Render different controller methods as JSON in Rails 5.2 - ruby-on-rails

Question

I have a resource that renders as JSON perfectly fine at localhost:3000/gins.json from #gins = Gin.order(name: :desc).
Which will return ALL gins. However, I'd like to have a JSON response that only returns the last 4 gins, to use elsewhere. In the controller I also have:
#latestgins = Gin.order("created_at DESC").first(4)
The above would work in an index.html.erb view with <%= #latestgins.name %>, but how do I get the JSON for this? I have tried render json: #latestgins but navigating to localhost:3000/latestings.json, of course, gives a routing error.
I suspect I'm attacking this in completely the wrong way, but only just starting out with Rails API.

Answer 1

you can add respond to format json in your index method:
def index
#gins = Gin.order(name: :desc)
#latestgins = Gin.order("created_at DESC").first(4)
respond_to do |format|
format.html
format.json { render json: #latestgins }
end
end
your #latestgins is now available here : localhost:3000/gins.json
Edit
If you want a custom route to display your data, just add it in your routes:
defaults format: :json do
get 'last4gins', to: "gins#index"
end
Your data for the last 4 entries is available at http://localhost:3000/last4gins.json, at http://localhost:3000/last4gins but also at localhost:3000/gins.json
If you want to keep the gins index route clean, you can also create a custom method and remove the #latestgins from your index:
# routes
get 'last4gins', to: "gins#last4gins"
#controller
def index
#gins = Gin.order(name: :desc)
end
def last4gins
#latestgins = Gin.order("created_at DESC").first(4)
render json: #latestgins
end
Now the data is no more available at /gins.json