THe certification can be turned into a project...
I really like this idea. (Maybe because I think I would do much better in that kind of test.) I don't know how practical it would be to do in real-life, but it is much more aligned with the skill set I think of when someone talks about an architect.
it is important to understand that the CLA exam is not looking for your complete code, but for the architecture to give someone else to implement.
You are of course correct--that is what the CLA is looking for. Much of my original post was misguided, but the one critique I do think is still applicable is the idea that an architecture should be designed and handed off to the dev team. A waterfall development process like that just doesn't work very well in my experience. (Unless you're building something that is a slight variation of something you've built 100 times before.) I don't think I would accept a job where a client wanted me to design a system and then go away while someone else implements it.
For me, architecture is a process, not a deliverable. The architecture evolves as the implementation progresses. I'll have a high-level idea of the necessary functional components, their main responsibilities, and how they'll communicate with each other, but I don't bother trying to formally define all the details of each component's api since they will change as new discoveries are made and issues come up during implementation. The architecture is done when the application is done.
You need to design the framework for the application, not the application itself.
A couple months ago I discovered a podcast called
Software Engineering Radio. This weekend I was listening to Episode 87: Software Components. In it they said something that really struck a chord with me. To paraphrase, "Code is used to
implement an architecture; it is not a good way to
express an architecture."
This is a major obstacle for me. I could explain my design to someone in an hour or two using a whiteboard and a few example vis. In the pre-exam overview I was told not to include paper documentation with the solution. I asked specifically about using hand-drawn state diagrams to illustrate allowable transitions and required transition conditions. The answer was no. In practice I'll often create the state diagram using a uml tool and paste it onto the block diagram. For the exam I'm required to communicate the design to unknown developers so they can implement it, yet the exam conditions eliminate the best way I have of doing that. I'm not sure how to deal with this in a way that results in points being awarded. Maybe I'll create a doc.vi for each component and just put notes and arrows on the block diagram to recreate a state diagram?
Therefore you do not need to have the messaging library in order to complete the exam. You could easily have documented that the application requires the messaging library (perhaps even specifying a specific one) and describe how the messaging works. You are not required to actually implement it.
No, but I'd have to give enough details that an over-the-wall developer could implement it. That means describing the details of the MessageQueue class, the Message class, and the ErrorMessage class. Then I also have to describe how they work together, how to use them in code, and how to create and use custom messages. In the end there's a lot of
telling but very little
showing.
In principle I should be able to just create the public vis with the appropriate connector pane terminals and write a short note on the bd describing its behavior. In the case of the LapDog Message Library, describing it takes almost the same amount of time as fully implementing it. (Except for the Dequeue method; that would take a couple extra minutes to implement.) Almost all of the methods in the library are very thin wrappers or getters/setters. The value (imo) of the LDM stems from its structural organization and the collaboration of the classes, not any code magic inside it. I don't see any reasonable way to use it without recreating all the vis that are used. Unfortunately, creating the classes, methods, icons, descriptions, and inheritance hierarchy takes a pretty big chunk of time, and when I finally finish that task I haven't even covered a single requirement.
Giving a specific reference to the library might help... I dunno. I know we can't
have pre-built code. I assumed that also means we can't
specify pre-built code in our solution.
(IIRC, for this submission I actually created an LDM "lite," which was a few MessageQueue methods (Dequeue included, since that is a key part of the whole thing) built around a string-variant message type. I remember a couple times being frustrated with it and wishing I had the real library.)
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Assuming anyone is bothering to continue reading this thread, don't take any of this to mean I'm opposed to certification. I doubt NI views training and certification as a primary revenue stream. I suspect it is driven by business needs. Customers want some indication of whether a consultant is worth his salt or blowing smoke, so NI created certification. I'm not particularly fond of the way the CLA is structured, but perhaps that is driven by customers too. If customers are asking for architects to do designs so they can be implemented by lower cost labor elsewhere, then maybe that's what NI should give them. Personally I think the customer will be much happier at the end of the day when the architect and developers are working together closely. If customers *are* asking NI for ivory tower architects I'd prefer they push back a little and educate customers about good software dev processes instead of enabling the customer to head down a path littered with failed projects.
