add created at filter logic to users finder and API

app/finders/users_finder.rb

@@ -30,6 +30,7 @@ class UsersFinder
     users = by_active(users)
     users = by_external_identity(users)
     users = by_external(users)
+    users = by_created_at(users)
     users = by_non_ldap(users)
 
     users

lib/api/users.rb

@@ -51,6 +51,8 @@ module API
         optional :active, type: Boolean, default: false, desc: 'Filters only active users'
         optional :external, type: Boolean, default: false, desc: 'Filters only external users'
         optional :blocked, type: Boolean, default: false, desc: 'Filters only blocked users'
+        optional :created_after, type: DateTime, desc: 'Return users created after the specified time'
+        optional :created_before, type: DateTime, desc: 'Return users created before the specified time'
         all_or_none_of :extern_uid, :provider
 
         # EE
@@ -61,6 +63,10 @@ module API
       get do
         authenticated_as_admin! if params[:external].present? || (params[:extern_uid].present? && params[:provider].present?)
 
+        unless current_user.admin?
+          params.except!(:created_after, :created_before)
+        end
+
         users = UsersFinder.new(current_user, params).execute
 
         authorized = can?(current_user, :read_users_list)

spec/finders/users_finder_spec.rb

@@ -63,7 +63,9 @@ describe UsersFinder do
       end
 
       it 'filters by created_at' do
-        users = described_class.new(user, created_after: 2.days.ago, created_before: Time.now + 2.days).execute
+        users = described_class.new(user,
+                                    created_after: 2.days.ago,
+                                    created_before: Time.now + 2.days).execute
 
         expect(users.count).to eq(4)
       end