I have created a SOAP service which has some optional method arguments.
I have found some issues:
While calling the web service I always need to pass all the arguments irrespective of whether they are optional or not.
I found that in ColdFusion we can omit the optional arguments by adding omit=true in cfinvokeargument. But still we need to add cfinvokeargument for each argument. It doesn't solve much problem.
Since a web service is meant to be accessible from any platform or language, the omit=true hack may not be available in other languages.
So my question is, how to deal with the issues. Is there any way to get rid of optional arguments while calling a web service?
Related
Is it mandated by any standard that a web service should provide a WSDL by appending ?wsdl to the endpoint address?
Is it OK if the WSDL is hosted at a different URL (without appending ?wsdl)?
For example:
Endpoint: http://abc.xyz.com/MyService
WSDL: http://abc.xyz.com/MyServiceDefinition.pqr
Note that I'm even using a different extension for the WSDL definition.
Does using this approach violate any standards or one can host the thing the way they want?
Is it mandatory to have a WSDL definition accessible using ?wsdl?
No, it's not.
A WSDL is used to describe a web service contract and is provided because it allows tools to automate generation of client stub code for calling the specified web service. Exposing the WSDL at the same location as the web service with ?wsdl appended to it is just very handy and that's the convention everybody uses.
People and tools look for the WSDL at that location and frameworks automatically expose it at that location but it's just a convention. As to my knowledge this isn't specified in any specification (or at least none that I could find).
Sometimes though you don't want to provide a WSDL that everybody can look at and try to create a client because it's a private web service and you only want to give access to your partners, not to everybody. At that point you can disallow the ?wsdl URL and provide the WSDL only to your partners by using an alternative channel. You can even e-mail it if you don't want it exposed online.
So you can choose whatever channel to expose it. Just remember that because people and tools are following this convention they are used to see it there and some (poorly written) tools might choke in a different extension, for example.
P.S. One other thing I wanted to mention - which isn't strictly related to this answer but kinda reinforces the convention - is the new ?singleWsdl option in WCF 4.5.
WCF, as most other tools, exposes the WSDL at the ?wsdl address but uses xsd:import statements with external schemas. Some frameworks were not able to process WSDL with imported dependencies so people started to write customizations over WCF to have a flat WSDL exposed, so much so that in the latest version of WCF Microsoft decided to add this feature out of the box.
But for backward compatibility they needed to keep the ?wsdl endpoint as it was (returning a WSDL document with xsd:import statements inside) and were forced to add a new query parameter for the flat WSDL: ?singleWsdl. I'm sure this idea will be picked up by other web service vendors and providers as well.
No, Its not mandatory to have ?wsdl access, but its recommended way.
Its worth noting that most clients will try to append "?wsdl" to your URL and will try to access WSDL file, Hence its highly recommended to setup it.
What is the reason why hitting, for example, http:///_vti_bin/UserGroup.asmx?wsdl gives me a not full wsdl specification (if compared with http://msdn.microsoft.com/en-us/library/dd965659%28v=office.12%29.aspx)?
What I mean about not full: it does not contain some of complex types definition, e.g. User (unlike the full one), so this types are no generated by the wsdl.exe.
I have a question in regard of this: is it safe to generate c# web service stub basing on specification from MSDN or this approach is dangerous due to possible changes in contract?
For your first question as to the WSDL not being the same: it really should be equivalent and contain all the types! Whenever you append /_vti_bin/UserGroup.asmx?wsdl to your site's URL, SharePoint should definitely display the FULL WSDL, including the complex type definitions, etc. I just tried it now against my own SharePoint instance and the WSDL returned from http:// mysite.com/ ...snip... /pierre/_vti_bin/UserGroup.asmx?wsdl is pretty much the same size as the one from http://msdn.microsoft.com/en-us/library/dd965659%28v=office.12%29.aspx and a quick check to make sure complex types are in both places confirm that.
To answer your second question: I think you should NOT create your Web Service stubs and skeletons based on the WSDL in the documentation. Instead use the WSDL returned from your site. If you're not getting all the complex types in the WSDL returned from SharePoint, you should fix that issue first.
First thing I would try: download SOAPui (free) and simply plugin the URL that ends with ?wsdl and create sample requests. Maybe you'll run into access issues (UAG or other) but at least you'll know that the WSDL is well formed. If SOAPui can generate the client code based on the WSDL, you can too (using wsdl2java or the wsdl2dotnet equivalent; I can't remember the name of the .net version).
And yes, it's dangerous to copy the WSDL from the docs but I'd be more worried about some things being abbreviated or documentation going stale, etc.
As for the contract changing, I'm using the UserGroup.asmx?wsdl endpoint since 2009 and it still works on newer versions of SharePoint (even after the upgrade to SP2010). And I'm using java as the client code. Microsoft really nailed the Web Services in SharePoint, it was surprisingly easy to integrate our java stack and make calls to/from the SharePoint web services. And it was also very inter-operable with the other tools we use to test Web Services like SOAPui, etc.
Is there is any possibility (special approach or wsdl2cfc utility) to generate web service (or it’s stub) with complex input output parameters and custom failure messages based on specified WSDL? I’ve read a lot of articles which describe how to consume that type of web services, but I haven’t found any article which describes how to implement them.
you can specify the WSDL a CFC presents with the wsdlfile attribute, so you can certainly present an existing WSDL, if that's what you've got. Getting CF to map things properly when the service is invoked is another matter. I would start by taking the WSDL you have, making a CFC use it and implementing the right method names with no specified arguments and CFDUMPing the arguments structure to see what CF is getting.
You can do quite a lot to present the web service you want by using CFCs with the right names and CFPROPERTY tags in them. You can also specify in a CFARGUMENT that the type="foo[]" and the generated WSDL will expect a list of FOO objects to be passed in.
I've no experience with returning custom errors through a web service, you may have to play with what CFTHROW does from within a web service
I assume you're trying to implement a service that already exists?
We are trying to consume web services with ColdFusion.
I am able to interact with the web service for the most part, however, there is one service where ColdFusion is throwing a "Parameters Could Not Be Found" error because the response message in the WSDL for this particular service is a blank parent class. I need to add the specific parameters of corresponding subclass that inherits the class pointed to in the service of the WSDL.
Is there a way to tell ColdFusion to use a certain class definition for the parameters?
Or, is there a ColdFusion tool for showing the acceptable parameter formats for a given WSDL?
EDIT
Or, is there a way to hook into the ColdFusion code that does the parsing/conversion of the parameter structure from the WSDL?
My guess is that even finding a third-party tool will not help much because I need to know what ColdFusion is going to do, not what the data SHOULD be; I know what it should be.
You can use your own WSDL file, you don't have to use the one generated by ColdFusion, just generate one, customize it and point people to your custom WSDL file instead of the YourComponent.cfc?WSDL url.
This article on consuming complex web services may help:
http://tjordahl.blogspot.com/2008/04/reprint-consuming-web-service-complex.html
Also note that if you have a copy of Dreamweaver laying around, it has a tool for inspecting WSDL and generating the required ColdFusion code.
Or, is there a ColdFusion tool for showing the acceptable parameter formats for a given wsdl?
Please see this SO question and answer
Maybe my code samples can help you.
I have several web services in the same package that throw a custom exception. The problem is that the generated exception class contains a reference to the web service that generated it, so I can't use the same exception name across multiple web services. Is there a way to make Axis2 generate the exception classes inside the web service classes, the same way it does for other objects? I'm using ADB. I suspect that maybe there's a -E parameter, but since those aren't all documented, it's hard to say.
Here's a very good guide about Axis 2 code-generation parameters. I have used it to a number of tasks like customizing the output packages names (that by default corresponds to the WSDL namespaces).
I hope this helps you.