I have a class, in which I have a service reference (WCF) to an ASMX web service.
This obviously generates local proxy methods such as
string DoSomething(string someParameter, string someOtherParameter)
I have a method that receives a WCF message class already representing a call to this service, which I simply need to forward
I could of course use XmlDictionaryReader to extract the information from the WCF message, deserialise into the proxy classes and pass those into the proxy method, but as these will simply get serialised back it seems very wasteful
How can I call the service using the already serialised message? (I assume I will need to modify the soap action on the incoming message)
There's a two-part series on how to build a WCF router on MSDN - maybe that helps? Seems like that's more or less what you're trying to do - use a WCF service to basically route a message on to a second service (ASMX in your case).
Marc
Related
I have a requirement where I should write WCF service that is called by another external service, which code is not under my control. I only know that my service is called by that external service in this way:
string content = client.getData("http://localhost:1111/Service.svc", param);
My service is located at the address that is actually first parameter in external service method, which means my service was called somewhere inside the body of external service method.
So, my question is - how can I be signaled inside my service that my service was called by that external service?
1) you can create two endpoint for different clients (real client and external servise)
2) you can write specific behavior and realize functionality by additional paramert which will be only into behaviors
I am using a web application as a client to invoke WCF methods using proxy.
For each request being made by client object, I need to populate few properties (declared inside request class)
Is it possible to hook a method, just before making the actual web service call.
I can't modify service code right now, Can WCF extensibility points could be leveraged in this case?
Thanks for your help.
If you want to change the properties of the method parameters, you can use an IParameterInspector to do that, since at that point you'll get an array with all parameters to be sent to the server.
If you need to change other parts of the request (such as transport or SOAP headers), an IClientMessageInspector may be the best way to go.
For more information on many extensibility points at the client side, you can check the blog series at http://blogs.msdn.com/b/carlosfigueira/archive/2011/03/14/wcf-extensibility.aspx.
I need to create a WCF service that will emulate some third-party service. That service has very complicated messages and wrappers for them, so I will simplify them in description.
I have WSDL of that service and created proxy class. But here the first problem occurs: all methods in proxy have
[System.ServiceModel.OperationContractAttribute(Action = "", ReplyAction = "*")]
So it is impossible to create WCF service with many methods: each for one method in proxy because every method must have unique Action. I think that third-party service has one method that handles all requests. And I created such method with needed KnownType attributes on RequestTypeBase and ResponceTypeBase. All proxy-class methods have one parameter of type, derived from RequestTypeBase.
And here is the main problem and question: when WCF service tries to deserialize message body, it throws an exception saying that expected elementName is "Process" (the name of my mega-method that processes all requests) but existing elementName is "RequestType1" (the name class with data that must be passed to "Process" method as parameter). So how can I receive such message?? Is there some attribute in WCF to not require the methodName as root of Message body? And I even not understand for what does WCF need that MethodName there if he already knows what method is called? Looks like redundancy with action specification.
Maybe simple MessabeBody example that is successfully processing by WCF, will help to understand what I mean:
<s:Body>
<TestMethod xmlns="someNamespace">
<x>1</x>
<str>param2</str>
</TestMethod>
</s:Body>
You could skip WCF deserialization completely on the service side by using the "universal service contract":
[ServiceContract]
public interface IUniversalRequestResponseContract
{
[OperationContract(Action="*", ReplyAction="*")]
Message ProcessMessage(Message msg);
}
and then handle deserialization yourself working with the Message instance received.
If you are writing a stub emulation of some external service for testing purposes (I'm guessing), that is a good approach anyway because you can control exactly what is sent in the response.
Microsofts's WCF is easy to work with when you create Web services where each message has it's own Web method. WCF generates all of the WSDL and everything is easy.
What I want to do is have one Web method that accepts multiple different messages (I don't want to add a mew method every time I add a new message type). The messages themselves will have header information that identify the message type. Once I know the message type, I'll know the structure of the rest of the message.
The only way I've found to do this with WCF is to have the method accept a string, which I parse in as XML and and use. However, I can see no clear way to publish the various message types in the WSDL; so, the whole service is essentially undocumented.
Anyone know of a technique to use in WCF?
You can write an operation contract that accepts any message by setting the Action to * and having it take in a Message object:
[ServiceContract]
public interface IMessageContract
{
[OperationContract(Action = "*", ReplyAction = "*")]
Message ProcessRequest(Message request);
}
The Message object gives you access to the headers and has methods to deserialize the body.
To export your own WSDL, you will need to implement IWsdlExportExtension on a contract behavior or operation behavior and attach it to your service. This will give you access to a WsdlExporter, and you can create a ContractDescription yourself and call ExportContract to have it appear in the generated WSDL.
I'm developing a WCF service and if there is an error I want to serialize the incoming parameter from the original method that was called on the service. I am using IErrorHandler to catch all exceptions.
My initial thoughts were that I will store the serialized parameter in OperationContext.IncomingMessageProperties so that I can access it from the HandleError method. However, as this isn't run on the original thread I believe the OperationContext will be null, so I am considering accessing it from the ProvideFault method.
Does this seem feasible? And will it work with OneWay service calls?
Not sure I can really help you much here, but let me try:
on your client, your code basically calls a method and passes it parameters. The WCF stack on the client side then converts that into a SOAP message (typically with an XML body, but could be binary, too) with headers and all and then sends that message across the wire to the server to be processed.
The server then attempts to deserialize that message into an object and attempts to call a message on a server implementation object. That method on the server object will most likely have the same parameters again, as the client - however, there's a possibility that the call will fail before that method even gets called.
So what I'm trying to say is: you can't rely on the fact that your server-side method with its parameters really gets called - there might have been a problem with e.g. authentication, the message format, a missing header or something else, that causes the server side to fail and throw an exception even before the server-side method ever gets called.
In the end, in the IErrorHandler, there's no way I would know of to get a hold of the message and/or the method and its parameters - all you can get are the error that occured on the server, and you can use that to turn it into a SOAP fault.
What you could do - both on the client and the server side - is create a new behavior that plugs into the WCF stack, and that records the methods being called and the parameters being passed into them - by implementing a class that implements the IParameterInspector interface of WCF. But that only will get called if the message on the client and the server will get properly deserialized and the server-side method really gets called.
Check out some of these links for more info on WCF extensibility:
How to: Inspect or Modify Parameters
WCF Extensibility: Parameter Inspectors
IParameterInspector in WCF
Extending WCF with custom behaviors
Hope this helps a bit!
Marc