Jimmy Bogard - All Comments

re: How not to do Dependency Injection, in NerdDinner

Mike Chaliy — Fri, 03 Jul 2009 21:10:11 GMT

We moved to the poor-man's dependency injection from proper DI. And now I do not think that this is anti pattern(as I did before).

Primmary reasons are:

1) api usage is much more more netural...

2) consumer control creation(or access) that means that u can be lazy, an object that you depends on are also could be lazy. you can force instantiation by factory methods.. thats still much more netural.

3) you do not need materialize whole graph of dependecies... means instantiation of the controller could result to instantiation of the dep1 and dep2, but could just dep1.

4) there is no configs (implict or explict)... thats cool!

5) we are not forced to use procedure style code (services are plain bags of procedures), we can do proper OO. Composition now much more netural.

6) Public contrustors are now constructors, they are not overloaded with all dependecies.

7) YAGNI

We are looking on possibilties to move our server code to this paradigm.

re: How not to do Dependency Injection, in NerdDinner

Rod Paddock — Fri, 03 Jul 2009 19:21:11 GMT

Hey dood! This blog post was EXACTLY what I happened to be looking for in some development I am doing now. Good job!

re: How not to do Dependency Injection, in NerdDinner

Daniel Auger — Fri, 03 Jul 2009 19:20:24 GMT

Just wondering - is a container going to be used throughout the Asp.NET MVC in Action book?

re: How not to do Dependency Injection, in NerdDinner

chadmyers — Fri, 03 Jul 2009 18:52:34 GMT

If they don't want to force you to use DI/IoC, they should use their own default one (maybe embed the source from one of the micro-IoC frameworks into your code as long as its all open source).

Self-servicing dependencies via the c'tor is almost always wrong. I'd say this is one of the 'definitely wrong' cases.

re: How not to do Dependency Injection, in NerdDinner

bogardj — Fri, 03 Jul 2009 18:46:12 GMT

@Neil

Thanks, I forgot that term!

re: How not to do Dependency Injection, in NerdDinner

bogardj — Fri, 03 Jul 2009 18:45:09 GMT

@Kyle

No, in their example, I think it's quite reasonable, given the size of the app. Since it's so easy to do real DI, I don't see the pain of doing the real thing.

re: How not to do Dependency Injection, in NerdDinner

Kyle Baley — Fri, 03 Jul 2009 17:58:12 GMT

Yeah, I wouldn't fault anyone for using poor-man's dependency injection. At least not without looking at the rest of the code. It's a nice first step to get your feet wet with dependency injection, yesno? Then you can move on to maybe rolling your own DI container, then switching to a third-party one. That's just based on how I was taught, I guess.

re: How not to do Dependency Injection, in NerdDinner

Scott Muc — Fri, 03 Jul 2009 17:03:45 GMT

I personally don't see that as a terrible thing. If you know what the negatives are, it's a great way to develop a SMALL project without introducing a container.

The code is still testable because the constructor still allows the injection of fakes.

I believe this style of DI has a name. It's called "Poor Mans Dependency Injection", and I personally believe it's fine for personal projects. Whether or not it's a good thing for NerdDinner to be doing is another question. I'm sure they implemented DI that way knowing full well the negatives of that implementation.

re: How not to do Dependency Injection, in NerdDinner

Shawn Miller — Fri, 03 Jul 2009 17:01:23 GMT

Thanks for demonstrating this implementation. To be fair, the Professional ASP.NET MVC 1.0 book makes this point:

"ASP.NET MVC exposes extensibility APIs that enable developers to participate in the resolution and instantiation of controllers, and that enables Dependency Injection/IoC frameworks to be cleanly integrated within this process. Using a DI/IOC framework would also enable us to remove the default constructor from our DinnersController - which would completely remove the coupling between it and the DinnerRepositorys.

We won't be using a dependency injection/IOC framework with our NerdDinner applicaiton. But it is something we could consider for the future if the NerdDinner code-base and capabilities grew."

re: How not to do Dependency Injection, in NerdDinner

Eric Polerecky — Fri, 03 Jul 2009 16:58:18 GMT

Nice article; you show how to jump into DI with little overhead. For me; ND is a good sample of a simple way to starting to think about loose coupling without additional software.

My largest client is a very large county government; the amount of hoops I have to jump thru to use any new software is mind blowing. ND offers me a good sample to show DI...well more just loos coupling...with zero overhead (additional software)

re: How not to do Dependency Injection, in NerdDinner

Jon Kruger — Fri, 03 Jul 2009 16:35:08 GMT

They probably did it that way because they couldn't force anyone to use a specific DI container. I see other problems in MVC samples where they probably wanted to use a DI container but couldn't, so they end up with half-baked dependency injection.

re: How not to do Dependency Injection, in NerdDinner

Neil Mosafi — Fri, 03 Jul 2009 16:33:07 GMT

It's known as "poor man's dependency injection".

re: Congrats to the Los Techies MVPs!

Danilo Mendoza — Fri, 03 Jul 2009 13:26:44 GMT

Congrats to you all!!!

re: Congrats to the Los Techies MVPs!

Jeffrey Palermo — Thu, 02 Jul 2009 19:51:55 GMT

Congrats, Jimmy!!

re: Congrats to the Los Techies MVPs!

Gabriel N. Schenker — Thu, 02 Jul 2009 16:07:00 GMT

congratulations Jimmy! You deserve it.