We are working on a WCF service which is being consumed by BPEL. When BPEL imports the WSDL, it reads the XSDs as below:
_
http://Server_Name/Service1.svc?xsd=xsd0
_http://Server_Name/Service1.svc?xsd=xsd1
_http://Server_Name/Service1.svc?xsd=xsd2
so on and so forth.
This random naming of XSDs is creating a lot of churn, as whenever there is a contract change, BPEL again reloads the entire WSDL and a random number suffix will be added to each XSD. BPEL team will have to then again open each XSD to find out the change.
Is there a way by which WCF can stop generating these random XSDs and give each XSD a proper name?
What about downloading and properly naming these XSDs during design time instead of linking to these resources? The benefit would be that schema changes are under your control. I think this is preferable as long as it remains unclear if and if so under what circumstances the BPEL engine may reload the XSDs from these resources. If the schema changes, it should me made known explicitly and a new version of the process model should be deployed.
To overcome this problem, We installed .NET 4.5 to generate single wsdl which properly names the XSDs and has no XSD import statements.
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I am working on a project where the customer has changed the way they are generating the wsdls that we consume. When I generate the service reference with using the original wsdl it appears that the DataContract attributes are being used in the reference.cs class. When I use the new wsdl it looks like the XmlSerializer attributes are being used.
This causes a problem because the Order of the elements is being enforced by the XmlElement attribute. From what I have read, the VS service generator will do this if there are schema elements used in the wsdl that are either ignored or forbidden.
Is there any way automated or other means that will highlight where these errors might be?
Thanks
I have read several posts about WSDL and SOAP but still I'm confusing the actual meanings of those terms. Now, I understand that you need to construct a request message in order to consume a webservice, would it be post or get message. When talking about SOAP based webservices, you need to communicate with a webserver via constructed XML documents that are SOAP compliant. So, you need to build that manually or using proper libraries. What about WSDL, when this thing comes in?
Wikipedia states "WSDL is often used in combination with SOAP and an XML Schema to provide Web services over the Internet. A client program connecting to a Web service can read the WSDL file to determine what operations are available on the server.". So that means that WSDL is just some file describing what services are available on webserver, and I guess, such communication must also be done using SOAP. But if I know all the webservices I use, I mean, if they are hardcoded then that means that I'm not dealing with WSDL at all. IMHO WSDL is just for very smart systems where before using webservices a program needs to read status and determine what to read. Am I right?
WSDL is a means to describe what operations (method) the webservice has as well as the input/output of those methods. In the past, way before the mobile becomes popular, WSDL is used as a means for creating what is known as a stub/proxy classes.
These classes is basically generated by specific Generator (such as WSDL2Java for Java or WSDL.exe for .NET) whose job is to read the WSDL, get the methods along with its input/output and generate a language specific classes to expose those services natively. In effect, it is hiding the SOAP messages from the user and the from the consumer of the webservice point of view, they are dealing with the native classes of their language of choice.
WebService with SOAP thus was heralded as means of integration between heterogeneous systems, allowing a communication that is language independent. For example the language for implementation for the service could be in C# but the consumer of the webservices can be in Java. If the consumer is Java programmer, by using the WSDL to auto generate the classes, the Java programmers don't even need to know the concept of SOAP or XML. All the programmers know that they are dealing with Java object.
Nowadays, SOAP is more transparent and well known than it was in the past. As a result, by choice programmer can directly code the SOAP message, bypassing the need to generate the code via WSDL
I want to download xsd specifications from a web service and automatic converting (serialize) these schemas to classes (visual studio - vb.net). If the organization that is responsible for the xsd schemas alter them in a way that only my class corresponding to the xsd have to be altered (not the rest of my code) I would like to automatic update my xsd corresponding class. Is this possible? If so, can somebody tell me how to do it?
Thanks!
I use vs2010. What I want to do is: call a web service where I can send in an input parameter to the service which specifies the xsd I want to retrieve (the service is GetShemaDefenition and returns an object with the schema specification in a string property of the object). I den have to read the xsd string from the string property and convert this to a class representation of this xsd specification. Is it possible to do this automatically? I have done this manually by using xsd.exe. If the owner organization of the xsd has altered the xsd specification, I have to test if there is a new specification, and if there is I have to build a new class representation of this xsd? Is it possible to do what I want? And how would I know if it has been a big change in the xsd which also affect other parts of my code, not just the class representation of the xsd?
Tanks a lot for your reply! So what you are saying, if I understand you correct, is that there is not a good solution for automating this functionality because if the xsd change I most likely (in some occasions’) have to change my code manually? So I have to choose, either in my application or in my intermediate service? But what is the purpose for providing the xsd in a web service? What can I use the web service for? I just wondering, maybe it is clear but I am new to web services and is eager to learn more.
Update:
Thanks! But can you explain a little bit more. What I have to do is: I use one web service where one of the properties is a string. The string is an XML inside a CDATA block. The organization which provides the web service will not pares the xml inside the CDATA block but instead forward this to another organization that will use the xml data. The organization which uses the xml data specifies the xsd schem that I have to follow to generate my xml correct. This is the xsd schema I can get from another web service. I don’t really understand what I can do with this xsd file from the web service. What can I do with it and why do I want to download it from the web service, when I can’t use it automatically? Because I have to manually do the changes when the xsd changes I can easily download the xsd schema from the organization’s home page and make the new class with xsd.exe. I understand there is something I don’t understand :o), can you pleas clarify?
What visual studio version you are using?, Normally you can click on the project's references and Add Web service. In this case Visual studio creates automatically the objects required to consume the service. you can update it any time by a right click on the reference.
However if it is very likely to change often, One solution is to implement an adapter class. use create an interface that provides the same functionality and call the actual web service. In your application you use only the proxy class and not the Web Service. Later when the web service interface changes all you have to do is to change the internals of this intermediate class.
Update:
you can use this tool to create you object model in code. Then you can compile your new object model and use it in you application. There are many complications in what you want to do and the bottom line is; when the object model changes, your code will fail. There is absolutely no way to imagine how the interface will change so while you can do all that automatically there is nothing to do if the name of a function changes.
However the answer to your situation is indirection. If you can't guaranty the stability of a external service. Why not create a stable intermediate service that calls the actual one? this way in future you don't need to touch you application. All you have to do is to modify the intermediate service while keeping it's interface compatible.
I have some WCF services and have separated out the data contracts for these services into their own assembly. I then have a client of the services that references the data contracts assembly.
I have turned on the option to Reuse types in referenced assemblies. This works, but not for collections. The proxy generator instead generates its own version of collections, even though that version is exactly the same as the one in my data contracts assembly.
Is there any way to tell the proxy generator to reuse the collections defined in my data contracts assembly rather than generating its own, redundant collection types?
If you have controll of both the server and the client, you do not need to generate a provy.
There is a good explaination in this screencast.
We have stopped using generated proxies. We have saved weeks of work compared with continually having to update the generated proxies, and debugging when the problem was that someone forgot to update the proxy.
I'm trying to use NeoLoad to generate and execute SOAP requests and upon supplying the WSDL, it doesn't seem to like the imports that they are referring to.
I'm thinking I would need to flatten the WSDL generated by the WCF service.
Are there any techniques I could use to flatten it?
I've been reading:
http://blogs.msdn.com/dotnetinterop/archive/2008/09/23/flatten-your-wsdl-with-this-custom-servicehost-for-wcf.aspx
http://blogs.thinktecture.com/cweyer/archive/2007/05/10/414840.aspx
Would this be something I should be trying out?
Yes, some clients have trouble with the (standards-compliant) way that Microsoft has implemented the WSDL and XSD.
Those two articles you mention are great starting points - they show how you can get your WCF service to render out a flattened WSDL (which includes the XSD inside it).
The same goes for WCF Extras on Codeplex, which also does a few more things in addition (most notably exporting the XML comments from your C# or VB.NET code into the WSDL). Highly recommended.