Bug or feature? - Migration from legacy web service framework to Spring-ws

[James Hayes]

Hi All,

(long post i know, but I have tried to make it as consise as I can)

I am currently the in process of exchanging the guts of our web services from Glue, a legacy proprietary framework which is no longer in development to Spring-ws. My aim is to touch as little of the current web services as possible and to tailor spring-ws to my needs.

Almost everything has been running smoothly apart from one thing. The publication of WSDLs... I am unsure if the problem that I am having is a required constraint or a bug.

The publication of the WSDLs almost work as we expect them to. We have xsds and they are published within a WSDL, however our problem lies with the location under which they are published. An example:

Say we have a WSDL/Service called HelloWorld and the servlet under which it is published has the pathname "/ws/v2". I declare the bean name as "HelloWorld" and the wsdl is found under the path

/ws/v2/HelloWorld.wsdl

All well and good, but say I have another Service which is within another package which I want to declare? No problem (i thought), just declare the services as having the names

net/example/billysPackage/HelloWorld

net/example/mandysPackage/HelloWorld

Then nothing works!

The problem, as I see it, lies with how the MessageDispatcherServlet#getWsdlDefinition(HttpSer vletRequest)
method trys to locate the WSDL definitions. It uses:

WebUtils.extractFilenameFromUrlPath(request.getReq uestURI());

to find out which wsdl is being requested and the method returns

HelloWorld

which it does not find within the instance variable "wsdlDefinitions"(of type Map). Both "net/example/billysPackage/HelloWorld" and "net/example/mandysPackage/HelloWorld" do exist.

There are 3 alternative ways that I know of to get around this problem, all of which I dont like:

1) Change the name of the declaration of the WSDL bean to net-example-mandysPackage-HelloWorld

Problem: Works but looks crap and isnt really want we want

2) For each package create a new servlet
Problem:
This just make things complicated.

3) Redfine MessageDispatcherServlet and reimplement #getWsdlDefinition(HttpServletRequest)
Problem:
I have no problem with programming to an Interface, I have programmed my own endpoint for example but I have a problem with inheriting from a class that is probably likely to change and which could then create side effects.


I am not sure if this problem I have having is a bug or a required constraint (perhaps someone could tell me this) or perhaps there is a fourth possibility that I have not thought of??

Cheers,

James Hayes

[James Hayes]

Well I defined a subclass of MessageDispatcherServlet to solve my problem. I dont really like to subclass but found it to be the only way. the problem code was

WebUtils.extractFilenameFromUrlPath(request.getRequestURI()

from

    protected WsdlDefinition getWsdlDefinition(HttpServletRequest request) {
        if (HttpTransportConstants.METHOD_GET.equals(request.getMethod()) &&
                request.getRequestURI().endsWith(WSDL_SUFFIX_NAME)) {
            String fileName = WebUtils.extractFilenameFromUrlPath(request.getRequestURI());
            return (WsdlDefinition) wsdlDefinitions.get(fileName);
        }
        else {
            return null;
        }
    }

which I the changed to:

    /**
     * Defines the superclass to allow the definition of wsdls within
     * paths instead of just accepting those within the servlet. The reason
     * is so we avoid requiring to have 4 different servlets for each of the
     * paths e.g. net/dsb/commons, net/dsb/vhs3 etc.
     * 
     *  @return WsdlDefinition
     * 
     */
    protected WsdlDefinition getWsdlDefinition(HttpServletRequest request) {
        String contextPath = getContextPath();
        if (HttpTransportConstants.METHOD_GET.equals(request.getMethod()) &&
                request.getRequestURI().endsWith(WSDL_SUFFIX_NAME)) {

            String fileName = StringUtils.removeStart(request.getRequestURI(), contextPath);
            fileName = StringUtils.removeEnd(fileName, WSDL_SUFFIX_NAME);
             return (WsdlDefinition) wsdlDefinitions.get(fileName);
        }
        else {
            return null;
        }
    }

    private String getContextPath() {
        return getWebApplicationContext().getServletContext().getContextPath();
    }

I also had to refine the initialization of the instance variable

wsdlDefinitions

so it really does feel like a HACK, but it works. Any other suggestions would be great!

Cheers