How to connect to a WCF Service with IronPython - wcf

Has anyone done this? I've tried generating a c# proxy class and connecting through it, but I cannot figure out how to get IronPython to use the generated app.config file that defines the endpoint. It tries to connect, but I just get an error about no default endpoint. I would ideally like to make the connection using only IronPython code and not use the proxy class, if possible. The binding for the service I am trying to connect to is a NetTcpBinding if that makes any difference.

See my blog post. There are IronPython WCF service and client examples.
To use app.config, you probably must copy it to ipy.exe and rename it to ipy.exe.config but I have not tried it so I don't know whether it works or not.

Is your WCF service interface available in a shared assembly? If so, you could look at using the ChannelFactory to create your client proxy dynamically (instead of using the generated C# proxy). With that method you can supply all the details of the endpoint when you create the ChannelFactory and you won't require any configuration in your .config file.

Related

Does WCF Add Service Reference require something configured on the service to generate the app config?

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.

Create WCF endpoint configurations in the client app, in code?

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.

Different method of consuming WCF

I have a WCF deployed on IIS. Now by adding web reference of it i am using it on my app.
So I have two questions:
Is it the best method of consuming WCF.
If the answer of first question is yes then what is the role of svcutil.exc, I mean what is the use of creating wcf proxy class. and if the answer is "No" then why?
It is the easiest solution if you develop with visual studio and have access the remote WCF service.
If you are developing using another IDE, you might want to use SvcUtil to generate your proxies.
If you prefer to have a simple CS file containing the generated client, you might also choose to generate it using SvcUtil.
You may also completely ignore SvcUtil and the Service Reference wizard and use the ChannelFactory class to generate proxies dynamically.
You should use "Add Service Reference" in Visual Studio (not Add Web Reference) for WCF.
It is the easiest way - since you can do it right in Visual Studio. What it does under the covers is basically call svcutil.exe (or you can do that manually, from the command line yourself), and create a service proxy class for use on the client side.
The use of svcutil.exe is many fold - you can create a client proxy class from a running service (or from an existing WSDL/XSD file), you can verify services, you can export metadata from a service for clients to consume, and a great many more options. It's the "Swiss Army Knife" of WCF tools.
WCF uses a concept that all calls to your service must go through a client proxy - this is the place where the entire WCF runtime lives, and where all the WCF extensibility points are located. This proxy converts your call to a method on the client into a serialized message that gets sent across the network to the server for processing, and it also handles "unpacking" the response from the call back into classes and objects on your client side for your use.
Adding a service reference is the quickest and easiest way but not always the best way. If you want performance then using ChannelFactory<T> is the way to go. You should know different ways to create a client side proxy and customisations that you can do.
An excellent resource is WcfGuidanceForWpf. Don't let the WPF in it scare you as it is really an excellent guidance for general WCF as well.

Can I add a Service Reference with netTcpBinding in WCF?

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.

Windows Communication Foundation Service Library Project

Do you know if there is any way to access the wsdl file when you create a WCF service library? It seems you can get it when you create a WCF application but not the service library...
Any ideas would be appreciated.
Thanks
The only way to access the WSDL is once you host and run the service. Otherwise, you cannot access it. So, create a host (or application as you are calling it) with a mex binding, then run the service and you should be able to access the WSDL.
Once you do this, you can save the WSDL as a file or something for later reference.
You cannot access the WSDL automatically. Of course if you compile the static WSDL into the service library, as a resource, you could then access it directly.
but what is it that you are trying to accomplish?
The "Service Description" is available inside a service. It is not the WSDL itself, but rather, the in-memory model of a service description. It includes the namespaces, the element names and types - everything in a WSDL, and more.
You can get at it with System.Web.Services.Description.ServiceDescription. Typically this is done within a ServiceHost, a ServiceHostFactory, or an IEndpointBehavior.