Middleware Matters

As you may know, Michi Henning and I co-authored Advanced CORBA Programming with C++, which was published nearly 7 years ago but is still selling. When it first came out, Addison-Wesley set up a mailing list that readers could use to ask Michi and me about the book. We don't get much traffic on that list anymore, but an interesting message arrived this morning. The interesting part had nothing to do with CORBA, however:

Dear Mr. Henning,

First of all it came to my attention that Mr. Vinoski has died. My condolences.

Figures -- I'm always the last to find out! ;-)

As I mention here on occasion, one of my two serious sports is frisbee freestyle (the other is basketball). This year, together with my son Ryan, I managed to place well in a couple of tournaments, so I'm very happy with the fact that I'll finish the year ranked 90th in the world, up 5 places from last year, out of 450 or so ranked players. Ryan will finish at 98th. Ryan is technically better than me, but he has fewer overall points because he missed a tournament last year. Of course, it doesn't hurt that I get to play regularly not only with Ryan, but also with Toddy Brodeur, Alan Caplin, Petri Isola, Rick Williams, and Steve Scannell, who are also Boston-area freestylers. They'll finish the year ranked 9th, 34th, 37th, 38th, and 52nd, respectively, and needless to say they're all way ahead of me in their freestyle capabilities. I consider it an honor to be able to jam with them.

I wonder if Ryan and I are the first father-son freestyle duo to be in the top 100 together?

Over in his IP Babble blog, my friend and colleague William Henry talks about putting the "service" into your services. What he wisely suggests is to avoid going through a hop or hub to perform conversions, and instead build them into the endpoints themselves. This works especially well when you employ the Chain of Responsibility pattern to create an interceptor-based design so that conversions like these are relatively easy to add, even into an already-running service.

Many enterprise service developers have fallen into the trap of believing the EAI snake oil salesmen who preach that hubs are beneficial. Such hubs have proven themselves to be overly costly to put in place, hard to deploy, hard to maintain, expensive to extend, and capable of only glacial performance. Instead of falling into the hub trap, make your endpoints smart and capable so that your applications can communicate without hubs.

Obviously this won't work if you're building a mashup or are otherwise composing services over which you have no implementation control. But in the enterprise, you normally have such control, and it only makes sense to take advantage of it whenever possible.