Question

I need to implement a custom event handler, which should for example handle URIs like:
– SomeAppName://SomeDomainClassName/ID to fetch a record from a database table
or
– SomeAppName://SomeControllerName/PushView/SomeAdditionalOptions to push a view controller and set additional options, for example this could be a calendar view which should be focused to show the calendar at a certain date.

I have been searching for existing REST frameworks, but so far I didn’t figure how any exising framework could allow me to define formats for URIs and map them to local classes, actions, whatever it will be.

How could I 1) define and interpret REST like URIs and 2) map them to local actions or objects, without reinventing the wheel (e.g. inheriting from RESTKit)?
Or should I end up to write my own parser? In that case, pointers to good REST like URI lex/flex are welcome.

Answer 1

What I was looking for is called an URL router in Ruby worlds. There exist a few also for Objective C, more or less useful.

I ended up to write a custom URL Router, that is like ruby URL routers just split into basically two components (router and route). For the Router part (the mapper and URL dispatcher so to say) I looked at TTURLMap, which is part of Three20, but threw away 90% of code and changed the action handling to fit my needs. It has lot’s of boilerpate code, but basically was what I needed for getting an idea for the router.

For the particular route handling I use SOCKit, which seems great and has well tested code.

Now I can for example have a local function hello which takes two params to show some values passed as URL:

Roter *router = [[Router alloc] init];
[router map:@"soc://:ident/:saySomething" toInstance:self with:@selector(hello:sayWhat:)];
[router dispatch:@"soc://3/hi"];

I’ll add blocks as well, but for most cases selectors work well, because SOCKit passes them the actual values for basic parameter types (no need to use parse the dictionary with values from the URL).