S3 deprecation warning

app/models/admin_dashboard_data.rb

@@ -42,7 +42,8 @@ class AdminDashboardData
       title_check,
       site_description_check,
       site_contact_username_check,
-      notification_email_check
+      notification_email_check,
+      s3_deprecation_warning
     ].compact
   end
 
@@ -186,4 +187,8 @@ class AdminDashboardData
     I18n.t('dashboard.ruby_version_warning') if RUBY_VERSION == '2.0.0' and RUBY_PATCHLEVEL < 247
   end
 
+  def s3_deprecation_warning
+    I18n.t('dashboard.s3_deprecation_warning') if SiteSetting.enable_s3_uploads
+  end
+
 end

config/locales/server.en.yml

@@ -694,6 +694,7 @@ en:
     consumer_email_warning: "Your site is configured to use Gmail (or another consumer email service) to send email. <a href='http://support.google.com/a/bin/answer.py?hl=en&answer=166852' target='_blank'>Gmail limits how many emails you can send</a>. Consider using an email service provider like mandrill.com to ensure email deliverability."
     site_contact_username_warning: "Enter the name of a friendly staff user account to send important automated private messages from. Update site_contact_username in <a href='/admin/site_settings'>Site Settings</a>."
     notification_email_warning: "Notification emails are not being sent from a valid email address on your domain; email delivery will be erratic and unreliable. Please set notification_email to a valid local email address in <a href='/admin/site_settings'>Site Settings</a>."
+    s3_deprecation_warning: "WARNING! Amazon S3 will soon be deprecated for image/attachment storage. Please, follow the <a href='https://meta.discourse.org/t/warning-amazon-s3-is-deprecated-in-1-3-for-image-attachment-storage/26594'>instructions</a> to migrate to local storage."
 
   content_types:
     education_new_reply:

spec/models/admin_dashboard_data_spec.rb

@@ -244,4 +244,20 @@ describe AdminDashboardData do
     end
   end
 
+  describe 's3_deprecation_warning' do
+    subject { described_class.new.s3_deprecation_warning }
+
+    it 'returns nil when using local storage' do
+      SiteSetting.stubs(:enable_s3_uploads).returns(false)
+      ENV.stubs(:[]).with('RUBY_GC_MALLOC_LIMIT').returns(90000000)
+      expect(subject).to be_nil
+    end
+
+    it 'returns a string when s3 storage' do
+      SiteSetting.stubs(:enable_s3_uploads).returns(true)
+      expect(subject).to_not be_nil
+    end
+
+  end
+
 end