The Hand of FuManChu

Interesting timing on Joe Gregorio's latest foray. Lately, I've been URI-ifying all the JSON calls which etsy.com's PHP layer makes to the back end (partly with the hope that that API would be opened up to the public someday, but that isn't currently a business need). Even though the company is bucking the mainstream quite successfully, the site itself is pretty typical e-commerce. Here's what I ended up with.

Out of 298 URI's (not counting querystring variants):

• 40 are collections which support POST to add a subordinate item. Some of these are "top-level" object collections, and some are subordinate collections of data pertaining to single "objects" (e.g. /users/{user_id}/images/)
• 37 are collections which support GET to return aggregated info on all, or a subset of, their members, sometimes with search params passed in the querystring.
• 47 are traditional "objects" which support GET/PUT/DELETE on a URI of the form: /collection/subcollection/{id}, and tend to map to a database row (although many of those are virtual, being split in practice over several tables).
• 92 are URI's which GET/PUT/DELETE "object attributes", usually a single scalar each, which tend to map to single database cells. Several of these have side effects when you set/delete them.
• 34 are of the form /collection/count.
• 31 are of the form /collection/ids/.
• 20 are of the form /collection/count_and_limited_ids, which is perhaps a quirk of our architecture; at some point, I'd like to see how splitting these each into 2 calls affects performance.
• 6 are RPC-style POST URI's which I haven't had time to refactor into real noun-y resources.
• 2, I'm sad to say, are of the form DELETE /collection/{id}/cache

The URI space for this API is pretty sparse right now--these URI were simply created to replace an existing RPC-style space of procedure names. And it's essentially a single data point. However, I think it's pretty representative of e-commerce needs for RESTful JSON. One lesson might be that pagination (count and ids) should be addressed in any coordinated protocol effort.