3SidesToEveryAPI

From APIDesign

Revision as of 20:31, 23 November 2008

Not many things we know have just a single meaning. Often, depending on the point of view, there can be multiple truthful ways of describing properties of the same object. Throughout the Practical API Design book I claimed beauty is not important, however after reading Petr Hejl's recent blog post Beauty Matters, I can't do anything else then nod in agreement. Did I change my mind? Do I see why beauty matters in API design now? Well, maybe. But more importantly Petr made me realize that term API is not a single indivisible entity, it can probably have at least three different meanings.

TBD: Geometrical point is indivisible, always the same. Line, divisible, but always same. API, is interface, a line, between at least two things, as such it should be as clear line!?

Yours

The most common point of view to an API is the point of view of its users. Usually, there is much more of API users, than its writers, especially in case of successful and widely used technology. As such the amount of eyes looking from this point of view massively out-weights any other observer.

TBD: What clients see. A lot like Petr's view. API should allow its users to write beautiful code. We all want beauty, deeply inside us since Greese days. Beauty is important here, as it increases acceptance, and happiness, simplifies maintenance.

Mine

The other way to look at an API is from the point of maintainer. For us, those who maintain some API, this is the view with our own eyes. This is how we see our APIs daily - the way we design them, document them, maintain them, the way we modify all the internals hidden behind the API facade.

TBD: What the maintainer sees. Keep in mind there is one maintainer and many users. A nice facade can hide complete mess. Beware, abstractions leak. If "unmaintainability" leaks, your users will be quite upset.

The Truth

TBD: The role of the API of its own, without an observer. Can it make its every observer satisfied? It is "interface" - can it really separate its observers? Can it separate the client from the maintainer? Or client from the provider? A lot about freedom to change (each observer, without interfering with others) evolution aspects.

The Role of Beauty

Important on the "Yours"/Clients (Petr's point). Sacrify yourself if you are producers of an API (TheAPIBook's point).

TBD: Mention tribute to wikipedia::III_Sides_to_Every_Story. TBD: Category:APITypes