Restfull api design

Question

Im currently facing the following scenario in designing an api and i'm curious what is the best choice. We have multiple levels in our routes e.g.:

GET group/:id  
GET group/type/

The problem here occurs when someone is doing a GET-request on e.g. group/type, the ../type is intrepreted as the id. Which does make sense if you consider the GET on group/ only refers to a single group. Then the correct route for the type would be group/:id/type.

However, a group can have multiple types and we need a route to simply query all group types. What is the restful way of implementing this. Should one do a GET /grouptypes route or some nasty regex stuff to test if /group/gibberish is a subroute or id ? I don't ask for some hacky ways of implementing a solution, i'm just asking what would be the best design choice if we design a restful api.

I am tagging this as Express.js question since we do implement the api in express. Nevertheless i think the above behaviour is what one would expect from a routing mechanism in frameworks of such kind.

Answer 1

I assume you routing code looks like this example, or somewhat very similar to:

...

router.get('/group/:id', middleware, controller, ...);
router.get('/group/type', middleware, controller, ...);

...

So the only thing you need to make it work, just swap these lines with each other:

...

router.get('/group/type', middleware, controller, ...);
router.get('/group/:id', middleware, controller, ...);

...

The reason is that express uses the first matching route among registered routes. Taking that fact, it is quite easy to understand that since request to the /group/type route matches both schemes - the first registered will be used.

From the REST perspective, having /group/:id for getting information about particular group is completely good. Also it is completely OK to have some specific routes like /group/total or /group/stats or whatever else for getting some general data related to all groups. I don't know what is the actual functionality of your /group/type route, but if it is endpoint for getting, for example, stats about types of all groups - that is fine.