How to expose ErrorCode values? - wcf

I have web services written on WCF. I use request/response pattern and don't use FaultException. I return an error code in response contract as string. I need to expose error codes for clients in order to clients can handle exceptions. 
For example:
Var r = client.DoSomething();
Switch (r.ErrorCode)
{
Case ERROR_CODES.SomeCode:
//TODO:
}
Clients are WS-*, not only .Net.
UPDATE:
Sorry, my English is elementary. I've tried to explain in a different way.
When I use class File, I know that this class can throws some exceptions, for example, FileNotFoundException or DirectoryNotFoundException. If I create a File service How can I tell client that my service can returns "FileNotFound" or other error codes?

We generally try and use FaultContracts.
When we cannot we use a Response object that inherits from ResponseBase. ResponseBase has 2 properties, StatusCode and StatusMessage.
In your case ErrorCode, just add this property to your data contract.

Related

How to send custom http response code back from spring cloud functions in gcp?

We are using the new gcp cloud functions using Java / Kotlin.
As in the current reference implementations, we are returning org.springframework.messaging.support.GenericMessage objects.
So our code looks like this (Kotlin):
fun generatePdfInBase64(message: Message<Map<String, Any>>): Message<*> {
val document = process(message)
val encoded = Base64.getEncoder().encodeToString(document.document)
return GenericMessage(encoded)
}
We were not able to find any way to include a custom http response code to our message, e.g. 201 or something. The function only responds 200 in case of no exception or 500.
Does someone know of a way to do this?
Best wishes
Andy
As it is mentioned at the official documentation, the HttpResponse class has a method called setStatusCode where you are able to set the number of the status as your convenience
For example:
switch (request.getMethod()) {
case "GET":
response.setStatusCode(HttpURLConnection.HTTP_OK);
writer.write("Hello world!");
break;
On the other hand the constructor of the GenericMessage receives as parameter a payload, therefore I think you can create a string with a json format and use the constructor for create your GenericMessage instance with the status response you need.
If you want to know more about the statuds codes take a look at this document.

Custom Collection null when passed through WCF Service

We have some custom collections such as this:
[Serializable]
public class OccupationCollection : Collection<Occupation>
{
}
We use these in objects like the following:
private OccupationCollection _occupations;
public OccupationCollection CurrentOccupations
{
get
{
if (this._occupations == null)
return new OccupationCollection();
else
return _occupations;
}
}
Now we are making a call to a WCF service, passing objects that contain these type of lists. The lists always end up being null in the service.
I'm pretty sure this has somthing to do with serialization or something like that.
What would the simplest solution that would require minimal changes to the existing objects to get this to work?
Have you hosted your service over HTTP?
If yes, can you use fiddler to check the HTTP traffic and confirm whether serialized version of the parameter is being sent across the wire? If yes, there can be a parameter mismatch in contract between server and client.
Also is the object holding OccupationCollection decorated with Serializable/DataContract attribute? If you have DataContract attribute, ensure that the properties that need to be serialized are marked with Datamember attribute.
More details out here..
http://blog.functionalfun.net/2009/09/if-your-wcf-service-is-unexpectedly.html

wcf message response parameter

I've read this example http://msdn.microsoft.com/en-us/library/ee476510.aspx about dynamic responses in wcf.
The sample on the bottom fit my goal pretty well. This is what i did:
[OperationContract]
[WebGet(UriTemplate = "/salaries({queryString})")]
Message GetSalaryByQuery(string queryString);
and my GetSalaryByQuery-Method:
public Message GetSalaryByQuery(string querystring)
{
if (WebOperationContext.Current.IncomingRequest.Accept == "application/json")
return WebOperationContext.Current.CreateJsonResponse<Result>(Salary.GetSalaryByQueryJson(querystring));
else
return WebOperationContext.Current.CreateAtom10Response(Salary.GetSalaryByQuery(querystring));
}
It is pretty similiar to the example i found.
But its not working however. It says that there is another parameter besides the message. I googled the message-class and it seems to me that its not possible to add an parameter to a message-response.
Is there a way to pass a parameter with the request and get a response with a message object?
Is there another way to get the dynamic response?
Thanks in advance.
I got it to work. I just deleted the Metadata-Enpoint and the behavior. My Webservice provides metadata on its own and therefore doesnt need to have the mex-Metadata defined.

WCF Unique ID for each service method call

I'm logging using log4net, and I want to log a id that is unique for each serice method call. I dont need it unique across service calls, just within a method call. Is there any built in id i can use in wcf? I don't want to manually create a guid or something at the start of the method call.
e.g.
wcfMethod(int x)
{
log("xxx");
somework
log("yyy");
}
private log(string message)
{
var frame = new StackFrame(1);
var method = frame.GetMethod();
var type = method.DeclaringType;
var name = method.Name;
var log = LogManager.GetLogger(type);
// LOG ID HERE
ThreadContext.Properties["MessageId"] = OperationContext.Current.IncomingMessageHeaders.MessageId; // SOMETHING HERE
}
I've tried OperationContext.Current.IncomingMessageHeaders.MessageId but thats always null.
I've read about wcf instance correlation but i don't need something that complicated (e.g. unique across different method calls).
Please if anyone can help that would be much apprieciated. Thanks in advance.
Plain SOAP or REST has no such identification included in messages. You must use some additional feature or transport protocol (for example MSMQ) supporting identifications of messages. In case of MessageId you have to use SOAP service with WS-Addressing and this information must be passed from client.

WCF IsOneWay=true causing problems

I have written a one-way service in php that contains one method with OperationContract( IsOneWay=true)
When I call this method from my .net client application then it gives me an error
The one-way operation returned a
non-null message with Action=''
Here is my proxy generated method :
[OperationContractAttribute(IsOneWay = true, Action = "http://192.168.1.5/zfsapi/api.php#terminateProcess")]
[XmlSerializerFormatAttribute(Style=OperationFormatStyle.Rpc, SupportFaults=true, Use=OperationFormatUse.Encoded)]
[ServiceKnownTypeAttribute(typeof(ZfsSnapshot))]
void terminateProcess(int pid);
Can anyone tell me why this error occur and solution on this?