As my title may be confusing, I am a little myself. If I have a WCF service running which calls methods from class MyDataAccessLayer and I also have a DLL which I use as a reference in my project that calls methods from MyDataAccessLayer, can this be the cause to this issue:
Could not find default endpoint element that references contract 'WCFTestService.ITestService' in the ServiceModel client configuration section. This might be because no configuration file was found for your application, or because no endpoint element matching this contract could be found in the client element.
I am trying to understand WCF as much as possible, and I have checked the app.config file a thousand times and I have not seen any issues with my endpoint settings. Any thoughts?
Related
We have an existing wcf service, and I created a new project. I want to use it. I hit add service reference, pop in the URL, press OK, and it adds it as a service reference but there is no config generated.
I also tried svcutil.exe /language:cs /out:GeneratedProxy.cs /config:app.config [url] but no config is generated, only the proxy cs.
I'm using VS 2013 / .NET 4.0
My question is, is this a sign that the SVC itself has some missing data that is required to build the contracts, or is the problem with adding the service reference?
For the record I have tried unchecking the reuse types option which some questions on here have reported as fixing the problem.
Bonus question, do you think if I can't get this working that manually adding some generic default bindings and endpoint code to the web config will work?
First, the reason that why the Adding service reference generates nothing is that the WCF service is rest style service. By default, the proxy-based invocation of rest style WCF services is complex.
https://en.wikipedia.org/wiki/Representational_state_transfer
https://learn.microsoft.com/en-us/dotnet/framework/wcf/feature-details/wcf-web-http-programming-model
Calling the WCF rest style service with the client proxy is uncommon. Generally, we construct an Http request by using an HTTP client library to call the service, such as HttpClient, WebClient.
How to fix "ERR_ABORTED 400 (Bad Request)" error with Jquery call to C# WCF service?
Besides, calling the WCF rest style service with the client proxy is feasible. Please refer to my previous link.
WCF: There was no endpoint listening at, that could accept the message
Feel free to let me know if there is anything I can help with.
I am trying to consume a WCF web service from a .NET client application, and I think I need to be able to programmatically create endpoints, but I don't know how. I think I need to do this because, when I try to run the application, I am getting the following error:
Could not find default endpoint
element that references contract
'IEmailService' in the ServiceModel
client configuration section. This
might be because no configuration file
was found for your application, or
because no endpoint element matching
this contract could be found in the
client element.
While troubleshooting this error, I created a simple windows forms application, in which I try to consume the same web service. With this test application I can connect to the web service successfully, and I get a valid response. But, I can reproduce the exact error cited above within in my test app by removing the system.serviceModel node and all of its child nodes from the application's app.config file (I might not have to remove ALL of that section, I'm not sure). So, my first thought was that I need to add that section to the app.config file for the real app, and everything should be fine. Unfortunately, for ridiculous reasons that I won't get into here, that is not an option. So, I am left with having to generate this information in code, inside the client app.
I am hoping someone here can help me work through this, or can point me toward a good resource for this sort of problem.
Is it possible to create endpoint configurations in the client app, in code?
By default, when you do an Add Service Reference operation, the WCF runtime will generate the client-side proxy for you.
The simplest way to use it is to instantiate the client proxy with a constructor that takes no parameters, and just grab the info from the app.config:
YourServiceClient proxy = new YourServiceClient();
This requires the config file to have a <client> entry with your service contract - if not, you'll get the error you have.
But the client side proxy class generated by the WCF runtime also has additional constructors - one takes an endpoint address and a binding, for instance:
BasicHttpBinding binding = new BasicHttpBinding(SecurityMode.None);
EndpointAddress epa = new EndpointAddress("http://localhost:8282/basic");
YourServiceClient proxy = new YourServiceClient(binding, epa);
With this setup, no config file at all is needed - you're defining everything in code. Of course, you can also set just about any other properties of your binding and/or endpoint here in code.
An east way to consume a WCF service if you have a reference to the assembly which defines the interface, is using the System.ServiceModel.ChannelFactory class.
For example, if you would like to use BasicHttpBinding:
var emailService = ChannelFactory<IEmailService>.CreateChannel(new BasicHttpBinding(), new EndpointAddress(new Uri("http://some-uri-here.com/));
If you don't have a reference to the service assembly, then you can use one of the overloaded constructors on the generated proxy class to specify binding settings.
We currently have a WCF Service which is beginning to reach it's limits performance wise.
We have decided to add another server which will host another instance of the WCF Service.
We have web applications which must communicate with a specific server based on context... e.g. If the web application is dealing with objects from ServiceInstance1 then requests must be directed to ServiceInstance1's EndPoint. If the web application is dealing with objects from ServiceInstance2 then requests must be directed to ServiceInstance2's EndPoint.
I initially thought that a "Intermediate Service" or "Service Manager" could be created, the web application's Service Reference would be updated from the individual Service Instance to the "Intermediate Service" or "Service Manager" and said service would act as a "Broker" to the various Service Instances.
How is this accomplished?
I have currently added a ServiceReference to each service from the Manager however it seems that once a Service is "Referenced" it's types becomes specific to the that of the ServiceReference e.g.
ServiceInstance1's type's are all {ServiceInstance1}.
ServiceInstance2's type's are all {ServiceInstance2}.
I need the types to be the same on the web application end, so this obviously seems like the wrong way to do it.
I would also like that when methods are called on the client generated from referencing the "Intermediate Service" or "Service Manager" that the correct Service Instance is invoked, e.g.
IServiceManager.GetProjectById( {GUID} ) ->
Comes Back to ServiceManager ->
Determines which host has the project and returns the ProjectObject from the correct ServiceInstance.
Where ProjectObject is a Type Defined in ServiceInstance1 and ServiceInstance2.
I think the original service needs to have some of the DLL's pulled out so they can be referenced from the web application side and ServiceManager and a GenericWCF Client can be made.
If I am right hooray for me If someone can point me in the right direction I would appreciate it. If I am wrong can someone please scold me and show me how this is properly done!
The way to solve your problem is to create shared assembly with types used by both services. Reference this assembly on the client consuming your services (manager) and when creating proxies by Add service reference mark Reuse types from referenced assemblies.
What you are building is very simple message router. In WCF 4.0 there is additional support for routing services so you should check those features before developing your own. For WCF 3.5 MSDN magazine contains articles about building message router - part 1, part 2.
Just to Answer this and close it I wound up utilizing the Routing Strategy in .Net 4.0 and custom client class which I modeled after the generated classes from the Proxy.
Before I had the custom client ready I used the auto generated client code and I derived a class from it which allow me to change which service it was connecting to. I determined which service via a property which was made available on all service objects which were serialized.
Long story short this is working 100% as expected including the ServiceManager which can even be bypassed on certain calls which we allow.
We even have the ability to move a project from server to server during run time!
Thanks to everyone who helped! (Especially myself for actually doing the work without being spoon fed)
The easiest way to accomplish what you're trying to do is to stop generating your proxies using the server-hosted URL of the service. Instead, generate your proxies from the *.xsd and *.wsdl locally, and merely change the URL of the endpoint. Alternatively, you can use ChannelFactory<T> to generate proxies on-the-fly, and reference your interface .dll on the client side.
Once you've done that, you can use any common webserver load balancing technique to balance the load between the servers.
Not to put too fine a point on it, but Visual Studio's "Service Reference" is not useful, and should not be used, for services you develop. It's useful only for services developed externally, whose URL and contracts are likely to NEVER change. I personally have never had occasion to use it. For your own services, you should probably be using ChannelFactory<T> or a class based on ClientBase<T> to work out the proxies.
Is it possible to add a service reference in visual studio, which generates the local proxy class to call the WCF service when using the netTcpBinding?
As I understood it, the service reference method requires a WSDL to be exposed by the service, which is only supported by the http bindings no?
Perhaps, could I add the service reference locally in development, but then switch the configuration to use nettcp at runtime in production?
The reason I am asking is because I am hosting in a windows service (server 2003, so no WAS, and can't use IIS). And we are unable to change the permissions to do the HTTP namespace reservation ... so we can't use the HTTP bindings. NetTcp works, but in this specific case the object graph we're passing back and forth involves objects generated in the service by an EDMX model ... so we can't share it in a contract assembly.
Thanks in advance!
Simply add a binding using mexTcpBinding.
Is it possible to add a service reference in visual studio,
which generates the local proxy class to call the
WCF service when using the netTcpBinding?
Yes, most definitely!
As I understood it, the service reference method requires a WSDL
to be exposed by the service, which is only supported by the http bindings no?
No, definitely not - WCF metadata (either its own specific format, or exposed as WSDL / XSD files) is definitely available for all SOAP-based calls - regardless of their transport.
Can you show us what you have, in terms of server-side config? Most likely, you're just missing a little config setting or something - if we see what you have, we might be able to pinpoint that and help you more!
All bindings are exposed though WSDL. If you add the NETTCP bindings svcutil will atuo generate the client correctly. I haven't used it in the ADD reference in VS as i have always preferred to generate the class with svcutil.
I have a Silverlight application communicating with the server side through WCF services. Initially I had everything in the main Silverlight application, but now I wanted to factor our some classes to a separate Silverlight Class Library project. This however gave me some odd issues...
I wanted to factor the classes that does the WCF communication out to a separate project. So I:
Created a new project; Silverlight class library
Moved the classes from my Silverlight application to my Silverlight class library
Removed the Service reference in the application as I no longer call it from the app.
Added a Service reference from the class library project.
Now - compiling is fine and I get intellisense for the service stuff in the Class Library, so it seems to be fine. I also updated the service and got the updates in the Class Library.
But when running the application it fails when doing a service call giving the following error:
InvalidOperationException was unhandled by user code
Could not find default endpoint element that references contract 'MyServiceReference.IMyService' in the ServiceModel client configuration section. This might be because no configuration file was found for your application, or because no endpoint element matching this contract could be found in the client element.
Seems like it can't find the service, but why? I assume there should be no problem to have service references from a Silverlight Class Library as it allows me to add one?
IT can't find any service configuration - where do you have the config for the WCF service? By default, the client app (the EXE) will have a app.config that contains the service endpoints to connect to.
Also by default, class libraries (DLL's) don't have their own configuration but rely on their hosting app to provide the configuration for them.
So all in all - you're probably missing the config for the client endpoint. Most likely, it has been created as an app.config in the class library project, but that's not being used, really - you'll have to move the <system.serviceModel> section up to the main app's config (I'm not fluent in Silverlight, but you'll know where to put it).
Marc