Nested Routes and Parameters for Rails URLs (Best Practice)

Question

Hey there,

I have a decent understanding of RESTful urls and all the theory behind not nesting urls, but I'm still not quite sure how this looks in an enterprise application, like something like Amazon, StackOverflow, or Google...

Google has urls like this:

• http://code.google.com/apis/ajax/
• http://code.google.com/apis/maps/documentation/staticmaps/
• https://www.google.com/calendar/render?tab=mc

Amazon like this:

• http://www.amazon.com/books-used-books-textbooks/b/ref=sa_menu_bo0?ie=UTF8&node=283155&pf_rd_p=328655101&pf_rd_s=left-nav-1&pf_rd_t=101&pf_rd_i=507846&pf_rd_m=ATVPDKIKX0DER&pf_rd_r=1PK4ZKN4YWJJ9B86ANC9
• http://www.amazon.com/Ruby-Programming-Language-David-Flanagan/dp/0596516177/ref=sr_1_1?ie=UTF8&s=books&qid=1258755625&sr=1-1

And StackOverflow like this:

• http://stackoverflow.com/users/169992/viatropos
• http://stackoverflow.com/questions/tagged/html
• http://stackoverflow.com/questions/tagged?tagnames=html&sort=newest&pagesize=15

So my question is, what is best practice in terms of creating urls for systems like these? When do you start storing parameters in the url, when don't you? These big companies don't seem to be following the rules so hotly debated in the ruby community (that you should almost never nest URLs for example), so I'm wondering how you go about implementing your own urls in larger scale projects because it seems like the idea of not nesting urls breaks down at anything larger than a blog.

Any tips?

Answer 1

Well the first thing to realize is that if you look at the sample applications and example code out there that Rails is only good for building blogs and shopping carts.

Next you will realize that the people who advocate RESTful URLs and routes with no nesting probably are only building blogs and shopping carts.

Eventually there will be enlightenment and you will accept that RESTful URLs and non-nested routes are a bunch of bullshit and then you can get on to actually building your application and getting work done.

Answer 2

Don't get too bogged down by the "rules" in the Ruby community. The idea is that you shouldn't go overboard when nesting URLs, but when they're appropriate they're built into the Rails framework for a reason: use them.

If a resource always falls within another resource, nest it. Nothing wrong with that. Going deeper than one can sometimes be a bit of a pain because your route paths will be very long and can get a bit confusing.

Also, don't confuse nesting with namespacing. Just because you see example.com/admin/products/1234/edit does not mean that there's any nesting happening. Routing can make things look nested when they're actually not at the code level.

I'm personally a big fan of nesting and use it often (just one level -- occasionally two) in my applications. Also, adding permalink style URLs that use words rather than just IDs are more visually appealing and they can help with SEO, whether or not they're nested.

Answer 3

I believe the argument for or against REST and/or nesting in your routes has much to do with how you want to expose your API. If you do not care to ever expose an API for your app publicly, there is an argument to be made that strict adherence to RESTful design is a waste of time, particularly if you disagree with the reasoning behind REST. Your choice.

I find that thinking about how a client (other than a browser) might access information from you app helps in the design process. One of the greatest advantages of thinking about your app's design from an API perspective is that you tend to eliminate unnecessary complexity. To me this is the root of the cautions you hear in the Rails community surrounding nested routes. I would take it as an indication that things are getting a bit complicated and it might be time to step back and rethink the approach. Systems "larger than a blog" do not have to be inherently complex. Some parts might be but you also may be surprised when you approach the design from a different perspective.

In short, consider some of the dogma you might hear from certain parts of the community as guides and signals that you may want to think more deeply about your design. Strict REST is simply another way to think about how you are structuring your application.