Add pagination

app/controllers/api/v1/parks_controller.rb

@@ -1,5 +1,20 @@
 class Api::V1::ParksController < ApplicationController
+  DEFAULT_PAGE_SIZE = 10
+
   def index
-    render json: Park.all
+    parks = Park
+      .limit(per_page)
+      .offset((page - 1) * per_page)
+    render json: parks
+  end
+
+  private
+
+  def per_page
+    (params[:per_page].presence || DEFAULT_PAGE_SIZE).to_i
+  end
+
+  def page
+    (params[:page].presence || 1).to_i
   end
 end

spec/requests/api/v1/parks_spec.rb

@@ -2,7 +2,7 @@ require 'rails_helper'
 
 RSpec.describe "Api::V1::Parks", type: :request do
   describe "GET /index" do
-    it "returns some parks" do
+    it "returns parks" do
       get api_v1_parks_url
       expect(response).to have_http_status(:success)
       expect(response.parsed_body).to include(
@@ -16,5 +16,17 @@ RSpec.describe "Api::V1::Parks", type: :request do
         )
       )
     end
+
+    context "with pagination" do
+      it "respects page size param" do
+        get api_v1_parks_url, params: { per_page: 1 }
+        expect(response.parsed_body.size).to eq(1)
+      end
+
+      it "respects page param" do
+        get api_v1_parks_url, params: { per_page: 1, page: 2 }
+        expect(response.parsed_body.first["code"]).to eq("crla")
+      end
+    end
   end
 end