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.
Related
I have some records in the database that may or may not have some information for a certain column, and that's OK.
If a consumer of the endpoint runs into one of these records, I'd like to return "NoContent", because, well, there's No Content for that record that we can execute on. BUT ... I'd like to give them a message why, as there are two distinct reasons.
When looking at other status codes, this works:
return Accepted("I SEE THIS STRING!");
It actually shows up in the Response Header as the field location (I think, don't make me run this project again!)
This works for say Internal Server error:
return StatusCode(500, "I SEE THIS TOO!");
But, for NoContent there is no constructor like Accepted, where you can pass an object. Also, this shows me no string whatsoever:
return StatusCode(204, "WHY CAN'T I SEE THIS STRING?!");
Help!
204 (No Content) returns an HttpResponseMessage with, well, No Content.
If you do have content to return that the user can consume (the two reasons), then you don't have a No Content scenario.
Perhaps an Ok (200) with a custom ContentNotProvided class that holds a message, which can be consumed by the client, will do the trick?
Alternatively, return a BadRequest (400) with a message.
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.
I am in the process of writing a WCF webapi application and have a need to check whether an email address is taken or not. This needs to be a query the client-side code can do before attempting a PUT.
So, what I'm trying to do is use HEAD in conjunction with HTTP status codes. I am a little unsure how to go about doing that as it's a simple yes/no response which is required. So, I've used HttpResponseExceptions to return the relevant status code.
[WebInvoke(Method = "HEAD", UriTemplate = "{email}")]
[RequireAuthorisation]
public void IsEmailAddressTaken(string email)
{
if (!Regex.IsMatch(email, Regexes.EmailPattern))
{
throw new RestValidationFailureException("email", "invalid email address");
}
if (_repository.IsEmailAddressTaken(email))
{
throw new HttpResponseException(HttpStatusCode.OK);
}
throw new HttpResponseException(HttpStatusCode.NoContent);
}
This just doesn't "smell" right to me.
am I going about doing this kind of yes/no operation the right way?
My suggestion is to return a HttpResponseMessage instead of throwing exceptions.
Is your RestValidationFailureException being handled anywhere? If not, it will result in a 500 status code, which does not seem adequate.
I think it would be ok to just return OK for "exists" and 404 for "does not exist"
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.
I have a resource that looks something like this:
/users/{id}/summary?format={format}
When format is "xml" or "json" I respond with a user summary object that gets automagically encoded by WCF - fine so far. But when format equals "pdf", I want my response to consist of a trivial HTTP response body and a PDF file attachment.
How is this done? Hacking on WebOperationContext.Current.OutgoingResponse doesn't seem to work, and wouldn't be the right thing even if it did. Including the bits of the file in a CDATA section or something in the response isn't safe. Should I create a subclass of Message, then provide a custom IDispatchMessageFormatter that responds with it? I went a short distance down that path but ultimately found the documentation opaque.
What's the right thing?
It turns out that what I need is WCF "raw" mode, as described here. Broadly speaking, I want to do this:
[OperationContract, WebGet(UriTemplate = "/users/{id}/summary?format={format}"]
public Stream GetUserSummary(string id, string format)
{
if(format == "pdf")
{
WebOperationContext.Current.OutgoingResponse.ContentType = "application/pdf";
return new MemoryStream(CreatePdfSummaryFileForUser(id));
}
else
{
// XML or JSON serialization. I can't figure out a way to not do this explicitly, but my use case involved custom formatters anyway so I don't care.
}
}
In theory you could do it with a multi-part content MIME type (see http://www.faqs.org/rfcs/rfc2387.html). However, it would be much easier to return a URL in the XML/JSON response and the client can do a GET on that link to return the file.