add licenses show

app/controllers/licenses_controller.rb

@@ -4,4 +4,8 @@ class LicensesController < ApplicationController
     q = License.ransack(name_cont: params[:name])
     @licenses = q.result(distinct: true)
   end
+
+  def show
+    @license = License.find(params[:id])
+  end
 end

app/views/licenses/show.json.jbuilder

@@ -0,0 +1,3 @@
+json.id @license.id
+json.name @license.name
+json.content @license.content