Okay, so here's the thing - are there situations in architecture that really push you hard, drive you to come up with something of a compromise to achieve something placed upon you outside of your control?
I know that this particularly situation comes up, it's a bit like the 'on the buzzer' round on a game show. You have to think up something really creative to get around the constraint. yes, I know, the company doesn't have mature software development processes, blah blah blah, but sometimes these things happen that push you that bit harder. Come up with a solution that doesn't feel like it's selling your sole to the devil whilst still achieving whatever underlying constraint. I've been there many times, some companies have a better setup so this situation does not arise, but most do not in my experience.
So what do you do when this happens? Is there a core approach to architecture in this situation? I believe that there is, that we can have an initial approach of core process that we can use.
My first point is based around agile projects, all software development is an agile project to one form or another - I've never seen a project where the customer is happy with the outcome and doesn't want to add to it. That's not agile, but it should be! Anyway, I digress - what if you could put the architecture together an not case about such change? What I'm saying there is expect it? Changes the mindset somewhat, it is invigorating to not be constrained by the shackles of inflexibility is it not?
There's a couple of patterns that can help - first and foremost, the factory - delay implementation detail to a later date. This is a great start - its nice to be able to not care too much about the 'how' something should be done, only the 'what'. Okay, so most people are saying 'Duh, that's obvious'. Yeah, it probably is obvious by itself.
So I'd like to introduce the strategy pattern - this is a nice way to again abstract the implementation about from the function. Again, not exactly cutting edge thinking, I know.
Join those two concepts together, and we get something that Microsoft call the 'Provider' pattern. That is music to my ears - we now have a plug-able solution where were care a lot less about implementation. Sure we need to know the intent, but if someone changes their mind, which they likely will, we are happy to accommodate (in the next phase of course)
The second important thing to have in place is unit tests. I talk about them all the time personally. It's like driving without a seat belt, sure, you probably won't have a really bad crash and cause massive injury, but there's nothing like knowing you're creating a safe environment.
The only other constraint is to use proper OO techniques for encapsulation. So for example, you never expose anything like an IList
So, that said, what if you want the architecture to be SOA? Don't care. Why not have both, or some intelligent solution?
I'm thinking that there are people out there who have similar ideas an experiences? Please leave a comment if you do!
Saturday, January 31, 2009
Real world architecture
The best software to do "x"....
Hi,
Been pulling my team together for a new project, and whilst doing so, have been looking out for software that allows us to do things properly.
Now, before I start, I have to admit, that I absolutely love TFS, and VSTS, and that really makes it difficult to look for something else out there. Being realistic, to keep costs down in the current economic climate, I have been on the look out for cheaper or free alternatives. It seems that they're few and far between these days.
So first of all - non-VSTS unit testing? Well, clearly we're going to want a mocking framework there - that one is easy - Rhino Mocks. I've used NMock, which was great, but I find that once you're used to it, Rhino is the way to go. I tried Moq but found that it was less powerful than Rhino.
Okay, second on the list - code coverage. This one is difficult, Microsoft used to have a product, Coverage Eye which I used on a few occasions, and worked really well. There's NCover - that's quite expensive now, it seems, almost to the point where I should be considering VSTS which seems a lot better. The only alternative I found was partcover - it works, but the experience isn't at all integrated. And that leads me on to another point...
Unit testing framework... Okay, so the integrated MSTest framework is pretty good, and I get why you'd move the test output to a completely different location to where you would normally run from - to run the tests in isolation. No complaints from me there. However, trying to hook code coverage in to that build location from a coverage component that wasn't IDE integrated, and thus could easily capture the test folder location, is a pain. So much so that I'd suggest that using NUnit is unfortunately a necessity. The trouble is that then we're working development from our IDE, and tests from NUnit, which fires up code coverage. Not too bad a solution, but it can be a pain.
Personally, I'd really like to see something more in the professional versions of VS, what I'm saying is that every organisation is not so big it can afford, or wants to afford the all singing all dancing solution, much as I'm sure most would if it was cheaper. I'd love to see either the integration through VS to be brought a little more to the surface to open up the free version use a little better.
As previously mentioned, I love what Microsoft has done with Team System, and TFS, really I do, and I think for corporations that are able to afford it, they will go with that model. I would given the money, no doubts. Though, the alternative at the moment is really not the most compelling - I know, you say, "Save up and buy the proper version then", but at the moment, simply that's not going to happen, which cheapens the experience.
I think that the opening up of the IDE should be a little like love, you don't know that you've got it until you set it free!
And Microsoft, keep up the good work with these tools - for the first time in a long time, they really are impressive!
