Rails%203%20In%20Action

Versioning an API
That completes everything you need to do for rate limiting in your API. Before you
make a commit, run all the specs with the rake spec to see if the API is still working:
56 examples, 0 failures, 18 pending
All good! You can commit this now:
git add .
git commit -m "Added rate limiting to the V1 API"
git push
You’ve implemented a way to stop people from making too many requests to your API,
which will possibly stop your application from being overloaded due to excessive API
requests. Next, we look at how you can implement versioning in your API.
13.4 Versioning an API
At the beginning of this chapter, we discussed how all your API routes would be under
the /api/v1/ namespace. This was because you wanted to provide a predictable outcome
of the requests to the URLs. If you go changing URLs to provide extra data or to
take away data, some API clients may malfunction. So when you want to make changes
to your API, you group them all up into logical versions.
With this separation, you can provide a link, such as /api/v1/projects.json, which
will return the attributes you’re already familiar with, as well as another path for the
next version. This second version’s path will be /api/v2/projects.json, and the difference
between the two is that you’ll change the name field to be called title instead.
Although this is potentially a trivial example, 16 it’s a great case to show off how to
make two API versions different.
13.4.1 Creating a new version
To begin the versioning process, copy these routes from config/routes.rb in your
application:
namespace :api do
namespace :v1 do
resources :projects
end
end
And place them beneath, renaming v1 to v2:
namespace :api do
namespace :v2 do
resources :projects
end
end
Now you’ll need to create a new app/controllers/api/v2 directory, which you can do
by copying app/controllers/api/v1 into that location. You’ve now got version 2 of
16 Also a tiny fraction slower than v1, given you’ll be calling a method from within another method rather
renaming it.
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