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  def Softwaremaker() :
         return "William Tay", "<Challenging Conventions />"

  knownType_Serialize, about = Softwaremaker()

 Sunday, February 13, 2005

I have spent some time preparing on a topic on WSDL and I will present this in our March 2005 SgDotNet gathering.


With all the power of abstractions that most major IDEs to today offer, inner technical plumbings are often ignored and worst - Misrepresented and Misunderstood. This can lead to choosing the wrong technologies and solutions to solving specific problems. When it comes down to troubleshooting the nooks, crannies and crevices at crunch time with no extra help, nothing beats a dirty pair of hands, a hammer and a screwdriver. William attempts to get everyone's hands dirty with a detailed look at what transcends within one of the most core and matured XML Service Technologies of today.

Some of the things that will be covered:

  1. What is WSDL
  2. Critical role in Service-Orientation
  3. Core Elements and Definitions
  4. Discovery Views
  5. Best Practices (Interoperability, Extensibility, Versioning)
  6. Coming soon to a parser near you: WSDL 1.2 ? …or is it… WSDL 2.0 ? >>> If we have time
  7. RPC-Encoding Vs Doc-Literal WSDL Concepts in Indigo >>> If we have time

If you are available or around the area on the 10th of March 2005, why not drop by Microsoft Singapore and sit in ?

The difference between this presentation and the ones I had done before for our own usergroup is that I am representing INETA APAC in this event. Thus I will be speaking in the context of a speaker from the INETA APAC Speaker Bureau. I really hope that INETA APAC can sort out some of their administrative details in time and be able to subsidize some of the pizza money for the food we intend to have. Heck, this is the only way I know how to keep some of them awake while staring at the monotonous angle brackets...

Register yourself here.

Saturday, February 12, 2005 11:41:40 PM (Malay Peninsula Standard Time, UTC+08:00)  #    Disclaimer 
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  •  Saturday, February 12, 2005

    Can anyone be surprised with Cisco's decision to enter the XML Messaging market ? With the rapid propagation of XML into the mainstream market esp in the areas of XML Messaging (aka XML SOAP Services), Middleware, Brokering, Intermediaries, it is about time customers get more choices and exposure in this arena.

    With Cisco in this segment of the market, I do expect more alternatives and choices in XML Boxes to be had by customers and them paying lesser as well.

    I still remember very clearly it was only less than 2 years back when I brought up the idea of introducing an XML Firewall into a client's environment by then Flamenco Networks (which is now acquired by Digital Evolution) and being pooed-pooed right in my face on how a text-based representation can be used for messaging and how the contents of this representation can be inspected at wire-speed at the hardware level.

    Well, Moore's Law has made it so that the price and speed of high-powered specialized processing such as XML-Encryption and XML-Digital Signature besides just plain inspecting and routing of SOAP packets can be made available to the grasp of the general masses. This will also bring forward the concept of Application-Oriented Networking into the market. I dunno BUT are we seeing another layer of abstraction into the mix now ?

    Too bad this client is not around anymore for me to say "I told you so..."

    I am very interested to see how this whole affair pans out with the middleware app-server companies such as Big Blue


    Saturday, February 12, 2005 8:28:11 AM (Malay Peninsula Standard Time, UTC+08:00)  #    Disclaimer 
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  •  Friday, February 11, 2005

    I have been a very interested observer in the recent debate between Tim and Clemens on their definition of the contract in the context of XSD/WSDL/Policy. Aaron has this to share as well which I read with great interest.

    I have done a fair amount of work in preparing to give some prezzos and talks about XSD/WSDL/Policy this year. This is the feedback I had gathered over past few months when developers questioned the reach of interoperability of XML SOAP Services...and most of the time, they have no idea what is going on with the XMLSerializer and the WSDL Generator.

    Although I am on Clemen's side when he states that:

    "Staring at WSDL is about as interesting as looking at the output of “midl /Oicf”."

    I do stand on different ground as him when I believe that developers still need to know what is going on in the deeper plumbings of things. Semantics discovery is still a distance away. While the RAD approach of VS.NET and Indigo is great in churning out developer and business productivity, the real world of the enterprise is rather different. Working in a fairly large SI give me an in-depth look at how disparate systems MUST BE made to integrate and work with each other. Introducing newer, better systems such as Indigo is not even an option at this point in time.

    WSDL-generating tools are still very primtive today. There is no easy way to really extend or version my XML SOAP Services without mucking around with the brackets of WSDL today. If you implement some kind of a proxy-middleware layer approach as a messaging layer (known as the Enterprise Service or Message Bus to some), it is highly likely that it is doing things to your XSD or WSDL to attain its advertised benefits. The point is --- You cannot run away from having to muck around with it and we are not even talking about interoperability yet.

    Clemens, however, did state his point is only valid "if you’ll be sticking to Indigo". Unfortunately, I dont have that luxury to work in an environment with a single homogeneous platform and I really doubt that will change in the real world for many years to come. So besides having to know what the wire-format looks like, it is equally important to agree to that format first and this is where XSD/WSDL/Policy comes in.

    I think Aaron hit the point in his post when he did a comparison of roles between IDL and XSD/WSDL/Policy plays in the definition of a contract. However, I would read WSDL than IDL anytime of the day.

    I believe that the WSDL generated by default (*.asmx?WSDL) from VS.NET is difficult to read and understand before it is not in-line with proper practices. Modularity, Re-usability and Separation of concerns are not being diligently practiced. That is fine, and like what Clemens say, as it is not meant to be read by many humans...but by not treating it as an official contract is totally different thing altogether.

    I think WSDL is the indispensable API and is poised to be the universal contract design view. I am a great fan of the contract-first approach and Thinktecture's WSCF, currently in the 4th rendition, is a huge step in the right direction to realize that design implementation. It does a great job in separating the data types from the message types. I cannot wait for it to go one step further in version 5 where it will generate interfaces to host the service implementation regardless of where the implementation may be, amongst other things. Thanks Christian for listening to my pleas.

    And if you are not debating the fact that WSDL is the contract but it is the readability you are having an issue with, there are a couple of ways to make a WSDL easier to read. If you are having trouble with the brackets, then why not try the {curly} ones instead. I used CapeClear's Simplified WSDL Stylesheet to bend the angles into curls.

    And of course, some people from the other camp do share the same views as well.

    Barring any further whopping from Rich Salz on WSDL 2.0, I think some of the recommendations of WSDL 2.0 does make it slightly flatter and therefore easier on the eyes. Examples include:

    1. Removal of Message Constructs -- It is more or less redundant now with Doc/Literal in wide acceptance now and is rightfully placed in the section.
    2. Renaming of PortTypes to Interfaces and Port to Endpoint can give a Software / XML SOAP Service geek orgasms.
    3. Introducing XML Schema model XSD-type enhancements such as wsdl:import and wsdl:include does bring about certain principles of modularity, re-usability and separation of concerns.
    4. ...


    Friday, February 11, 2005 2:56:39 AM (Malay Peninsula Standard Time, UTC+08:00)  #    Disclaimer 
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  •  Monday, February 07, 2005

    Michael Liebow, VP of Web Services at IBM Global Services has a great entry on his weblog where he asked if "Customers really want an SOA". This is really a great post and I couldnt agree more.

    He stated that Service Oriented Modeling and Architecture (SOMA) provides an approach to building an SOA that aligns to the business goals. It helps customers tie business processes to underlying applications to help the business realize benefits more rapidly. However, the key differentiator for SOMA is where the discussion starts. It's with the business problem.

    He makes a few quoteworthy notes worth repeating:

    1. "...businesses need better visibility into their business processes. Breaking the business down into component view -- from a discrete process or the business processes supporting the entire enterprise -- is critical to achieving business improvement and growth..."
    2. "...Business process modeling will map out a companies' business processes and help determine which business processes provide strategic differentiation over competitors, what processes are core and what business processes may not be considered strategic..."
    3. "...Once the business process change or enhancement aimed at growth has been identified, the technology conversation can now begin..."
    4. "...Customers need to approach building an SOA based on the needs of the business. A detailed identification and prioritization of services that a business needs to develop or expose to support improved business processes must be developed..."
    5. "...Evolving an SOA across the enterprise frees up IT resources and helps to ensure that investments in technology are focused on core capabilities aimed at growing the business..."
    6. "...An SOA is a roadmap. It's a means to an end. What they are demanding is flexibility..."

    Like what I have always been saying in my presentation and consulting rounds, and many-a-times conflicting to what a lot of people believe, when what they all want is just to implement XML and SOAP Services OR to be seen jumping on the SO(A) bandwagon so to look and seen to be in-tune with the times. Sometimes, people think they are implementing a SO(A) when all they are doing is just implement a SOAP interface to their data-element-layer. In other words, this isn't any different from implementing an n-tier architecture.

    --- The goal of every business should be to build an agile business system framework to better adapt itself to its ever-changing business environments; And like what Mike mentioned in point [6] above, an SO(A) is the current best approach to build that agility.

    Monday, February 07, 2005 3:51:27 PM (Malay Peninsula Standard Time, UTC+08:00)  #    Disclaimer 
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  • OASIS ratifies UDDI version 3 as Standard here
    Monday, February 07, 2005 2:45:35 PM (Malay Peninsula Standard Time, UTC+08:00)  #    Disclaimer 
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  •  Sunday, February 06, 2005

    SDA-Asia has recently published one of my articles online. In this article, I talked about how Web Services Enhancements (WSE) can be used to solve Real-World business problems with some proper thought and design processes.

    This is not as technical an article comparred to the ones I have written before, however, I feel it gives a good overview and insight to what the advanced XML services are and how to make use of some of them to solve some of the business problems of today...and needless to say, WSE 2.0 is THE tool to do that today in .NET

    I have spent a fair amount of time writing up a REAL technical article (on WSE, of course) recently which I hope will get published soon enough. Will update all once it goes live. Enjoy.

    Sunday, February 06, 2005 1:00:31 PM (Malay Peninsula Standard Time, UTC+08:00)  #    Disclaimer 
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  •  Friday, February 04, 2005

    Bill Gates talks about Microsoft's commitment to interop

    Any questions ?
    Friday, February 04, 2005 12:43:49 AM (Malay Peninsula Standard Time, UTC+08:00)  #    Disclaimer 
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  •  Monday, January 31, 2005

    If there is one guy who can do it, it is sure to be Mr Brains-and-Brawns...

    You are a devil, Casey.

    Monday, January 31, 2005 12:42:35 PM (Malay Peninsula Standard Time, UTC+08:00)  #    Disclaimer 
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  •  Saturday, January 29, 2005

    This guy is killing me. Another excellent post from him here on how to extact a RSA Public Key from a Signed Assembly.

    Nice work, William.

    Saturday, January 29, 2005 1:47:59 PM (Malay Peninsula Standard Time, UTC+08:00)  #    Disclaimer 
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  • Time and time again, I have heard many companies and people talk about how they want to adopt XML Services and (W3C) SOAP so that they can be seen moving with the times embracing Service Orientated Architectures.

    I have always stressed that it is a lot lot more than that. Just because all your applications can emit out SOAP and angle brackets and your consuming applications can "Add Web Reference" doesnt mean your business is in the realms of Service-Orientation.

    This article here puts it very nicely. It is a lot more than what most people think and it takes a longer time to understand and embrace it fully. It is very much in the business processes and very importantly, the understanding of it...and this takes a tremendous mindset change in the business thinking and culture.

    I took the liberty to quote a few snippets out:

    • "Some of the enterprises that are deftly moving toward a service-oriented architecture to exploit the potential of Web services are confronting challenges technology can't always conquer. Users say Web services still suffer from a lack of clear metadata definitions and the need for sometimes significant IT cultural changes. "
    • "Trimble learned that even using Web services, it isn't possible for the company to "gracefully and quickly" integrate systems gained in several acquisitions over the past couple of years because of the metadata problems, Denis said. "There's too much fluidity around data objects, [and] we fall back into our own nomenclature and begin to define business objects," he said. "Customer definitions are the most complex challenges for us. We support very different businesses. Our customers are major accounts, channels and end users, so it is difficult to have a one-size-fits-all definition." Until industry standards for metadata management mature, the company must tackle the metadata issues outside the SOA project, he said "
    • "But as the project has moved forward, it has been slowed by the lack of standard metadata definitions, which define and describe applications' data, "
    • "Learning noted that the migration to Web services required some cultural changes along the way, such as getting customers to change their mind-set about the way they use the system."
    • "Denis said that the company must create its own process for managing the disparate ERP systems' metadata because of a lack of tools that can automate the operation. The complex ERP network includes packages from SAP AG, Oracle Corp. and Siebel Systems Inc., some of which were gained via acquisitions."
    Saturday, January 29, 2005 8:52:29 AM (Malay Peninsula Standard Time, UTC+08:00)  #    Disclaimer 
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  • Finally, after months of waiting, Microsoft's Enterprise Library is available for download. This is essentially Avanade's famous ACA.NET version 4 which now has a official Microsoft alignment.
    Saturday, January 29, 2005 12:59:58 AM (Malay Peninsula Standard Time, UTC+08:00)  #    Disclaimer 
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  •  Friday, January 28, 2005

    Some of the folks in the Spore DotNet Usergroup got together one night to run a practical project. The idea behind the link is to build a bridge to access Visual SourceSafe over the internet. It was built successfully with the help of SCCBridge.

    Incidentally, SCCBridge relies heavily on SOAP and DIME for its purpose and it is therefore no surprise that Web Services Enhancements (WSE) 2.0 was heavily involved in use here.

    "Both the server and the client are written in C# in Microsoft Visual Studio .NET. In the project is used library SharpZipLib created by Mike Krueger (for more info see ). The algorithm for text files comparing was taken from The Code Porject site, and was written by Shankar Pratap."

    Friday, January 28, 2005 3:28:07 PM (Malay Peninsula Standard Time, UTC+08:00)  #    Disclaimer 
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  • This has been floating around for some time BUT MSFT Corp has released an official statement here

    Since XQuery is expected to reach W3C recommendation only in 2006, it won't be shipped in the upcoming .NET Framework 2.0

    I guess people like me will have to live with XSLT and XPATH for now.

    Friday, January 28, 2005 12:02:47 PM (Malay Peninsula Standard Time, UTC+08:00)  #    Disclaimer 
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