Issue 95: Interactor for Volunteers#knight

app/controllers/volunteers_controller.rb

@@ -222,8 +222,8 @@ def knight
     end
 
     volunteer = Volunteer.find(params[:volunteer_id])
-    volunteer.admin = !volunteer.admin
-    if volunteer.save
+
+    if Knight.call(volunteer: volunteer).success?
       flash[:notice] = "#{volunteer.name} Updated to Admin: #{volunteer.admin}"
     else
       flash[:error] = "#{volunteer.errors.full_messages}"

app/interactors/knight.rb

@@ -0,0 +1,12 @@
+class Knight
+  include Interactor
+
+  delegate :subject,
+           :fail!,
+           to: :context
+
+  def call
+    subject.admin = !subject.admin
+    fail! unless subject.save
+  end
+end

spec/interactors/knight_spec.rb

@@ -0,0 +1,25 @@
+require 'rails_helper'
+
+RSpec.describe Knight do
+  describe '::call' do
+    let(:volunteer) do
+      create(:volunteer, admin: false)
+    end
+
+    subject do
+      described_class.call(
+        subject: volunteer
+      )
+    end
+
+    it 'sets the admin flad' do
+      expect(subject.success?).to eq(true)
+      expect(volunteer.reload.admin).to eq(true)
+    end
+
+    it 'fails if it cannot save the volunteer' do
+      expect(volunteer).to receive(:save).and_return false
+      expect(subject.success?).to eq(false)
+    end
+  end
+end