            return doc.DocumentElement;
        }
    }
}

See also, this similar question, but without the WebGet twist:
serializing-generic-xml-data-across-wcf-web-service-requests.

Related Solutions

C# – How to find the method that called the current method

Try this:

using System.Diagnostics;
// Get call stack
StackTrace stackTrace = new StackTrace(); 
// Get calling method name
Console.WriteLine(stackTrace.GetFrame(1).GetMethod().Name);

one-liner:

(new System.Diagnostics.StackTrace()).GetFrame(1).GetMethod().Name

It is from Get Calling Method using Reflection [C#].

REST / SOAP endpoints for a WCF service

You can expose the service in two different endpoints. the SOAP one can use the binding that support SOAP e.g. basicHttpBinding, the RESTful one can use the webHttpBinding. I assume your REST service will be in JSON, in that case, you need to configure the two endpoints with the following behaviour configuration

<endpointBehaviors>
  <behavior name="jsonBehavior">
    <enableWebScript/>
  </behavior>
</endpointBehaviors>

An example of endpoint configuration in your scenario is

<services>
  <service name="TestService">
    <endpoint address="soap" binding="basicHttpBinding" contract="ITestService"/>
    <endpoint address="json" binding="webHttpBinding"  behaviorConfiguration="jsonBehavior" contract="ITestService"/>
  </service>
</services>

so, the service will be available at

Apply [WebGet] to the operation contract to make it RESTful. e.g.

public interface ITestService
{
   [OperationContract]
   [WebGet]
   string HelloWorld(string text)
}

Note, if the REST service is not in JSON, parameters of the operations can not contain complex type.

Reply to the post for SOAP and RESTful POX(XML)

For plain old XML as return format, this is an example that would work both for SOAP and XML.

[ServiceContract(Namespace = "http://test")]
public interface ITestService
{
    [OperationContract]
    [WebGet(UriTemplate = "accounts/{id}")]
    Account[] GetAccount(string id);
}

POX behavior for REST Plain Old XML

<behavior name="poxBehavior">
  <webHttp/>
</behavior>

Endpoints

<services>
  <service name="TestService">
    <endpoint address="soap" binding="basicHttpBinding" contract="ITestService"/>
    <endpoint address="xml" binding="webHttpBinding"  behaviorConfiguration="poxBehavior" contract="ITestService"/>
  </service>
</services>

Service will be available at

REST request try it in browser,

http://www.example.com/xml/accounts/A123

SOAP request client endpoint configuration for SOAP service after adding the service reference,

  <client>
    <endpoint address="http://www.example.com/soap" binding="basicHttpBinding"
      contract="ITestService" name="BasicHttpBinding_ITestService" />
  </client>

in C#

TestServiceClient client = new TestServiceClient();
client.GetAccount("A123");

Another way of doing it is to expose two different service contract and each one with specific configuration. This may generate some duplicates at code level, however at the end of the day, you want to make it working.

Best Answer

Related Solutions

C# – How to find the method that called the current method

REST / SOAP endpoints for a WCF service

Reply to the post for SOAP and RESTful POX(XML)

Related Topic