Forum OpenACS Q&A: Status of SOAP Support

Hi,

I'm a little out-of-step with the OACS at the moment and wondered if anyone can give me a heads up on the status of SOAP within the project.

Specifically....

-I recall a module, SOAP-Gateway. Is this still in existence, is it a preferred method and where's the latest version?

-I do recall discussions around tclSOAP. Is this usbale with AOLServer (3 not 4 as I beleive i'll need SSL support also)? If so should this be the way to go?

-Was there also an xml-rpc module knocking around? Again, where is the latest version of that?

Many thanks in advance.

I'm in the process of working out how to commit the revised soap-gateway package that uses tDOM instead of ns_xml.  It is a straight port of the original soap-gateway package.

I am further developing "service contract to web service" (sc2ws) support.  Which means you are able to deploy a service contract implementation as a web service through a web interface.

The current method of deploying web services requires writing some procs in a library and importing it into soap-gateway.  The sc2ws approach on the other hand means you don't have to write code if you want to interact with a package through web services.  You just click a few check boxes, hit submit and a service contract implementation is then deployed as a web service.

An example of usage would be if you wanted to share your Learning objects in the LORSM package.  sc2ws would allow you to deploy the "export learning objects" service contract implementation as a web service.  This will allow LORSM to share learning objects with third party systems that also supports IMS standards.  Well this is the vision I have for it.

As a result of this I have found that the soap-gateway package doesn't handle multiple return values very well, which is the case for the majority of service contracts.  Also arrays aren't supported very well either.  These are issues that I will be working on.

HI Nick,

Thanks for made soap-gateway available now. I am very curious about implementing services using soap to access existing instructional resources from digital libraries (as you said in your vision statement).

Your tarball installs fine in my dotlrn-2-1a2 (with pgsql 7.3.5 and aolserver4) but I had error when trying to import unpublished services - interop and workspace - under maintenance section ( soap/admin ).

I think they are only typo errors but could prevent us to appreciate the package. Because there is no soap-gateway in bug-tracker could you evaluate this changes i made? Thank you.

--- /tmp/soap-gateway/tcl/soap-server-lib-procs.tcl    Thu Sep 30 00:40:00 2004
+++ soap-gateway/tcl/soap-server-lib-procs.tcl  Thu Oct 14 10:54:33 2004
@@ -615,10 +615,10 @@
            }
        } elseif { $force } {
            # update
-          error "[soap::server::lib::method_update $mid $method $idl $idl_style $proc $note"]
+          error "[soap::server::lib::method_update $mid $method $idl $idl_style $proc $note]"
        }
    }

    # return namespace id
    return $nid
-}
\ No newline at end of file
+}
--- /tmp/soap-gateway/sql/postgresql/soap-gateway-create.sql    Thu Sep 30 00:41:40 2004
+++ soap-gateway/sql/postgresql/soap-gateway-create.sql Thu Oct 14 11:11:45 2004
@@ -322,9 +322,9 @@
        v_method_id = null;

        -- get namespace count for id
-      select into v_method_id method_id
+      select namespace_id into v_method_id
        from sg_namespaces
-      where namespace_id = p_namespace_id and lower(method) = lower(p_method);
+      where namespace_id = p_namespace_id and lower(service) = lower(p_method);

        -- fix up
        if v_method_id is null then

Thanks for that Orzenil, I will apply those fixes now.  I'm still waiting on a CVS account.  Might have to ask somebody else, as Don must be busy.

Nick, now that the improved SOAP support has come out, what are your plans for the service-contract-to-web-service package?

Well, as somebody who is not a current OACS user, I'm not sure how heavily you should weight my vote in terms of adjusting your workload. That said, I do think that having a quick way to convert the rich set of functionality that OACS already provides via service contracts into web services would be pretty significant.

Out of curiousity, just how much work is involved?

I stumbled on http://shibboleth.internet2.edu/ which seems to be useful for standardizing the various external permissions solutions available with openacs/dotlrn. Maybe influences eportfolio, too?

Implementing it might give dotLRN a competitive edge.

There are at least a half dozen different XML-RPC and/or SOAP implementations for AOLserver and/or OpenACS, all in various states of completeness and quality. AFAIK no one has yet reviewed them all and put together a description of what the heck they each do and why you would want to use one or the other.

Malte,

At one point TclSOAP supported acessing the same APIs thorugh SOAP or XMLRPC. Do you know if this is still true?