From f5841a2fe37f956372430862416e8c5ba72423e1 Mon Sep 17 00:00:00 2001
From: Thorsten Eckel <te@zammad.com>
Date: Mon, 3 Aug 2020 10:35:43 +0200
Subject: [PATCH] Maintenance: Introduced custom Rubocop
 `Zammad/ExistsConditions` to check for `.find_by` in conditions and replace
 it with `.exists?` to increase performance and reduce memory cost.

---
 .rubocop/cop/zammad/exists_condition.rb       | 120 ++++++++++++++++++
 .rubocop/default.yml                          |   1 +
 .rubocop/rubocop_zammad.rb                    |   1 +
 app/controllers/channels_email_controller.rb  |   2 +-
 app/models/calendar.rb                        |   4 +-
 app/models/channel/driver/sms/twilio.rb       |   2 +-
 app/models/channel/driver/twitter.rb          |   6 +-
 app/models/channel/filter/identify_sender.rb  |   2 +-
 .../filter/sender_is_system_address.rb        |   2 +-
 app/models/email_address.rb                   |   2 +-
 app/models/tag/item.rb                        |   2 +-
 app/models/user.rb                            |   2 +-
 .../20150979000001_update_timestamps.rb       |   2 +-
 ...160217000001_object_manager_update_user.rb |   2 +-
 .../20160921000001_permission_active.rb.rb    |   2 +-
 ...01_organization_domain_based_assignment.rb |   2 +-
 ...17000001_job_unable_to_create_issue_432.rb |   2 +-
 ...00002_ticket_number_generator_issue_427.rb |   2 +-
 ...0003_store_config_name_update_issue_428.rb |   2 +-
 .../20161122000001_monitoring_issue_453.rb    |   2 +-
 db/migrate/20161228000001_add_taskbar_meta.rb |   2 +-
 ..._object_manager_attribute_create_middle.rb |   2 +-
 ...0113000002_slack_group_config_issue_587.rb |   2 +-
 ...16000001_add_ticket_time_accounting_373.rb |   2 +-
 db/migrate/20170116000002_fixed_typos_622.rb  |   2 +-
 ...01_unable_to_enable_time_accounting_633.rb |   2 +-
 .../20170119000001_login_email_length_650.rb  |   2 +-
 ...001_ui_ticket_zoom_article_new_internal.rb |   2 +-
 .../20170123000002_fixed_translation.rb       |   2 +-
 ...170126091128_application_secret_setting.rb |   2 +-
 ...0130000001_follow_up_possible_check_643.rb |   2 +-
 ...0001_remove_last_login_from_history_722.rb |   2 +-
 ...003_do_not_import_onw_notifications_731.rb |   2 +-
 ...07081400_ticket_state_priority_defaults.rb |   2 +-
 ..._online_browser_after_cors_csrf_changes.rb |   2 +-
 db/migrate/20170215000001_telegram_support.rb |   2 +-
 .../20170314000001_fixed_translation2.rb      |   2 +-
 ...3000001_fixed_admin_user_permission_920.rb |   2 +-
 .../20170418000001_validate_agent_limit.rb    |   2 +-
 db/migrate/20170419000001_ldap_support.rb     |   2 +-
 .../20170419000002_overview_role_ids.rb       |   2 +-
 ...170420000001_chat_increase_message_size.rb |   2 +-
 ...0170421000001_pretty_date_options_added.rb |   2 +-
 db/migrate/20170421110000_add_origin_by_id.rb |   2 +-
 db/migrate/20170426135500_add_reply_to.rb     |   2 +-
 db/migrate/20170504144100_follow_up_merged.rb |   2 +-
 db/migrate/20170515000001_scheduler_status.rb |   2 +-
 ...20170516000001_trigger_recipient_update.rb |   2 +-
 .../20170525000001_reply_to_sender_feature.rb |   2 +-
 ...00002_setting_delivery_permanent_failed.rb |   2 +-
 ...20170529132120_ldap_multi_group_mapping.rb |   2 +-
 db/migrate/20170531144425_foreign_keys.rb     |   2 +-
 .../20170608151442_enhanced_permissions.rb    |   2 +-
 db/migrate/20170619000001_tree_select.rb      |   2 +-
 .../20170626000001_locale_add_direction.rb    |   2 +-
 .../20170628000001_form_group_selection.rb    |   2 +-
 .../20170629000001_exchange_integration.rb    |   2 +-
 ...170713000001_omniauth_office365_setting.rb |   2 +-
 .../20170713000002_ticket_zoom_setting2.rb    |   2 +-
 ...0001_object_manager_user_email_optional.rb |   2 +-
 .../20170714000002_user_email_multiple_use.rb |   2 +-
 db/migrate/20170714000003_cleanup_cti_log.rb  |   2 +-
 db/migrate/20170727000001_setting_proxy.rb    |   2 +-
 db/migrate/20170816000001_idoit_support.rb    |   2 +-
 ...822000001_agend_based_sender_issue_1351.rb |   2 +-
 db/migrate/20170910000002_out_of_office2.rb   |   2 +-
 db/migrate/20170924054554_weibo_oauth2.rb     |   2 +-
 ...1_setting_send_no_auto_response_reg_exp.rb |   4 +-
 ..._char_limit_for_users_and_organizations.rb |   2 +-
 ...171023000001_fixed_store_upgrade_ror_45.rb |   2 +-
 .../20171024000001_monit_integration.rb       |   2 +-
 .../20171024000002_check_mk_integration2.rb   |   2 +-
 .../20171102000001_last_owner_update2.rb      |   2 +-
 ...mer_selection_based_on_sender_recipient.rb |   2 +-
 .../20171203000001_setting_es_pipeline.rb     |   2 +-
 .../20171206000001_setting_default_locale2.rb |   2 +-
 ...rmission_user_preferences_out_of_office.rb |   2 +-
 ...3000001_change_authorization_token_size.rb |   2 +-
 ...hange_exchange_external_sync_identifier.rb |   2 +-
 ...180111000001_ldap_samaccountname_to_uid.rb |   2 +-
 ..._ticket_number_ignore_system_id_support.rb |   2 +-
 .../20180128000001_chat_add_ip_country.rb     |   2 +-
 ...01_sidebar_customer_open_ticket_colored.rb |   2 +-
 ...80202000002_custom_ldap_login_attribute.rb |   2 +-
 ...180220000001_setting_attachment_preview.rb |   2 +-
 ...g_user_organization_selector_with_email.rb |   2 +-
 ...80220171219_check_for_object_attributes.rb |   2 +-
 ...sue_1660_fix_tree_select_configurations.rb |   2 +-
 ...180306084119_custom_html_email_css_font.rb |   2 +-
 ...00001_setting_table_group_by_show_count.rb |   2 +-
 ...ssue_1905_exchange_login_from_remote_id.rb |   2 +-
 ...tting_third_party_link_account_at_login.rb |   2 +-
 ...e_1977_remove_invalid_user_foreign_keys.rb |   2 +-
 ...80502015927_issue_1219_zhtw_locale_typo.rb |   4 +-
 ..._ticket_create_types_setting_issue_1987.rb |   2 +-
 ...01_issue2029_sipgate_integration_enable.rb |   2 +-
 ...email_forward_prefix_setting_issue_1730.rb |   2 +-
 ...0521141004_ticket_last_contact_behavior.rb |   2 +-
 db/migrate/20180524182518_sms_support.rb      |   2 +-
 ...001_issue_2035_recursive_ticket_trigger.rb |   2 +-
 ...001_setting_add_ticket_auto_assignment2.rb |   2 +-
 ...611070839_add_ux_flow_next_up_to_macros.rb |   2 +-
 ...80622140531_sequencer_log_level_setting.rb |   2 +-
 ...020509_add_group_direction_to_overviews.rb |   2 +-
 ...x_double_domain_links_in_trigger_emails.rb |   2 +-
 ...xed_twitter_ticket_article_preferences7.rb |   2 +-
 db/migrate/20180809000001_cti_generic_api.rb  |   2 +-
 ...00001_setting_delivery_temporary_failed.rb |   2 +-
 ...0911064647_issue_2140_reset_ldap_config.rb |   2 +-
 .../20180913000001_setting_add_system_bcc.rb  |   2 +-
 ...13000002_permission_add_time_accounting.rb |   2 +-
 ...00000_setting_update_pretty_date_format.rb |   2 +-
 ...00_setting_add_sipgate_alternative_fqdn.rb |   2 +-
 db/migrate/20181017000001_cti_generic_api2.rb |   2 +-
 .../20181023163804_add_stats_backends.rb      |   2 +-
 .../20181030000001_setting_add_placetel1.rb   |   2 +-
 ...08123847_add_country_attribute_to_users.rb |   2 +-
 ...nt_max_size_in_mb_setting_lower_default.rb |   2 +-
 ...68_add_indices_to_histories_and_tickets.rb |   2 +-
 ...000_setting_add_email_full_quote_header.rb |   2 +-
 ...g_change_ticket_zoom_attachment_preview.rb |   2 +-
 ...20190208000001_setting_timezone_default.rb |   2 +-
 ...nager_attribute_date_remove_future_past.rb |   2 +-
 .../20190328000000_rename_locale_on_users.rb  |   2 +-
 db/migrate/20190405000001_database_indexes.rb |   2 +-
 ...541_fix_notification_email_without_body.rb |   2 +-
 .../20190415000001_setting_es_multi_index.rb  |   2 +-
 ..._setting_ticket_number_ignore_system_id.rb |   2 +-
 ...0190531180304_initialize_knowledge_base.rb |   2 +-
 ...190626000001_setting_update_karma_level.rb |   2 +-
 db/migrate/20190715141227_saml_auth.rb        |   2 +-
 ...210244_issue_2641_kb_color_change_limit.rb |   2 +-
 ...20190718140450_forget_insecure_sessions.rb |   2 +-
 .../20190724000001_rename_reserved_words.rb   |   2 +-
 ...01_setting_postmaster_send_reject_email.rb |   2 +-
 ...te_ticket_article_body_maxlength_change.rb |   2 +-
 ...903165443_issue_2595_gitlab_placeholder.rb |   2 +-
 ...53_issue_2867_footer_header_public_link.rb |   2 +-
 .../20191001090809_create_active_job_locks.rb |   2 +-
 ...3_issue_2608_missing_trigger_permission.rb |   2 +-
 ...49_issue_2460_fix_corrupted_twitter_ids.rb |   2 +-
 ...1428_issue_2715_fix_broken_twitter_urls.rb |   2 +-
 ...0_active_job_lock_cleanup_job_scheduler.rb |   2 +-
 db/migrate/20200121000001_smime_support.rb    |   2 +-
 .../20200205000001_chat_add_allow_website.rb  |   2 +-
 .../20200401000001_service_now_config.rb      |   2 +-
 ...0200419204445_setting_websocket_backend.rb |   2 +-
 ...ication_migration_cleanup_job_scheduler.rb |   2 +-
 ...aintenance_checkmk_wordings_on_settings.rb |   2 +-
 ...9094556_issue_3110_service_now_provider.rb |   2 +-
 ...1_issue_3123_external_sync_ticket_merge.rb |   2 +-
 lib/app_version.rb                            |   2 +-
 lib/facebook.rb                               |   2 +-
 lib/import/otrs/history.rb                    |   2 +-
 lib/telegram.rb                               |   2 +-
 lib/twitter_sync.rb                           |   4 +-
 spec/lib/import/otrs/history_examples.rb      |   2 +-
 spec/support/system_init_done.rb              |   6 +-
 158 files changed, 285 insertions(+), 163 deletions(-)
 create mode 100644 .rubocop/cop/zammad/exists_condition.rb
 create mode 100644 .rubocop/rubocop_zammad.rb

diff --git a/.rubocop/cop/zammad/exists_condition.rb b/.rubocop/cop/zammad/exists_condition.rb
new file mode 100644
index 000000000..b66b10396
--- /dev/null
+++ b/.rubocop/cop/zammad/exists_condition.rb
@@ -0,0 +1,120 @@
+module RuboCop
+  module Cop
+    module Zammad
+      # This cop is used to identify usages of `find_by` in conditions and
+      # changes them to use `exists?` instead.
+      #
+      # @example
+      #   # bad
+      #   if User.find_by(name: 'Rubocop')
+      #   if !User.find_by(name: 'Rubocop')
+      #   unless User.find_by(name: 'Rubocop')
+      #   if find_by(name: 'Rubocop')
+      #   if !find_by(name: 'Rubocop')
+      #   unless find_by(name: 'Rubocop')
+      #
+      #   # good
+      #   if User.exists?(name: 'Rubocop')
+      #   if !User.exists?(name: 'Rubocop')
+      #   unless User.exists?(name: 'Rubocop')
+      #   if exists?(name: 'Rubocop')
+      #   if !exists?(name: 'Rubocop')
+      #   unless exists?(name: 'Rubocop')
+      class ExistsCondition < Cop
+
+        def_node_matcher :find_by_condition?, <<-PATTERN
+          {
+            $(send $_ :find_by ...)
+            (send $(send $_ :find_by ...) :!)
+          }
+        PATTERN
+
+        MSG = 'Use `%<prefer>s` instead of `%<current>s`.'.freeze
+
+        def on_if(node)
+          check_for_find_by(node)
+        end
+
+        def on_while(node)
+          check_for_find_by(node)
+        end
+
+        def on_while_post(node)
+          check_for_find_by(node)
+        end
+
+        def on_until(node)
+          check_for_find_by(node)
+        end
+
+        def on_until_post(node)
+          check_for_find_by(node)
+        end
+
+        def autocorrect(node)
+          lambda do |corrector|
+            corrector.replace(node.loc.selector, 'exists?')
+          end
+        end
+
+        private
+
+        def check_for_find_by(node)
+          cond = condition(node)
+          handle_node(cond)
+        end
+
+        def check_node(node)
+          return unless node
+
+          if keyword_bang?(node)
+            receiver, = *node
+
+            handle_node(receiver)
+          elsif node.operator_keyword?
+            node.each_child_node { |op| handle_node(op) }
+          elsif node.begin_type? && node.children.one?
+            handle_node(node.children.first)
+          end
+        end
+
+        def keyword_bang?(node)
+          node.respond_to?(:keyword_bang?) && node.keyword_bang?
+        end
+
+        def handle_node(node)
+          if node.send_type?
+            check_offense(*find_by_condition?(node)) # rubocop:disable Rails/DynamicFindBy
+          elsif %i[and or begin].include?(node.type)
+            check_node(node)
+          end
+        end
+
+        def condition(node)
+          if node.send_type?
+            node.receiver
+          else
+            node.condition
+          end
+        end
+
+        def check_offense(method_call = nil, receiver = nil)
+          return if method_call.nil?
+
+          add_offense(method_call,
+                      message: format(MSG,
+                                      prefer:  replacement(receiver),
+                                      current: current(receiver)))
+        end
+
+        def current(node)
+          node.respond_to?(:source) ? "#{node.source}.find_by" : 'find_by'
+        end
+
+        def replacement(node)
+          node.respond_to?(:source) ? "#{node.source}.exists?" : 'exists?'
+        end
+      end
+    end
+  end
+end
diff --git a/.rubocop/default.yml b/.rubocop/default.yml
index bc418e1d3..476aa0def 100644
--- a/.rubocop/default.yml
+++ b/.rubocop/default.yml
@@ -5,6 +5,7 @@ require:
   - rubocop-performance
   - rubocop-rails
   - rubocop-rspec
+  - ./rubocop_zammad.rb
 
 inherit_from:
   - todo.yml
diff --git a/.rubocop/rubocop_zammad.rb b/.rubocop/rubocop_zammad.rb
new file mode 100644
index 000000000..d34a735a7
--- /dev/null
+++ b/.rubocop/rubocop_zammad.rb
@@ -0,0 +1 @@
+require_relative 'cop/zammad/exists_condition'
diff --git a/app/controllers/channels_email_controller.rb b/app/controllers/channels_email_controller.rb
index 74ec24ea5..708151895 100644
--- a/app/controllers/channels_email_controller.rb
+++ b/app/controllers/channels_email_controller.rb
@@ -31,7 +31,7 @@ class ChannelsEmailController < ApplicationController
 
       email_address_ids.push email_address.id
       assets = email_address.assets(assets)
-      if !email_address.channel_id || !email_address.active || !Channel.find_by(id: email_address.channel_id)
+      if !email_address.channel_id || !email_address.active || !Channel.exists?(id: email_address.channel_id)
         not_used_email_address_ids.push email_address.id
       end
     end
diff --git a/app/models/calendar.rb b/app/models/calendar.rb
index 31f130060..5b866cd94 100644
--- a/app/models/calendar.rb
+++ b/app/models/calendar.rb
@@ -360,7 +360,7 @@ returns
 
   # check if min one is set to default true
   def min_one_check
-    if !Calendar.find_by(default: true)
+    if !Calendar.exists?(default: true)
       first = Calendar.order(:created_at, :id).limit(1).first
       return true if !first
 
@@ -376,7 +376,7 @@ returns
         sla.save!
         next
       end
-      if !Calendar.find_by(id: sla.calendar_id)
+      if !Calendar.exists?(id: sla.calendar_id)
         sla.calendar_id = default_calendar.id
         sla.save!
       end
diff --git a/app/models/channel/driver/sms/twilio.rb b/app/models/channel/driver/sms/twilio.rb
index 8f22cb6da..1ba4a7a80 100644
--- a/app/models/channel/driver/sms/twilio.rb
+++ b/app/models/channel/driver/sms/twilio.rb
@@ -33,7 +33,7 @@ class Channel::Driver::Sms::Twilio
     Rails.logger.info "Receiving SMS frim recipient #{attr[:From]}"
 
     # prevent already created articles
-    if Ticket::Article.find_by(message_id: attr[:SmsMessageSid])
+    if Ticket::Article.exists?(message_id: attr[:SmsMessageSid])
       return ['application/xml; charset=UTF-8;', Twilio::TwiML::MessagingResponse.new.to_s]
     end
 
diff --git a/app/models/channel/driver/twitter.rb b/app/models/channel/driver/twitter.rb
index d554a8ae6..2c602ebe9 100644
--- a/app/models/channel/driver/twitter.rb
+++ b/app/models/channel/driver/twitter.rb
@@ -186,7 +186,7 @@ returns
         end
 
         next if @client.locale_sender?(tweet) && own_tweet_already_imported?(tweet)
-        next if Ticket::Article.find_by(message_id: tweet.id)
+        next if Ticket::Article.exists?(message_id: tweet.id)
         break if @client.tweet_limit_reached(tweet)
 
         @client.to_group(tweet, search[:group_id], @channel)
@@ -202,7 +202,7 @@ returns
     event_time = Time.zone.now
     sleep 4
     12.times do |loop_count|
-      if Ticket::Article.find_by(message_id: tweet.id)
+      if Ticket::Article.exists?(message_id: tweet.id)
         Rails.logger.debug { "Own tweet already imported, skipping tweet #{tweet.id}" }
         return true
       end
@@ -215,7 +215,7 @@ returns
       sleep sleep_time
     end
 
-    if Ticket::Article.find_by(message_id: tweet.id)
+    if Ticket::Article.exists?(message_id: tweet.id)
       Rails.logger.debug { "Own tweet already imported, skipping tweet #{tweet.id}" }
       return true
     end
diff --git a/app/models/channel/filter/identify_sender.rb b/app/models/channel/filter/identify_sender.rb
index 022b6cb08..a1b7499dc 100644
--- a/app/models/channel/filter/identify_sender.rb
+++ b/app/models/channel/filter/identify_sender.rb
@@ -35,7 +35,7 @@ module Channel::Filter::IdentifySender
             items.each do |item|
 
               # skip if recipient is system email
-              next if EmailAddress.find_by(email: item.address.downcase)
+              next if EmailAddress.exists?(email: item.address.downcase)
 
               customer_user = user_create(
                 login:     item.address,
diff --git a/app/models/channel/filter/sender_is_system_address.rb b/app/models/channel/filter/sender_is_system_address.rb
index 4a6ee37d6..44324abd3 100644
--- a/app/models/channel/filter/sender_is_system_address.rb
+++ b/app/models/channel/filter/sender_is_system_address.rb
@@ -19,7 +19,7 @@ module Channel::Filter::SenderIsSystemAddress
 
       items = mail[form].addrs
       items.each do |item|
-        next if !EmailAddress.find_by(email: item.address.downcase)
+        next if !EmailAddress.exists?(email: item.address.downcase)
 
         mail['x-zammad-ticket-create-article-sender'.to_sym] = 'Agent'
         mail['x-zammad-article-sender'.to_sym] = 'Agent'
diff --git a/app/models/email_address.rb b/app/models/email_address.rb
index 232fada0e..060268c5f 100644
--- a/app/models/email_address.rb
+++ b/app/models/email_address.rb
@@ -63,7 +63,7 @@ check and if channel not exists reset configured channels for email addresses
   def check_if_channel_exists_set_inactive
 
     # set to active if channel exists
-    if channel_id && Channel.find_by(id: channel_id)
+    if channel_id && Channel.exists?(id: channel_id)
       self.active = true
       return true
     end
diff --git a/app/models/tag/item.rb b/app/models/tag/item.rb
index 94b1c25d8..fc3aeb9e3 100644
--- a/app/models/tag/item.rb
+++ b/app/models/tag/item.rb
@@ -49,7 +49,7 @@ Tag::Item.rename(
       Tag.where(tag_item_id: old_tag_item.id).each do |tag|
 
         # check if tag already exists on object
-        if Tag.find_by(tag_object_id: tag.tag_object_id, o_id: tag.o_id, tag_item_id: already_existing_tag.id)
+        if Tag.exists?(tag_object_id: tag.tag_object_id, o_id: tag.o_id, tag_item_id: already_existing_tag.id)
           Tag.tag_remove(
             tag_object_id: tag.tag_object_id,
             o_id:          tag.o_id,
diff --git a/app/models/user.rb b/app/models/user.rb
index 03da4f9d3..317a94da7 100644
--- a/app/models/user.rb
+++ b/app/models/user.rb
@@ -1046,7 +1046,7 @@ try to find correct name
     raise Exceptions::UnprocessableEntity, 'out of office end is required' if out_of_office_end_at.blank?
     raise Exceptions::UnprocessableEntity, 'out of office end is before start' if out_of_office_start_at > out_of_office_end_at
     raise Exceptions::UnprocessableEntity, 'out of office replacement user is required' if out_of_office_replacement_id.blank?
-    raise Exceptions::UnprocessableEntity, 'out of office no such replacement user' if !User.find_by(id: out_of_office_replacement_id)
+    raise Exceptions::UnprocessableEntity, 'out of office no such replacement user' if !User.exists?(id: out_of_office_replacement_id)
 
     true
   end
diff --git a/db/migrate/20150979000001_update_timestamps.rb b/db/migrate/20150979000001_update_timestamps.rb
index 0fdefb07c..5b2b19006 100644
--- a/db/migrate/20150979000001_update_timestamps.rb
+++ b/db/migrate/20150979000001_update_timestamps.rb
@@ -1,7 +1,7 @@
 class UpdateTimestamps < ActiveRecord::Migration[4.2]
   def up
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     # get all models
     Models.all.each_value do |value|
diff --git a/db/migrate/20160217000001_object_manager_update_user.rb b/db/migrate/20160217000001_object_manager_update_user.rb
index a5ad46081..bd151a6d6 100644
--- a/db/migrate/20160217000001_object_manager_update_user.rb
+++ b/db/migrate/20160217000001_object_manager_update_user.rb
@@ -2,7 +2,7 @@ class ObjectManagerUpdateUser < ActiveRecord::Migration[4.2]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     UserInfo.current_user_id = 1
     ObjectManager::Attribute.add(
diff --git a/db/migrate/20160921000001_permission_active.rb.rb b/db/migrate/20160921000001_permission_active.rb.rb
index d54f70803..e8bcf683f 100644
--- a/db/migrate/20160921000001_permission_active.rb.rb
+++ b/db/migrate/20160921000001_permission_active.rb.rb
@@ -1,7 +1,7 @@
 class PermissionActive < ActiveRecord::Migration[4.2]
   def up
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     add_column :permissions, :active, :boolean, null: false, default: true
 
diff --git a/db/migrate/20161112000001_organization_domain_based_assignment.rb b/db/migrate/20161112000001_organization_domain_based_assignment.rb
index f243cb352..cd17ae6e9 100644
--- a/db/migrate/20161112000001_organization_domain_based_assignment.rb
+++ b/db/migrate/20161112000001_organization_domain_based_assignment.rb
@@ -1,7 +1,7 @@
 class OrganizationDomainBasedAssignment < ActiveRecord::Migration[4.2]
   def up
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     add_column :organizations, :domain, :string, limit: 250, null: true, default: ''
     add_column :organizations, :domain_assignment, :boolean, null: false, default: false
diff --git a/db/migrate/20161117000001_job_unable_to_create_issue_432.rb b/db/migrate/20161117000001_job_unable_to_create_issue_432.rb
index 4546ac018..56411cda1 100644
--- a/db/migrate/20161117000001_job_unable_to_create_issue_432.rb
+++ b/db/migrate/20161117000001_job_unable_to_create_issue_432.rb
@@ -1,7 +1,7 @@
 class JobUnableToCreateIssue432 < ActiveRecord::Migration[4.2]
   def up
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     ActiveRecord::Migration.change_table :jobs do |t|
       t.change :timeplan, :string, limit: 2500
diff --git a/db/migrate/20161117000002_ticket_number_generator_issue_427.rb b/db/migrate/20161117000002_ticket_number_generator_issue_427.rb
index 22f87c03a..cd6e07a59 100644
--- a/db/migrate/20161117000002_ticket_number_generator_issue_427.rb
+++ b/db/migrate/20161117000002_ticket_number_generator_issue_427.rb
@@ -1,7 +1,7 @@
 class TicketNumberGeneratorIssue427 < ActiveRecord::Migration[4.2]
   def up
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     setting = Setting.find_by(name: 'ticket_number')
     setting.preferences = {
diff --git a/db/migrate/20161117000003_store_config_name_update_issue_428.rb b/db/migrate/20161117000003_store_config_name_update_issue_428.rb
index 52cd9f3b2..6fc2c40e0 100644
--- a/db/migrate/20161117000003_store_config_name_update_issue_428.rb
+++ b/db/migrate/20161117000003_store_config_name_update_issue_428.rb
@@ -1,7 +1,7 @@
 class StoreConfigNameUpdateIssue428 < ActiveRecord::Migration[4.2]
   def up
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     setting = Setting.find_by(name: 'storage')
     return if !setting
diff --git a/db/migrate/20161122000001_monitoring_issue_453.rb b/db/migrate/20161122000001_monitoring_issue_453.rb
index bebbfb817..08348f8d7 100644
--- a/db/migrate/20161122000001_monitoring_issue_453.rb
+++ b/db/migrate/20161122000001_monitoring_issue_453.rb
@@ -1,7 +1,7 @@
 class MonitoringIssue453 < ActiveRecord::Migration[4.2]
   def up
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Setting.create_if_not_exists(
       title:       'Monitoring Token',
diff --git a/db/migrate/20161228000001_add_taskbar_meta.rb b/db/migrate/20161228000001_add_taskbar_meta.rb
index a20ef07e7..1eb2a74d8 100644
--- a/db/migrate/20161228000001_add_taskbar_meta.rb
+++ b/db/migrate/20161228000001_add_taskbar_meta.rb
@@ -1,7 +1,7 @@
 class AddTaskbarMeta < ActiveRecord::Migration[4.2]
   def up
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     add_column :taskbars, :preferences, :text, limit: 5.megabytes + 1, null: true
     add_index :taskbars, [:key]
diff --git a/db/migrate/20170113000001_object_manager_attribute_create_middle.rb b/db/migrate/20170113000001_object_manager_attribute_create_middle.rb
index 7088bc2e7..6afe873eb 100644
--- a/db/migrate/20170113000001_object_manager_attribute_create_middle.rb
+++ b/db/migrate/20170113000001_object_manager_attribute_create_middle.rb
@@ -1,7 +1,7 @@
 class ObjectManagerAttributeCreateMiddle < ActiveRecord::Migration[4.2]
   def up
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     ObjectManager::Attribute.all.each do |attribute|
       next if attribute.name == 'tags'
diff --git a/db/migrate/20170113000002_slack_group_config_issue_587.rb b/db/migrate/20170113000002_slack_group_config_issue_587.rb
index 23938fe93..9712d7a90 100644
--- a/db/migrate/20170113000002_slack_group_config_issue_587.rb
+++ b/db/migrate/20170113000002_slack_group_config_issue_587.rb
@@ -2,7 +2,7 @@ class SlackGroupConfigIssue587 < ActiveRecord::Migration[4.2]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     setting = Setting.find_by(name: 'slack_config')
     return if !setting
diff --git a/db/migrate/20170116000001_add_ticket_time_accounting_373.rb b/db/migrate/20170116000001_add_ticket_time_accounting_373.rb
index e2b6adc3c..c63958e31 100644
--- a/db/migrate/20170116000001_add_ticket_time_accounting_373.rb
+++ b/db/migrate/20170116000001_add_ticket_time_accounting_373.rb
@@ -2,7 +2,7 @@ class AddTicketTimeAccounting373 < ActiveRecord::Migration[4.2]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     drop_table :ticket_time_accounting
     create_table :ticket_time_accountings do |t|
diff --git a/db/migrate/20170116000002_fixed_typos_622.rb b/db/migrate/20170116000002_fixed_typos_622.rb
index 438fd606d..992a3a790 100644
--- a/db/migrate/20170116000002_fixed_typos_622.rb
+++ b/db/migrate/20170116000002_fixed_typos_622.rb
@@ -2,7 +2,7 @@ class FixedTypos622 < ActiveRecord::Migration[4.2]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     setting = Setting.find_by(name: 'ticket_define_email_from_seperator')
     return if !setting
diff --git a/db/migrate/20170117000001_unable_to_enable_time_accounting_633.rb b/db/migrate/20170117000001_unable_to_enable_time_accounting_633.rb
index c05ba0828..37d5da470 100644
--- a/db/migrate/20170117000001_unable_to_enable_time_accounting_633.rb
+++ b/db/migrate/20170117000001_unable_to_enable_time_accounting_633.rb
@@ -2,7 +2,7 @@ class UnableToEnableTimeAccounting633 < ActiveRecord::Migration[4.2]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Setting.create_if_not_exists(
       title:       'Time Accounting',
diff --git a/db/migrate/20170119000001_login_email_length_650.rb b/db/migrate/20170119000001_login_email_length_650.rb
index 8dde12b99..71ef80b1d 100644
--- a/db/migrate/20170119000001_login_email_length_650.rb
+++ b/db/migrate/20170119000001_login_email_length_650.rb
@@ -2,7 +2,7 @@ class LoginEmailLength650 < ActiveRecord::Migration[4.2]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     change_column(:users, :login, :string, limit: 255)
     change_column(:users, :email, :string, limit: 255)
diff --git a/db/migrate/20170123000001_ui_ticket_zoom_article_new_internal.rb b/db/migrate/20170123000001_ui_ticket_zoom_article_new_internal.rb
index d29e606c9..f51a79e2a 100644
--- a/db/migrate/20170123000001_ui_ticket_zoom_article_new_internal.rb
+++ b/db/migrate/20170123000001_ui_ticket_zoom_article_new_internal.rb
@@ -2,7 +2,7 @@ class UiTicketZoomArticleNewInternal < ActiveRecord::Migration[4.2]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Setting.create_if_not_exists(
       title:       'Define default visibility of new a new article',
diff --git a/db/migrate/20170123000002_fixed_translation.rb b/db/migrate/20170123000002_fixed_translation.rb
index 4acde1979..014731d16 100644
--- a/db/migrate/20170123000002_fixed_translation.rb
+++ b/db/migrate/20170123000002_fixed_translation.rb
@@ -2,7 +2,7 @@ class FixedTranslation < ActiveRecord::Migration[4.2]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     settings_update = [
       {
diff --git a/db/migrate/20170126091128_application_secret_setting.rb b/db/migrate/20170126091128_application_secret_setting.rb
index 0fbd50075..9c703ede1 100644
--- a/db/migrate/20170126091128_application_secret_setting.rb
+++ b/db/migrate/20170126091128_application_secret_setting.rb
@@ -2,7 +2,7 @@ class ApplicationSecretSetting < ActiveRecord::Migration[4.2]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Setting.create_if_not_exists(
       title:       'Application secret',
diff --git a/db/migrate/20170130000001_follow_up_possible_check_643.rb b/db/migrate/20170130000001_follow_up_possible_check_643.rb
index 87d266552..6ca22855e 100644
--- a/db/migrate/20170130000001_follow_up_possible_check_643.rb
+++ b/db/migrate/20170130000001_follow_up_possible_check_643.rb
@@ -2,7 +2,7 @@ class FollowUpPossibleCheck643 < ActiveRecord::Migration[4.2]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Setting.create_if_not_exists(
       title:       'Define postmaster filter.',
diff --git a/db/migrate/20170203000001_remove_last_login_from_history_722.rb b/db/migrate/20170203000001_remove_last_login_from_history_722.rb
index 152d74cb6..fe84861a4 100644
--- a/db/migrate/20170203000001_remove_last_login_from_history_722.rb
+++ b/db/migrate/20170203000001_remove_last_login_from_history_722.rb
@@ -2,7 +2,7 @@ class RemoveLastLoginFromHistory722 < ActiveRecord::Migration[4.2]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     history_object = History.object_lookup('User')
     return if !history_object
diff --git a/db/migrate/20170203000003_do_not_import_onw_notifications_731.rb b/db/migrate/20170203000003_do_not_import_onw_notifications_731.rb
index 3e6198468..62058068f 100644
--- a/db/migrate/20170203000003_do_not_import_onw_notifications_731.rb
+++ b/db/migrate/20170203000003_do_not_import_onw_notifications_731.rb
@@ -2,7 +2,7 @@ class DoNotImportOnwNotifications731 < ActiveRecord::Migration[4.2]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Setting.create_if_not_exists(
       title:       'Define postmaster filter.',
diff --git a/db/migrate/20170207081400_ticket_state_priority_defaults.rb b/db/migrate/20170207081400_ticket_state_priority_defaults.rb
index 7e976ab8f..7e25748c6 100644
--- a/db/migrate/20170207081400_ticket_state_priority_defaults.rb
+++ b/db/migrate/20170207081400_ticket_state_priority_defaults.rb
@@ -2,7 +2,7 @@ class TicketStatePriorityDefaults < ActiveRecord::Migration[4.2]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     add_column :ticket_states, :default_create, :boolean, null: false, default: false
     add_index  :ticket_states, :default_create
diff --git a/db/migrate/20170214000001_reload_online_browser_after_cors_csrf_changes.rb b/db/migrate/20170214000001_reload_online_browser_after_cors_csrf_changes.rb
index f082be45b..298b3a716 100644
--- a/db/migrate/20170214000001_reload_online_browser_after_cors_csrf_changes.rb
+++ b/db/migrate/20170214000001_reload_online_browser_after_cors_csrf_changes.rb
@@ -2,7 +2,7 @@ class ReloadOnlineBrowserAfterCorsCsrfChanges < ActiveRecord::Migration[4.2]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     AppVersion.set(true, 'app_version')
   end
diff --git a/db/migrate/20170215000001_telegram_support.rb b/db/migrate/20170215000001_telegram_support.rb
index 9d4da9dba..ab733223e 100644
--- a/db/migrate/20170215000001_telegram_support.rb
+++ b/db/migrate/20170215000001_telegram_support.rb
@@ -2,7 +2,7 @@ class TelegramSupport < ActiveRecord::Migration[4.2]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Permission.create_if_not_exists(
       name:        'admin.channel_telegram',
diff --git a/db/migrate/20170314000001_fixed_translation2.rb b/db/migrate/20170314000001_fixed_translation2.rb
index e3b5eaaa8..e20e9f85e 100644
--- a/db/migrate/20170314000001_fixed_translation2.rb
+++ b/db/migrate/20170314000001_fixed_translation2.rb
@@ -2,7 +2,7 @@ class FixedTranslation2 < ActiveRecord::Migration[4.2]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     settings_update = [
       {
diff --git a/db/migrate/20170403000001_fixed_admin_user_permission_920.rb b/db/migrate/20170403000001_fixed_admin_user_permission_920.rb
index 4ca888bce..21a43a8ac 100644
--- a/db/migrate/20170403000001_fixed_admin_user_permission_920.rb
+++ b/db/migrate/20170403000001_fixed_admin_user_permission_920.rb
@@ -2,7 +2,7 @@ class FixedAdminUserPermission920 < ActiveRecord::Migration[4.2]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     ObjectManager::Attribute.add(
       force:       true,
diff --git a/db/migrate/20170418000001_validate_agent_limit.rb b/db/migrate/20170418000001_validate_agent_limit.rb
index 6c6f4fd40..1caf48eef 100644
--- a/db/migrate/20170418000001_validate_agent_limit.rb
+++ b/db/migrate/20170418000001_validate_agent_limit.rb
@@ -1,7 +1,7 @@
 class ValidateAgentLimit < ActiveRecord::Migration[4.2]
   def up
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Setting.create_if_not_exists(
       title:       'Set limit of agents',
diff --git a/db/migrate/20170419000001_ldap_support.rb b/db/migrate/20170419000001_ldap_support.rb
index c460e8757..97d3f69f8 100644
--- a/db/migrate/20170419000001_ldap_support.rb
+++ b/db/migrate/20170419000001_ldap_support.rb
@@ -2,7 +2,7 @@ class LdapSupport < ActiveRecord::Migration[4.2]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     if !ActiveRecord::Base.connection.table_exists? 'import_jobs'
       create_table :import_jobs do |t|
diff --git a/db/migrate/20170419000002_overview_role_ids.rb b/db/migrate/20170419000002_overview_role_ids.rb
index 124f8c019..5a8f625a3 100644
--- a/db/migrate/20170419000002_overview_role_ids.rb
+++ b/db/migrate/20170419000002_overview_role_ids.rb
@@ -2,7 +2,7 @@ class OverviewRoleIds < ActiveRecord::Migration[4.2]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     create_table :overviews_roles, id: false do |t|
       t.integer :overview_id
diff --git a/db/migrate/20170420000001_chat_increase_message_size.rb b/db/migrate/20170420000001_chat_increase_message_size.rb
index 382bdfa6d..4df90947d 100644
--- a/db/migrate/20170420000001_chat_increase_message_size.rb
+++ b/db/migrate/20170420000001_chat_increase_message_size.rb
@@ -2,7 +2,7 @@ class ChatIncreaseMessageSize < ActiveRecord::Migration[4.2]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     change_column :chat_messages, :content, :text, limit: 20.megabytes + 1, null: false
   end
diff --git a/db/migrate/20170421000001_pretty_date_options_added.rb b/db/migrate/20170421000001_pretty_date_options_added.rb
index 3ed947a66..593c22b92 100644
--- a/db/migrate/20170421000001_pretty_date_options_added.rb
+++ b/db/migrate/20170421000001_pretty_date_options_added.rb
@@ -2,7 +2,7 @@ class PrettyDateOptionsAdded < ActiveRecord::Migration[4.2]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Setting.create_or_update(
       title:       'Pretty Date',
diff --git a/db/migrate/20170421110000_add_origin_by_id.rb b/db/migrate/20170421110000_add_origin_by_id.rb
index c010e9cca..520d87496 100644
--- a/db/migrate/20170421110000_add_origin_by_id.rb
+++ b/db/migrate/20170421110000_add_origin_by_id.rb
@@ -2,7 +2,7 @@ class AddOriginById < ActiveRecord::Migration[4.2]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     add_column :ticket_articles, :origin_by_id, :integer
   end
diff --git a/db/migrate/20170426135500_add_reply_to.rb b/db/migrate/20170426135500_add_reply_to.rb
index 86cfec2fb..d59db438d 100644
--- a/db/migrate/20170426135500_add_reply_to.rb
+++ b/db/migrate/20170426135500_add_reply_to.rb
@@ -2,7 +2,7 @@ class AddReplyTo < ActiveRecord::Migration[4.2]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     add_column :ticket_articles, :reply_to, :string, limit: 300
   end
diff --git a/db/migrate/20170504144100_follow_up_merged.rb b/db/migrate/20170504144100_follow_up_merged.rb
index e8056f295..3968506dc 100644
--- a/db/migrate/20170504144100_follow_up_merged.rb
+++ b/db/migrate/20170504144100_follow_up_merged.rb
@@ -2,7 +2,7 @@ class FollowUpMerged < ActiveRecord::Migration[4.2]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Setting.create_if_not_exists(
       title:       'Defines postmaster filter.',
diff --git a/db/migrate/20170515000001_scheduler_status.rb b/db/migrate/20170515000001_scheduler_status.rb
index dcaa8ef87..81f02fcb2 100644
--- a/db/migrate/20170515000001_scheduler_status.rb
+++ b/db/migrate/20170515000001_scheduler_status.rb
@@ -2,7 +2,7 @@ class SchedulerStatus < ActiveRecord::Migration[4.2]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     change_table :schedulers do |t|
       t.string :error_message, null: true
diff --git a/db/migrate/20170516000001_trigger_recipient_update.rb b/db/migrate/20170516000001_trigger_recipient_update.rb
index 2df46112b..01e33e53e 100644
--- a/db/migrate/20170516000001_trigger_recipient_update.rb
+++ b/db/migrate/20170516000001_trigger_recipient_update.rb
@@ -2,7 +2,7 @@ class TriggerRecipientUpdate < ActiveRecord::Migration[4.2]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     ['auto reply (on new tickets)', 'auto reply (on follow-up of tickets)'].each do |name|
 
diff --git a/db/migrate/20170525000001_reply_to_sender_feature.rb b/db/migrate/20170525000001_reply_to_sender_feature.rb
index 72ed3a9d1..abf26894e 100644
--- a/db/migrate/20170525000001_reply_to_sender_feature.rb
+++ b/db/migrate/20170525000001_reply_to_sender_feature.rb
@@ -2,7 +2,7 @@ class ReplyToSenderFeature < ActiveRecord::Migration[4.2]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Setting.create_if_not_exists(
       title:       'Sender based on Reply-To header',
diff --git a/db/migrate/20170529000002_setting_delivery_permanent_failed.rb b/db/migrate/20170529000002_setting_delivery_permanent_failed.rb
index dbc39dea1..29160617b 100644
--- a/db/migrate/20170529000002_setting_delivery_permanent_failed.rb
+++ b/db/migrate/20170529000002_setting_delivery_permanent_failed.rb
@@ -2,7 +2,7 @@ class SettingDeliveryPermanentFailed < ActiveRecord::Migration[4.2]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     setting = Setting.find_by(name: '0900_postmaster_filter_bounce_check')
     if setting
diff --git a/db/migrate/20170529132120_ldap_multi_group_mapping.rb b/db/migrate/20170529132120_ldap_multi_group_mapping.rb
index ae745dbee..f0d711611 100644
--- a/db/migrate/20170529132120_ldap_multi_group_mapping.rb
+++ b/db/migrate/20170529132120_ldap_multi_group_mapping.rb
@@ -2,7 +2,7 @@ class LdapMultiGroupMapping < ActiveRecord::Migration[4.2]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     # load existing LDAP config
     ldap_config = Setting.get('ldap_config')
diff --git a/db/migrate/20170531144425_foreign_keys.rb b/db/migrate/20170531144425_foreign_keys.rb
index cd124e74d..85db68367 100644
--- a/db/migrate/20170531144425_foreign_keys.rb
+++ b/db/migrate/20170531144425_foreign_keys.rb
@@ -4,7 +4,7 @@ class ForeignKeys < ActiveRecord::Migration[4.2]
   def change
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     # remove wrong plural of ID columns
     ActiveRecord::Migration.rename_column :ticket_flags, :tickets_id, :ticket_id
diff --git a/db/migrate/20170608151442_enhanced_permissions.rb b/db/migrate/20170608151442_enhanced_permissions.rb
index b47a1daeb..b3d1c83e2 100644
--- a/db/migrate/20170608151442_enhanced_permissions.rb
+++ b/db/migrate/20170608151442_enhanced_permissions.rb
@@ -2,7 +2,7 @@ class EnhancedPermissions < ActiveRecord::Migration[4.2]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     change_column_null :groups_users, :user_id, false
     change_column_null :groups_users, :group_id, false
diff --git a/db/migrate/20170619000001_tree_select.rb b/db/migrate/20170619000001_tree_select.rb
index 8416568ac..9c8ab0b32 100644
--- a/db/migrate/20170619000001_tree_select.rb
+++ b/db/migrate/20170619000001_tree_select.rb
@@ -2,7 +2,7 @@ class TreeSelect < ActiveRecord::Migration[4.2]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     change_column :object_manager_attributes, :data_option, :text, limit: 800.kilobytes + 1, null: true
     change_column :object_manager_attributes, :data_option_new, :text, limit: 800.kilobytes + 1, null: true
diff --git a/db/migrate/20170626000001_locale_add_direction.rb b/db/migrate/20170626000001_locale_add_direction.rb
index 5302ff115..36ce63991 100644
--- a/db/migrate/20170626000001_locale_add_direction.rb
+++ b/db/migrate/20170626000001_locale_add_direction.rb
@@ -2,7 +2,7 @@ class LocaleAddDirection < ActiveRecord::Migration[4.2]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     add_column :locales, :dir, :string, limit: 9, null: false, default: 'ltr'
   end
diff --git a/db/migrate/20170628000001_form_group_selection.rb b/db/migrate/20170628000001_form_group_selection.rb
index ed2e7e367..fe15467b8 100644
--- a/db/migrate/20170628000001_form_group_selection.rb
+++ b/db/migrate/20170628000001_form_group_selection.rb
@@ -2,7 +2,7 @@ class FormGroupSelection < ActiveRecord::Migration[4.2]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     group = Group.where(active: true).first
     if !group
diff --git a/db/migrate/20170629000001_exchange_integration.rb b/db/migrate/20170629000001_exchange_integration.rb
index 2d715a750..aba8bf411 100644
--- a/db/migrate/20170629000001_exchange_integration.rb
+++ b/db/migrate/20170629000001_exchange_integration.rb
@@ -2,7 +2,7 @@ class ExchangeIntegration < ActiveRecord::Migration[4.2]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Setting.set('import_backends', ['Import::Ldap', 'Import::Exchange'])
 
diff --git a/db/migrate/20170713000001_omniauth_office365_setting.rb b/db/migrate/20170713000001_omniauth_office365_setting.rb
index 553aeafd8..53e1038ff 100644
--- a/db/migrate/20170713000001_omniauth_office365_setting.rb
+++ b/db/migrate/20170713000001_omniauth_office365_setting.rb
@@ -2,7 +2,7 @@ class OmniauthOffice365Setting < ActiveRecord::Migration[4.2]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Setting.create_if_not_exists(
       title:       'Authentication via %s',
diff --git a/db/migrate/20170713000002_ticket_zoom_setting2.rb b/db/migrate/20170713000002_ticket_zoom_setting2.rb
index ec397a5d8..b7355ea57 100644
--- a/db/migrate/20170713000002_ticket_zoom_setting2.rb
+++ b/db/migrate/20170713000002_ticket_zoom_setting2.rb
@@ -2,7 +2,7 @@ class TicketZoomSetting2 < ActiveRecord::Migration[4.2]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     setting = Setting.find_by(name: 'ui_ticket_zoom_article_new_internal')
     if setting
diff --git a/db/migrate/20170714000001_object_manager_user_email_optional.rb b/db/migrate/20170714000001_object_manager_user_email_optional.rb
index 7733b2c25..0a3c53c5e 100644
--- a/db/migrate/20170714000001_object_manager_user_email_optional.rb
+++ b/db/migrate/20170714000001_object_manager_user_email_optional.rb
@@ -2,7 +2,7 @@ class ObjectManagerUserEmailOptional < ActiveRecord::Migration[4.2]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     ObjectManager::Attribute.add(
       force:       true,
diff --git a/db/migrate/20170714000002_user_email_multiple_use.rb b/db/migrate/20170714000002_user_email_multiple_use.rb
index da0323db0..69f0f4c1f 100644
--- a/db/migrate/20170714000002_user_email_multiple_use.rb
+++ b/db/migrate/20170714000002_user_email_multiple_use.rb
@@ -2,7 +2,7 @@ class UserEmailMultipleUse < ActiveRecord::Migration[4.2]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Setting.create_if_not_exists(
       title:       'User email for muliple users',
diff --git a/db/migrate/20170714000003_cleanup_cti_log.rb b/db/migrate/20170714000003_cleanup_cti_log.rb
index 726c4463b..fb790b3cc 100644
--- a/db/migrate/20170714000003_cleanup_cti_log.rb
+++ b/db/migrate/20170714000003_cleanup_cti_log.rb
@@ -2,7 +2,7 @@ class CleanupCtiLog < ActiveRecord::Migration[4.2]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Scheduler.create_if_not_exists(
       name:          'Cleanup Cti::Log',
diff --git a/db/migrate/20170727000001_setting_proxy.rb b/db/migrate/20170727000001_setting_proxy.rb
index 328951274..0874d1a28 100644
--- a/db/migrate/20170727000001_setting_proxy.rb
+++ b/db/migrate/20170727000001_setting_proxy.rb
@@ -2,7 +2,7 @@ class SettingProxy < ActiveRecord::Migration[4.2]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Setting.create_if_not_exists(
       title:       'Proxy Settings',
diff --git a/db/migrate/20170816000001_idoit_support.rb b/db/migrate/20170816000001_idoit_support.rb
index 66b6bc48e..41cb2a732 100644
--- a/db/migrate/20170816000001_idoit_support.rb
+++ b/db/migrate/20170816000001_idoit_support.rb
@@ -2,7 +2,7 @@ class IdoitSupport < ActiveRecord::Migration[4.2]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Setting.create_if_not_exists(
       title:       'i-doit integration',
diff --git a/db/migrate/20170822000001_agend_based_sender_issue_1351.rb b/db/migrate/20170822000001_agend_based_sender_issue_1351.rb
index 784ccdd2b..c57e39dec 100644
--- a/db/migrate/20170822000001_agend_based_sender_issue_1351.rb
+++ b/db/migrate/20170822000001_agend_based_sender_issue_1351.rb
@@ -2,7 +2,7 @@ class AgendBasedSenderIssue1351 < ActiveRecord::Migration[4.2]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     EmailAddress.all.each do |email_address|
 
diff --git a/db/migrate/20170910000002_out_of_office2.rb b/db/migrate/20170910000002_out_of_office2.rb
index 0796c3479..4f5a3ef67 100644
--- a/db/migrate/20170910000002_out_of_office2.rb
+++ b/db/migrate/20170910000002_out_of_office2.rb
@@ -2,7 +2,7 @@ class OutOfOffice2 < ActiveRecord::Migration[4.2]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     if !ActiveRecord::Base.connection.column_exists?(:overviews, :out_of_office)
       add_column :overviews, :out_of_office, :boolean, null: false, default: false
diff --git a/db/migrate/20170924054554_weibo_oauth2.rb b/db/migrate/20170924054554_weibo_oauth2.rb
index 02ecad20f..af71d06c1 100644
--- a/db/migrate/20170924054554_weibo_oauth2.rb
+++ b/db/migrate/20170924054554_weibo_oauth2.rb
@@ -2,7 +2,7 @@ class WeiboOauth2 < ActiveRecord::Migration[4.2]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Setting.create_if_not_exists(
       title:       'Authentication via %s',
diff --git a/db/migrate/20170927000001_setting_send_no_auto_response_reg_exp.rb b/db/migrate/20170927000001_setting_send_no_auto_response_reg_exp.rb
index a4d280ca9..5f6c59604 100644
--- a/db/migrate/20170927000001_setting_send_no_auto_response_reg_exp.rb
+++ b/db/migrate/20170927000001_setting_send_no_auto_response_reg_exp.rb
@@ -2,10 +2,10 @@ class SettingSendNoAutoResponseRegExp < ActiveRecord::Migration[5.0]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     # improved domain name matching
-    return if !Setting.find_by(name: 'send_no_auto_response_reg_exp')
+    return if !Setting.exists?(name: 'send_no_auto_response_reg_exp')
 
     Setting.set('send_no_auto_response_reg_exp', '(mailer-daemon|postmaster|abuse|root|noreply|noreply.+?|no-reply|no-reply.+?)@.+?')
   end
diff --git a/db/migrate/20171002091043_change_note_char_limit_for_users_and_organizations.rb b/db/migrate/20171002091043_change_note_char_limit_for_users_and_organizations.rb
index 91d64f89b..a1e37143f 100644
--- a/db/migrate/20171002091043_change_note_char_limit_for_users_and_organizations.rb
+++ b/db/migrate/20171002091043_change_note_char_limit_for_users_and_organizations.rb
@@ -1,7 +1,7 @@
 class ChangeNoteCharLimitForUsersAndOrganizations < ActiveRecord::Migration[5.1]
   def up
     # return if it's a new setup to avoid running the migration
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     change_column :organizations, :note, :string, limit: 5000
     change_column :users, :note, :string, limit: 5000
diff --git a/db/migrate/20171023000001_fixed_store_upgrade_ror_45.rb b/db/migrate/20171023000001_fixed_store_upgrade_ror_45.rb
index e41354055..83212d37d 100644
--- a/db/migrate/20171023000001_fixed_store_upgrade_ror_45.rb
+++ b/db/migrate/20171023000001_fixed_store_upgrade_ror_45.rb
@@ -2,7 +2,7 @@ class FixedStoreUpgradeRor45 < ActiveRecord::Migration[5.0]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Cache.clear
     [Macro, Taskbar, Calendar, Trigger, Channel, Job, PostmasterFilter, Report::Profile, Setting, Sla, Template].each do |class_name|
diff --git a/db/migrate/20171024000001_monit_integration.rb b/db/migrate/20171024000001_monit_integration.rb
index 56d22522a..ae9dbfed0 100644
--- a/db/migrate/20171024000001_monit_integration.rb
+++ b/db/migrate/20171024000001_monit_integration.rb
@@ -2,7 +2,7 @@ class MonitIntegration < ActiveRecord::Migration[4.2]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Setting.create_if_not_exists(
       title:       'Monit integration',
diff --git a/db/migrate/20171024000002_check_mk_integration2.rb b/db/migrate/20171024000002_check_mk_integration2.rb
index a8ad18669..fb8e2b01b 100644
--- a/db/migrate/20171024000002_check_mk_integration2.rb
+++ b/db/migrate/20171024000002_check_mk_integration2.rb
@@ -2,7 +2,7 @@ class CheckMkIntegration2 < ActiveRecord::Migration[4.2]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Setting.create_if_not_exists(
       title:       'Check_MK integration',
diff --git a/db/migrate/20171102000001_last_owner_update2.rb b/db/migrate/20171102000001_last_owner_update2.rb
index a0d402c17..968b54184 100644
--- a/db/migrate/20171102000001_last_owner_update2.rb
+++ b/db/migrate/20171102000001_last_owner_update2.rb
@@ -2,7 +2,7 @@ class LastOwnerUpdate2 < ActiveRecord::Migration[5.1]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     # reset assignment_timeout to prevent unwanted things happen
     Group.all.each do |group|
diff --git a/db/migrate/20171123000001_email_process_customer_selection_based_on_sender_recipient.rb b/db/migrate/20171123000001_email_process_customer_selection_based_on_sender_recipient.rb
index 89010f620..9d74a0cb5 100644
--- a/db/migrate/20171123000001_email_process_customer_selection_based_on_sender_recipient.rb
+++ b/db/migrate/20171123000001_email_process_customer_selection_based_on_sender_recipient.rb
@@ -2,7 +2,7 @@ class EmailProcessCustomerSelectionBasedOnSenderRecipient < ActiveRecord::Migrat
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Setting.create_if_not_exists(
       title:       'Customer selection based on sender and receiver list',
diff --git a/db/migrate/20171203000001_setting_es_pipeline.rb b/db/migrate/20171203000001_setting_es_pipeline.rb
index ab4813f2a..ec774098b 100644
--- a/db/migrate/20171203000001_setting_es_pipeline.rb
+++ b/db/migrate/20171203000001_setting_es_pipeline.rb
@@ -2,7 +2,7 @@ class SettingEsPipeline < ActiveRecord::Migration[5.1]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Setting.create_if_not_exists(
       title:       'Elasticsearch Pipeline Name',
diff --git a/db/migrate/20171206000001_setting_default_locale2.rb b/db/migrate/20171206000001_setting_default_locale2.rb
index 6892b6973..b0e850cfe 100644
--- a/db/migrate/20171206000001_setting_default_locale2.rb
+++ b/db/migrate/20171206000001_setting_default_locale2.rb
@@ -2,7 +2,7 @@ class SettingDefaultLocale2 < ActiveRecord::Migration[5.1]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     setting = Setting.find_by(name: 'locale_default')
     if setting
diff --git a/db/migrate/20171207000001_permission_user_preferences_out_of_office.rb b/db/migrate/20171207000001_permission_user_preferences_out_of_office.rb
index 75b81087a..d5a10268d 100644
--- a/db/migrate/20171207000001_permission_user_preferences_out_of_office.rb
+++ b/db/migrate/20171207000001_permission_user_preferences_out_of_office.rb
@@ -2,7 +2,7 @@ class PermissionUserPreferencesOutOfOffice < ActiveRecord::Migration[5.1]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Permission.create_if_not_exists(
       name:        'user_preferences.out_of_office',
diff --git a/db/migrate/20171213000001_change_authorization_token_size.rb b/db/migrate/20171213000001_change_authorization_token_size.rb
index 34a71e23f..8596792cb 100644
--- a/db/migrate/20171213000001_change_authorization_token_size.rb
+++ b/db/migrate/20171213000001_change_authorization_token_size.rb
@@ -1,7 +1,7 @@
 class ChangeAuthorizationTokenSize < ActiveRecord::Migration[5.1]
   def up
     # return if it's a new setup to avoid running the migration
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     change_column :authorizations, :token, :string, limit: 2500
 
diff --git a/db/migrate/20180108000001_change_exchange_external_sync_identifier.rb b/db/migrate/20180108000001_change_exchange_external_sync_identifier.rb
index 4c2de5e57..5bf4c65e6 100644
--- a/db/migrate/20180108000001_change_exchange_external_sync_identifier.rb
+++ b/db/migrate/20180108000001_change_exchange_external_sync_identifier.rb
@@ -1,7 +1,7 @@
 class ChangeExchangeExternalSyncIdentifier < ActiveRecord::Migration[5.1]
   def up
     # return if it's a new setup to avoid running the migration
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     ExternalSync.where(
       source: 'EWS::FolderContact'
diff --git a/db/migrate/20180111000001_ldap_samaccountname_to_uid.rb b/db/migrate/20180111000001_ldap_samaccountname_to_uid.rb
index 6a79d14b3..92d8dcc46 100644
--- a/db/migrate/20180111000001_ldap_samaccountname_to_uid.rb
+++ b/db/migrate/20180111000001_ldap_samaccountname_to_uid.rb
@@ -2,7 +2,7 @@ class LdapSamaccountnameToUid < ActiveRecord::Migration[5.1]
 
   def up
     # return if it's a new setup to avoid running the migration
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Delayed::Job.enqueue MigrationJob::LdapSamaccountnameToUid.new
   end
diff --git a/db/migrate/20180116000001_setting_ticket_number_ignore_system_id_support.rb b/db/migrate/20180116000001_setting_ticket_number_ignore_system_id_support.rb
index 048f7192b..b76739e84 100644
--- a/db/migrate/20180116000001_setting_ticket_number_ignore_system_id_support.rb
+++ b/db/migrate/20180116000001_setting_ticket_number_ignore_system_id_support.rb
@@ -2,7 +2,7 @@ class SettingTicketNumberIgnoreSystemIdSupport < ActiveRecord::Migration[4.2]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Setting.create_if_not_exists(
       title:       'Ticket Number ignore system_id',
diff --git a/db/migrate/20180128000001_chat_add_ip_country.rb b/db/migrate/20180128000001_chat_add_ip_country.rb
index 7b70d32f5..980a360a6 100644
--- a/db/migrate/20180128000001_chat_add_ip_country.rb
+++ b/db/migrate/20180128000001_chat_add_ip_country.rb
@@ -2,7 +2,7 @@ class ChatAddIpCountry < ActiveRecord::Migration[5.1]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     add_column :chats, :block_ip, :string, limit: 5000, null: true
     add_column :chats, :block_country, :string, limit: 5000, null: true
diff --git a/db/migrate/20180202000001_sidebar_customer_open_ticket_colored.rb b/db/migrate/20180202000001_sidebar_customer_open_ticket_colored.rb
index 8f509451d..736c937db 100644
--- a/db/migrate/20180202000001_sidebar_customer_open_ticket_colored.rb
+++ b/db/migrate/20180202000001_sidebar_customer_open_ticket_colored.rb
@@ -2,7 +2,7 @@ class SidebarCustomerOpenTicketColored < ActiveRecord::Migration[5.1]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Setting.create_if_not_exists(
       title:       'Open ticket indicator',
diff --git a/db/migrate/20180202000002_custom_ldap_login_attribute.rb b/db/migrate/20180202000002_custom_ldap_login_attribute.rb
index 94017431e..4fdfcfbad 100644
--- a/db/migrate/20180202000002_custom_ldap_login_attribute.rb
+++ b/db/migrate/20180202000002_custom_ldap_login_attribute.rb
@@ -2,7 +2,7 @@ class CustomLdapLoginAttribute < ActiveRecord::Migration[5.1]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
     return if no_change_needed?
 
     perform_changes
diff --git a/db/migrate/20180220000001_setting_attachment_preview.rb b/db/migrate/20180220000001_setting_attachment_preview.rb
index c68580c44..6c8ed0973 100644
--- a/db/migrate/20180220000001_setting_attachment_preview.rb
+++ b/db/migrate/20180220000001_setting_attachment_preview.rb
@@ -2,7 +2,7 @@ class SettingAttachmentPreview < ActiveRecord::Migration[5.1]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Setting.create_if_not_exists(
       title:       'Sidebar Attachments',
diff --git a/db/migrate/20180220000002_setting_user_organization_selector_with_email.rb b/db/migrate/20180220000002_setting_user_organization_selector_with_email.rb
index c722ddce4..4513e89bd 100644
--- a/db/migrate/20180220000002_setting_user_organization_selector_with_email.rb
+++ b/db/migrate/20180220000002_setting_user_organization_selector_with_email.rb
@@ -2,7 +2,7 @@ class SettingUserOrganizationSelectorWithEmail < ActiveRecord::Migration[5.1]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Setting.create_if_not_exists(
       title:       'User Organization Selector - email',
diff --git a/db/migrate/20180220171219_check_for_object_attributes.rb b/db/migrate/20180220171219_check_for_object_attributes.rb
index 44767cd87..8de4127ad 100644
--- a/db/migrate/20180220171219_check_for_object_attributes.rb
+++ b/db/migrate/20180220171219_check_for_object_attributes.rb
@@ -1,6 +1,6 @@
 class CheckForObjectAttributes < ActiveRecord::Migration[5.1]
   def change
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     attributes.each do |attribute|
 
diff --git a/db/migrate/20180226085743_issue_1660_fix_tree_select_configurations.rb b/db/migrate/20180226085743_issue_1660_fix_tree_select_configurations.rb
index 0b1d42e92..8efefaa3a 100644
--- a/db/migrate/20180226085743_issue_1660_fix_tree_select_configurations.rb
+++ b/db/migrate/20180226085743_issue_1660_fix_tree_select_configurations.rb
@@ -2,7 +2,7 @@ class Issue1660FixTreeSelectConfigurations < ActiveRecord::Migration[5.1]
   def change
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     return if attributes.blank?
 
diff --git a/db/migrate/20180306084119_custom_html_email_css_font.rb b/db/migrate/20180306084119_custom_html_email_css_font.rb
index 1d7b0e6f3..cd85fc8ee 100644
--- a/db/migrate/20180306084119_custom_html_email_css_font.rb
+++ b/db/migrate/20180306084119_custom_html_email_css_font.rb
@@ -2,7 +2,7 @@ class CustomHtmlEmailCssFont < ActiveRecord::Migration[5.1]
   def change
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Setting.create_if_not_exists(
       title:       'HTML Email CSS Font',
diff --git a/db/migrate/20180320000001_setting_table_group_by_show_count.rb b/db/migrate/20180320000001_setting_table_group_by_show_count.rb
index a5a8641dc..357e57aad 100644
--- a/db/migrate/20180320000001_setting_table_group_by_show_count.rb
+++ b/db/migrate/20180320000001_setting_table_group_by_show_count.rb
@@ -2,7 +2,7 @@ class SettingTableGroupByShowCount < ActiveRecord::Migration[5.1]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Setting.create_if_not_exists(
       title:       'Open ticket indicator',
diff --git a/db/migrate/20180327170847_issue_1905_exchange_login_from_remote_id.rb b/db/migrate/20180327170847_issue_1905_exchange_login_from_remote_id.rb
index 2d78fb5cf..bc005bbfc 100644
--- a/db/migrate/20180327170847_issue_1905_exchange_login_from_remote_id.rb
+++ b/db/migrate/20180327170847_issue_1905_exchange_login_from_remote_id.rb
@@ -2,7 +2,7 @@ class Issue1905ExchangeLoginFromRemoteId < ActiveRecord::Migration[5.1]
   def change
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     config = Import::Exchange.config
     return if config.blank?
diff --git a/db/migrate/20180418000001_setting_third_party_link_account_at_login.rb b/db/migrate/20180418000001_setting_third_party_link_account_at_login.rb
index e563a4d64..64bd094f0 100644
--- a/db/migrate/20180418000001_setting_third_party_link_account_at_login.rb
+++ b/db/migrate/20180418000001_setting_third_party_link_account_at_login.rb
@@ -2,7 +2,7 @@ class SettingThirdPartyLinkAccountAtLogin < ActiveRecord::Migration[5.1]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Setting.create_if_not_exists(
       title:       'Automatic account link on initial logon',
diff --git a/db/migrate/20180426134922_issue_1977_remove_invalid_user_foreign_keys.rb b/db/migrate/20180426134922_issue_1977_remove_invalid_user_foreign_keys.rb
index ea38b65a5..ff0994f67 100644
--- a/db/migrate/20180426134922_issue_1977_remove_invalid_user_foreign_keys.rb
+++ b/db/migrate/20180426134922_issue_1977_remove_invalid_user_foreign_keys.rb
@@ -2,7 +2,7 @@ class Issue1977RemoveInvalidUserForeignKeys < ActiveRecord::Migration[5.1]
   def change
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     # cleanup
     OnlineNotification.joins('LEFT OUTER JOIN users ON online_notifications.user_id = users.id')
diff --git a/db/migrate/20180502015927_issue_1219_zhtw_locale_typo.rb b/db/migrate/20180502015927_issue_1219_zhtw_locale_typo.rb
index 04ca99524..953c3ccdf 100644
--- a/db/migrate/20180502015927_issue_1219_zhtw_locale_typo.rb
+++ b/db/migrate/20180502015927_issue_1219_zhtw_locale_typo.rb
@@ -3,7 +3,7 @@ class Issue1219ZhtwLocaleTypo < ActiveRecord::Migration[5.1]
   APPLICABLE_VERSION = Gem::Version.new('2.5.0')
 
   def up
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
     return if CURRENT_VERSION < APPLICABLE_VERSION
 
     if Locale.exists?(locale: 'zh-tw')
@@ -20,7 +20,7 @@ class Issue1219ZhtwLocaleTypo < ActiveRecord::Migration[5.1]
   end
 
   def down
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
     return if CURRENT_VERSION >= APPLICABLE_VERSION
 
     if Locale.exists?(locale: 'zj-tw')
diff --git a/db/migrate/20180508182850_ticket_create_types_setting_issue_1987.rb b/db/migrate/20180508182850_ticket_create_types_setting_issue_1987.rb
index fe2c9dec2..b7b6febb1 100644
--- a/db/migrate/20180508182850_ticket_create_types_setting_issue_1987.rb
+++ b/db/migrate/20180508182850_ticket_create_types_setting_issue_1987.rb
@@ -1,7 +1,7 @@
 class TicketCreateTypesSettingIssue1987 < ActiveRecord::Migration[5.1]
   def up
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Setting.create_if_not_exists(
       title:       'Default type for a new ticket',
diff --git a/db/migrate/20180518000001_issue2029_sipgate_integration_enable.rb b/db/migrate/20180518000001_issue2029_sipgate_integration_enable.rb
index d848c3542..ce10db4a8 100644
--- a/db/migrate/20180518000001_issue2029_sipgate_integration_enable.rb
+++ b/db/migrate/20180518000001_issue2029_sipgate_integration_enable.rb
@@ -2,7 +2,7 @@ class Issue2029SipgateIntegrationEnable < ActiveRecord::Migration[5.1]
   def change
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     return if Setting.get('sipgate_config').present?
 
diff --git a/db/migrate/20180518100316_email_forward_prefix_setting_issue_1730.rb b/db/migrate/20180518100316_email_forward_prefix_setting_issue_1730.rb
index 6be0478c6..e8f94ee12 100644
--- a/db/migrate/20180518100316_email_forward_prefix_setting_issue_1730.rb
+++ b/db/migrate/20180518100316_email_forward_prefix_setting_issue_1730.rb
@@ -1,7 +1,7 @@
 class EmailForwardPrefixSettingIssue1730 < ActiveRecord::Migration[5.1]
   def up
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Setting.create_if_not_exists(
       title:       'Ticket Subject Forward',
diff --git a/db/migrate/20180521141004_ticket_last_contact_behavior.rb b/db/migrate/20180521141004_ticket_last_contact_behavior.rb
index f9bf1c65e..a3a16683c 100644
--- a/db/migrate/20180521141004_ticket_last_contact_behavior.rb
+++ b/db/migrate/20180521141004_ticket_last_contact_behavior.rb
@@ -1,7 +1,7 @@
 class TicketLastContactBehavior < ActiveRecord::Migration[5.1]
   def up
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Setting.create_if_not_exists(
       title:       'Ticket Last Contact Behaviour',
diff --git a/db/migrate/20180524182518_sms_support.rb b/db/migrate/20180524182518_sms_support.rb
index 3857c3e94..61939f8a7 100644
--- a/db/migrate/20180524182518_sms_support.rb
+++ b/db/migrate/20180524182518_sms_support.rb
@@ -2,7 +2,7 @@ class SmsSupport < ActiveRecord::Migration[5.1]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Permission.create_if_not_exists(
       name:        'admin.channel_sms',
diff --git a/db/migrate/20180529000001_issue_2035_recursive_ticket_trigger.rb b/db/migrate/20180529000001_issue_2035_recursive_ticket_trigger.rb
index c215f8a11..3b8c230a6 100644
--- a/db/migrate/20180529000001_issue_2035_recursive_ticket_trigger.rb
+++ b/db/migrate/20180529000001_issue_2035_recursive_ticket_trigger.rb
@@ -2,7 +2,7 @@ class Issue2035RecursiveTicketTrigger < ActiveRecord::Migration[5.1]
   def change
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Setting.create_if_not_exists(
       title:       'Recursive Ticket Triggers',
diff --git a/db/migrate/20180604000001_setting_add_ticket_auto_assignment2.rb b/db/migrate/20180604000001_setting_add_ticket_auto_assignment2.rb
index 90fa0472a..1f3a5500c 100644
--- a/db/migrate/20180604000001_setting_add_ticket_auto_assignment2.rb
+++ b/db/migrate/20180604000001_setting_add_ticket_auto_assignment2.rb
@@ -2,7 +2,7 @@ class SettingAddTicketAutoAssignment2 < ActiveRecord::Migration[5.1]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Setting.create_if_not_exists(
       title:       'Auto Assigment',
diff --git a/db/migrate/20180611070839_add_ux_flow_next_up_to_macros.rb b/db/migrate/20180611070839_add_ux_flow_next_up_to_macros.rb
index 655895966..df8b8fe6b 100644
--- a/db/migrate/20180611070839_add_ux_flow_next_up_to_macros.rb
+++ b/db/migrate/20180611070839_add_ux_flow_next_up_to_macros.rb
@@ -2,7 +2,7 @@ class AddUxFlowNextUpToMacros < ActiveRecord::Migration[5.1]
   def change
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     add_column :macros, :ux_flow_next_up, :string, default: 'none', null: false
 
diff --git a/db/migrate/20180622140531_sequencer_log_level_setting.rb b/db/migrate/20180622140531_sequencer_log_level_setting.rb
index ba3dbc3da..fbaab25f1 100644
--- a/db/migrate/20180622140531_sequencer_log_level_setting.rb
+++ b/db/migrate/20180622140531_sequencer_log_level_setting.rb
@@ -2,7 +2,7 @@ class SequencerLogLevelSetting < ActiveRecord::Migration[5.1]
   def change
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Setting.create_if_not_exists(
       title:       'Sequencer log level',
diff --git a/db/migrate/20180709020509_add_group_direction_to_overviews.rb b/db/migrate/20180709020509_add_group_direction_to_overviews.rb
index fba072601..1cc2cacbf 100644
--- a/db/migrate/20180709020509_add_group_direction_to_overviews.rb
+++ b/db/migrate/20180709020509_add_group_direction_to_overviews.rb
@@ -1,7 +1,7 @@
 class AddGroupDirectionToOverviews < ActiveRecord::Migration[5.1]
   def change
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     add_column :overviews, :group_direction, :string, limit: 250, null: true
   end
diff --git a/db/migrate/20180716060129_issue_2019_fix_double_domain_links_in_trigger_emails.rb b/db/migrate/20180716060129_issue_2019_fix_double_domain_links_in_trigger_emails.rb
index 6514a0579..430651d59 100644
--- a/db/migrate/20180716060129_issue_2019_fix_double_domain_links_in_trigger_emails.rb
+++ b/db/migrate/20180716060129_issue_2019_fix_double_domain_links_in_trigger_emails.rb
@@ -2,7 +2,7 @@ class Issue2019FixDoubleDomainLinksInTriggerEmails < ActiveRecord::Migration[5.1
   DOUBLE_DOMAIN_REGEX = %r{(?<=<a href=")https?://[^"]+(?=(https?|\#{config\.http_type})://.+?".*?>)}.freeze
 
   def up
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Trigger.where('perform LIKE ?', '%notification.email: %')
            .find_each do |t|
diff --git a/db/migrate/20180806000001_fixed_twitter_ticket_article_preferences7.rb b/db/migrate/20180806000001_fixed_twitter_ticket_article_preferences7.rb
index 5f39b5796..71dad8644 100644
--- a/db/migrate/20180806000001_fixed_twitter_ticket_article_preferences7.rb
+++ b/db/migrate/20180806000001_fixed_twitter_ticket_article_preferences7.rb
@@ -2,7 +2,7 @@ class FixedTwitterTicketArticlePreferences7 < ActiveRecord::Migration[5.0]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     # find article preferences with Twitter::NullObject and replace it with nill to prevent elasticsearch index issue
     article_type_ids = Ticket::Article::Type.where(name: ['twitter status', 'twitter direct-message']).pluck(:id)
diff --git a/db/migrate/20180809000001_cti_generic_api.rb b/db/migrate/20180809000001_cti_generic_api.rb
index 0bb55aabe..3a92417f7 100644
--- a/db/migrate/20180809000001_cti_generic_api.rb
+++ b/db/migrate/20180809000001_cti_generic_api.rb
@@ -2,7 +2,7 @@ class CtiGenericApi < ActiveRecord::Migration[5.1]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Setting.create_if_not_exists(
       title:       'cti integration',
diff --git a/db/migrate/20180830000001_setting_delivery_temporary_failed.rb b/db/migrate/20180830000001_setting_delivery_temporary_failed.rb
index a9bc1dc05..900538dc5 100644
--- a/db/migrate/20180830000001_setting_delivery_temporary_failed.rb
+++ b/db/migrate/20180830000001_setting_delivery_temporary_failed.rb
@@ -2,7 +2,7 @@ class SettingDeliveryTemporaryFailed < ActiveRecord::Migration[5.1]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Setting.create_if_not_exists(
       title:       'Defines postmaster filter.',
diff --git a/db/migrate/20180911064647_issue_2140_reset_ldap_config.rb b/db/migrate/20180911064647_issue_2140_reset_ldap_config.rb
index dbc3643ae..b12b06f4e 100644
--- a/db/migrate/20180911064647_issue_2140_reset_ldap_config.rb
+++ b/db/migrate/20180911064647_issue_2140_reset_ldap_config.rb
@@ -4,7 +4,7 @@
 class Issue2140ResetLdapConfig < ActiveRecord::Migration[5.1]
   def up
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     ldap_config = Setting.get('ldap_config')
 
diff --git a/db/migrate/20180913000001_setting_add_system_bcc.rb b/db/migrate/20180913000001_setting_add_system_bcc.rb
index 11e39ed8c..7d6b8264d 100644
--- a/db/migrate/20180913000001_setting_add_system_bcc.rb
+++ b/db/migrate/20180913000001_setting_add_system_bcc.rb
@@ -2,7 +2,7 @@ class SettingAddSystemBcc < ActiveRecord::Migration[5.1]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Setting.create_if_not_exists(
       title:       'Bcc address for all outgoing emails',
diff --git a/db/migrate/20180913000002_permission_add_time_accounting.rb b/db/migrate/20180913000002_permission_add_time_accounting.rb
index 79d609480..98661a0e3 100644
--- a/db/migrate/20180913000002_permission_add_time_accounting.rb
+++ b/db/migrate/20180913000002_permission_add_time_accounting.rb
@@ -2,7 +2,7 @@ class PermissionAddTimeAccounting < ActiveRecord::Migration[5.1]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Permission.create_if_not_exists(
       name:        'admin.time_accounting',
diff --git a/db/migrate/20180919000000_setting_update_pretty_date_format.rb b/db/migrate/20180919000000_setting_update_pretty_date_format.rb
index 85b80c4d6..4b8159102 100644
--- a/db/migrate/20180919000000_setting_update_pretty_date_format.rb
+++ b/db/migrate/20180919000000_setting_update_pretty_date_format.rb
@@ -2,7 +2,7 @@ class SettingUpdatePrettyDateFormat < ActiveRecord::Migration[5.1]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     setting = Setting.find_by(name: 'pretty_date_format')
     return if !setting
diff --git a/db/migrate/20181010000000_setting_add_sipgate_alternative_fqdn.rb b/db/migrate/20181010000000_setting_add_sipgate_alternative_fqdn.rb
index 6e3a7da35..17716a5cb 100644
--- a/db/migrate/20181010000000_setting_add_sipgate_alternative_fqdn.rb
+++ b/db/migrate/20181010000000_setting_add_sipgate_alternative_fqdn.rb
@@ -2,7 +2,7 @@ class SettingAddSipgateAlternativeFqdn < ActiveRecord::Migration[5.1]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Setting.create_if_not_exists(
       title:       'sipgate.io alternative fqdn',
diff --git a/db/migrate/20181017000001_cti_generic_api2.rb b/db/migrate/20181017000001_cti_generic_api2.rb
index 9cd9975b7..036783537 100644
--- a/db/migrate/20181017000001_cti_generic_api2.rb
+++ b/db/migrate/20181017000001_cti_generic_api2.rb
@@ -2,7 +2,7 @@ class CtiGenericApi2 < ActiveRecord::Migration[5.1]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
     return if !column_exists?(:cti_logs, :initialized_at)
     return if column_exists?(:cti_logs, :initialized_at_cleanup)
 
diff --git a/db/migrate/20181023163804_add_stats_backends.rb b/db/migrate/20181023163804_add_stats_backends.rb
index b46c2da17..4086e9d7d 100644
--- a/db/migrate/20181023163804_add_stats_backends.rb
+++ b/db/migrate/20181023163804_add_stats_backends.rb
@@ -2,7 +2,7 @@ class AddStatsBackends < ActiveRecord::Migration[5.1]
 
   def up
 
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     # add the dashboard stats backend for 'Stats::TicketWaitingTime'
     Setting.create_if_not_exists(
diff --git a/db/migrate/20181030000001_setting_add_placetel1.rb b/db/migrate/20181030000001_setting_add_placetel1.rb
index d2b25d04a..592538028 100644
--- a/db/migrate/20181030000001_setting_add_placetel1.rb
+++ b/db/migrate/20181030000001_setting_add_placetel1.rb
@@ -2,7 +2,7 @@ class SettingAddPlacetel1 < ActiveRecord::Migration[5.1]
   def change
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Setting.create_if_not_exists(
       title:       'Placetel integration',
diff --git a/db/migrate/20181108123847_add_country_attribute_to_users.rb b/db/migrate/20181108123847_add_country_attribute_to_users.rb
index 479304391..fb9991932 100644
--- a/db/migrate/20181108123847_add_country_attribute_to_users.rb
+++ b/db/migrate/20181108123847_add_country_attribute_to_users.rb
@@ -4,7 +4,7 @@
 class AddCountryAttributeToUsers < ActiveRecord::Migration[5.1]
   def up
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     # return if the country attribute already exists
     current_country_attribute = ObjectManager::Attribute.find_by(object_lookup_id: ObjectLookup.by_name('User'), name: 'country')
diff --git a/db/migrate/20181120150357_issue_2345_es_attachment_max_size_in_mb_setting_lower_default.rb b/db/migrate/20181120150357_issue_2345_es_attachment_max_size_in_mb_setting_lower_default.rb
index dd7e4e91c..6df5d336f 100644
--- a/db/migrate/20181120150357_issue_2345_es_attachment_max_size_in_mb_setting_lower_default.rb
+++ b/db/migrate/20181120150357_issue_2345_es_attachment_max_size_in_mb_setting_lower_default.rb
@@ -2,7 +2,7 @@ class Issue2345EsAttachmentMaxSizeInMbSettingLowerDefault < ActiveRecord::Migrat
   def change
 
     # return if it's a new setup to avoid running the migration
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     # don't change non default/custom value
     return if Setting.get('es_attachment_max_size_in_mb') != 50
diff --git a/db/migrate/20181123000000_issue_2368_add_indices_to_histories_and_tickets.rb b/db/migrate/20181123000000_issue_2368_add_indices_to_histories_and_tickets.rb
index 8d319f92e..79cb29ca7 100644
--- a/db/migrate/20181123000000_issue_2368_add_indices_to_histories_and_tickets.rb
+++ b/db/migrate/20181123000000_issue_2368_add_indices_to_histories_and_tickets.rb
@@ -1,6 +1,6 @@
 class Issue2368AddIndicesToHistoriesAndTickets < ActiveRecord::Migration[5.1]
   def up
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     add_index :histories, :related_o_id if !index_exists?(:histories, :related_o_id)
     add_index :histories, :related_history_object_id if !index_exists?(:histories, :related_history_object_id)
diff --git a/db/migrate/20181203000000_setting_add_email_full_quote_header.rb b/db/migrate/20181203000000_setting_add_email_full_quote_header.rb
index bb32d63d2..2cef647f6 100644
--- a/db/migrate/20181203000000_setting_add_email_full_quote_header.rb
+++ b/db/migrate/20181203000000_setting_add_email_full_quote_header.rb
@@ -1,7 +1,7 @@
 class SettingAddEmailFullQuoteHeader < ActiveRecord::Migration[5.1]
   def up
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Setting.create_if_not_exists(
       title:       'Email - quote header',
diff --git a/db/migrate/20190131000001_setting_change_ticket_zoom_attachment_preview.rb b/db/migrate/20190131000001_setting_change_ticket_zoom_attachment_preview.rb
index 296db7b3f..478a6ae96 100644
--- a/db/migrate/20190131000001_setting_change_ticket_zoom_attachment_preview.rb
+++ b/db/migrate/20190131000001_setting_change_ticket_zoom_attachment_preview.rb
@@ -1,7 +1,7 @@
 class SettingChangeTicketZoomAttachmentPreview < ActiveRecord::Migration[5.1]
   def up
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Setting.create_or_update(
       title:       'Sidebar Attachments',
diff --git a/db/migrate/20190208000001_setting_timezone_default.rb b/db/migrate/20190208000001_setting_timezone_default.rb
index 564563e48..463b52fc4 100644
--- a/db/migrate/20190208000001_setting_timezone_default.rb
+++ b/db/migrate/20190208000001_setting_timezone_default.rb
@@ -1,7 +1,7 @@
 class SettingTimezoneDefault < ActiveRecord::Migration[5.1]
   def up
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Setting.create_if_not_exists(
       title:       'Timezone',
diff --git a/db/migrate/20190314084909_object_manager_attribute_date_remove_future_past.rb b/db/migrate/20190314084909_object_manager_attribute_date_remove_future_past.rb
index 8e3a4e07a..a44590fd7 100644
--- a/db/migrate/20190314084909_object_manager_attribute_date_remove_future_past.rb
+++ b/db/migrate/20190314084909_object_manager_attribute_date_remove_future_past.rb
@@ -2,7 +2,7 @@ class ObjectManagerAttributeDateRemoveFuturePast < ActiveRecord::Migration[5.1]
   def change
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     ObjectManager::Attribute.where(data_type: 'date').each do |attribute|
       attribute.data_option = attribute.data_option.except(:future, :past)
diff --git a/db/migrate/20190328000000_rename_locale_on_users.rb b/db/migrate/20190328000000_rename_locale_on_users.rb
index af3e3e7cb..74deaeb08 100644
--- a/db/migrate/20190328000000_rename_locale_on_users.rb
+++ b/db/migrate/20190328000000_rename_locale_on_users.rb
@@ -1,6 +1,6 @@
 class RenameLocaleOnUsers < ActiveRecord::Migration[5.1]
   def up
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
     return if ActiveRecord::Base.connection.columns('users').map(&:name).exclude?('locale')
 
     ActiveRecord::Migration.rename_column(:users, :locale, :_locale)
diff --git a/db/migrate/20190405000001_database_indexes.rb b/db/migrate/20190405000001_database_indexes.rb
index ed212a3ed..3c77f421d 100644
--- a/db/migrate/20190405000001_database_indexes.rb
+++ b/db/migrate/20190405000001_database_indexes.rb
@@ -2,7 +2,7 @@ class DatabaseIndexes < ActiveRecord::Migration[5.1]
   def change
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     map = {
       activity_streams: [
diff --git a/db/migrate/20190408000001_issue_2541_fix_notification_email_without_body.rb b/db/migrate/20190408000001_issue_2541_fix_notification_email_without_body.rb
index 1cd2edc41..642d2aae9 100644
--- a/db/migrate/20190408000001_issue_2541_fix_notification_email_without_body.rb
+++ b/db/migrate/20190408000001_issue_2541_fix_notification_email_without_body.rb
@@ -2,7 +2,7 @@ class Issue2541FixNotificationEmailWithoutBody < ActiveRecord::Migration[5.1]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     # there might be Job/Trigger selectors referencing the current user
     # that get e.g. validated in callbacks
diff --git a/db/migrate/20190415000001_setting_es_multi_index.rb b/db/migrate/20190415000001_setting_es_multi_index.rb
index 9ae3c2554..7bb6a2807 100644
--- a/db/migrate/20190415000001_setting_es_multi_index.rb
+++ b/db/migrate/20190415000001_setting_es_multi_index.rb
@@ -2,7 +2,7 @@ class SettingEsMultiIndex < ActiveRecord::Migration[5.1]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Setting.create_if_not_exists(
       title:       'Elasticsearch Multi Index',
diff --git a/db/migrate/20190418000000_normalize_setting_ticket_number_ignore_system_id.rb b/db/migrate/20190418000000_normalize_setting_ticket_number_ignore_system_id.rb
index 85c805422..912ea1ba6 100644
--- a/db/migrate/20190418000000_normalize_setting_ticket_number_ignore_system_id.rb
+++ b/db/migrate/20190418000000_normalize_setting_ticket_number_ignore_system_id.rb
@@ -1,6 +1,6 @@
 class NormalizeSettingTicketNumberIgnoreSystemId < ActiveRecord::Migration[5.1]
   def up
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
     return if !Setting.exists?(name: 'ticket_number_ignore_system_id')
 
     Setting.find_by(name: 'ticket_number_ignore_system_id')
diff --git a/db/migrate/20190531180304_initialize_knowledge_base.rb b/db/migrate/20190531180304_initialize_knowledge_base.rb
index d0b6bd26d..e4bacc129 100644
--- a/db/migrate/20190531180304_initialize_knowledge_base.rb
+++ b/db/migrate/20190531180304_initialize_knowledge_base.rb
@@ -142,7 +142,7 @@ class InitializeKnowledgeBase < ActiveRecord::Migration[5.0]
       frontend:    true
     )
 
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Permission.create_if_not_exists(
       name:        'admin.knowledge_base',
diff --git a/db/migrate/20190626000001_setting_update_karma_level.rb b/db/migrate/20190626000001_setting_update_karma_level.rb
index c27987262..8a0fc9228 100644
--- a/db/migrate/20190626000001_setting_update_karma_level.rb
+++ b/db/migrate/20190626000001_setting_update_karma_level.rb
@@ -2,7 +2,7 @@ class SettingUpdateKarmaLevel < ActiveRecord::Migration[5.1]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Setting.set(
       'karma_levels',
diff --git a/db/migrate/20190715141227_saml_auth.rb b/db/migrate/20190715141227_saml_auth.rb
index 6314a46a1..acca2fd19 100644
--- a/db/migrate/20190715141227_saml_auth.rb
+++ b/db/migrate/20190715141227_saml_auth.rb
@@ -1,7 +1,7 @@
 class SamlAuth < ActiveRecord::Migration[5.2]
   def up
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Setting.create_if_not_exists(
       title:       'Authentication via %s',
diff --git a/db/migrate/20190717210244_issue_2641_kb_color_change_limit.rb b/db/migrate/20190717210244_issue_2641_kb_color_change_limit.rb
index 76fbf9c3f..4ea4233b3 100644
--- a/db/migrate/20190717210244_issue_2641_kb_color_change_limit.rb
+++ b/db/migrate/20190717210244_issue_2641_kb_color_change_limit.rb
@@ -1,6 +1,6 @@
 class Issue2641KbColorChangeLimit < ActiveRecord::Migration[5.2]
   def change
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     change_column :knowledge_bases, :color_highlight, :string, limit: 25
     change_column :knowledge_bases, :color_header,    :string, limit: 25
diff --git a/db/migrate/20190718140450_forget_insecure_sessions.rb b/db/migrate/20190718140450_forget_insecure_sessions.rb
index 14540120f..ffe55f159 100644
--- a/db/migrate/20190718140450_forget_insecure_sessions.rb
+++ b/db/migrate/20190718140450_forget_insecure_sessions.rb
@@ -4,7 +4,7 @@
 # because those are incompatible with secure cookies anyway.
 class ForgetInsecureSessions < ActiveRecord::Migration[5.2]
   def up
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
     return if Setting.get('http_type') != 'https'
 
     ActiveRecord::SessionStore::Session.destroy_all
diff --git a/db/migrate/20190724000001_rename_reserved_words.rb b/db/migrate/20190724000001_rename_reserved_words.rb
index 865097eaa..d62a6d0dd 100644
--- a/db/migrate/20190724000001_rename_reserved_words.rb
+++ b/db/migrate/20190724000001_rename_reserved_words.rb
@@ -1,6 +1,6 @@
 class RenameReservedWords < ActiveRecord::Migration[5.1]
   def up
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     models = ObjectManager.list_objects.map(&:underscore).map { |object| object.tr('_', '/') }.map(&:classify).map(&:constantize)
 
diff --git a/db/migrate/20190806000001_setting_postmaster_send_reject_email.rb b/db/migrate/20190806000001_setting_postmaster_send_reject_email.rb
index 6c1ea1975..e76f63c1d 100644
--- a/db/migrate/20190806000001_setting_postmaster_send_reject_email.rb
+++ b/db/migrate/20190806000001_setting_postmaster_send_reject_email.rb
@@ -2,7 +2,7 @@ class SettingPostmasterSendRejectEmail < ActiveRecord::Migration[5.2]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Setting.create_if_not_exists(
       title:       'Send postmaster mail if mail too large',
diff --git a/db/migrate/20190814000001_object_manager_attribute_ticket_article_body_maxlength_change.rb b/db/migrate/20190814000001_object_manager_attribute_ticket_article_body_maxlength_change.rb
index bf22ba4bf..a9253b57c 100644
--- a/db/migrate/20190814000001_object_manager_attribute_ticket_article_body_maxlength_change.rb
+++ b/db/migrate/20190814000001_object_manager_attribute_ticket_article_body_maxlength_change.rb
@@ -1,6 +1,6 @@
 class ObjectManagerAttributeTicketArticleBodyMaxlengthChange < ActiveRecord::Migration[5.1]
   def up
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     attribute = ObjectManager::Attribute.get(
       object: 'TicketArticle',
diff --git a/db/migrate/20190903165443_issue_2595_gitlab_placeholder.rb b/db/migrate/20190903165443_issue_2595_gitlab_placeholder.rb
index c7e3467db..fbba634a2 100644
--- a/db/migrate/20190903165443_issue_2595_gitlab_placeholder.rb
+++ b/db/migrate/20190903165443_issue_2595_gitlab_placeholder.rb
@@ -1,7 +1,7 @@
 class Issue2595GitlabPlaceholder < ActiveRecord::Migration[5.2]
   def change
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     setting = Setting.find_by(name: 'auth_gitlab_credentials')
     setting.options['form'].last['placeholder'] = 'https://gitlab.YOURDOMAIN.com/api/v4/'
diff --git a/db/migrate/20190918114553_issue_2867_footer_header_public_link.rb b/db/migrate/20190918114553_issue_2867_footer_header_public_link.rb
index 78749ed4c..c800bfc3f 100644
--- a/db/migrate/20190918114553_issue_2867_footer_header_public_link.rb
+++ b/db/migrate/20190918114553_issue_2867_footer_header_public_link.rb
@@ -1,7 +1,7 @@
 class Issue2867FooterHeaderPublicLink < ActiveRecord::Migration[5.2]
   def up
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     add_column            :knowledge_base_menu_items, :location, :string, null: false, default: 'header'
     add_index             :knowledge_base_menu_items, :location
diff --git a/db/migrate/20191001090809_create_active_job_locks.rb b/db/migrate/20191001090809_create_active_job_locks.rb
index a099d243e..9dd0f12bb 100644
--- a/db/migrate/20191001090809_create_active_job_locks.rb
+++ b/db/migrate/20191001090809_create_active_job_locks.rb
@@ -1,7 +1,7 @@
 class CreateActiveJobLocks < ActiveRecord::Migration[5.2]
   def change
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     create_table :active_job_locks do |t|
       t.string :lock_key
diff --git a/db/migrate/20191029101733_issue_2608_missing_trigger_permission.rb b/db/migrate/20191029101733_issue_2608_missing_trigger_permission.rb
index d29aeb663..048736f2a 100644
--- a/db/migrate/20191029101733_issue_2608_missing_trigger_permission.rb
+++ b/db/migrate/20191029101733_issue_2608_missing_trigger_permission.rb
@@ -1,6 +1,6 @@
 class Issue2608MissingTriggerPermission < ActiveRecord::Migration[5.2]
   def up
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Permission.create_if_not_exists(
       name:        'admin.trigger',
diff --git a/db/migrate/20191107050249_issue_2460_fix_corrupted_twitter_ids.rb b/db/migrate/20191107050249_issue_2460_fix_corrupted_twitter_ids.rb
index 7ee6fc536..36dc9263c 100644
--- a/db/migrate/20191107050249_issue_2460_fix_corrupted_twitter_ids.rb
+++ b/db/migrate/20191107050249_issue_2460_fix_corrupted_twitter_ids.rb
@@ -1,6 +1,6 @@
 class Issue2460FixCorruptedTwitterIds < ActiveRecord::Migration[5.2]
   def up
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Channel.where(area: 'Twitter::Account').each do |channel|
 
diff --git a/db/migrate/20191107181428_issue_2715_fix_broken_twitter_urls.rb b/db/migrate/20191107181428_issue_2715_fix_broken_twitter_urls.rb
index 124b5b199..d1db7a818 100644
--- a/db/migrate/20191107181428_issue_2715_fix_broken_twitter_urls.rb
+++ b/db/migrate/20191107181428_issue_2715_fix_broken_twitter_urls.rb
@@ -2,7 +2,7 @@ require_dependency 'issue_2715_fix_broken_twitter_urls_job' # Rails autoloading
 
 class Issue2715FixBrokenTwitterUrls < ActiveRecord::Migration[5.2]
   def up
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Issue2715FixBrokenTwitterUrlsJob.perform_later
   end
diff --git a/db/migrate/20191129102720_active_job_lock_cleanup_job_scheduler.rb b/db/migrate/20191129102720_active_job_lock_cleanup_job_scheduler.rb
index 2f4f58722..830ef6884 100644
--- a/db/migrate/20191129102720_active_job_lock_cleanup_job_scheduler.rb
+++ b/db/migrate/20191129102720_active_job_lock_cleanup_job_scheduler.rb
@@ -1,6 +1,6 @@
 class ActiveJobLockCleanupJobScheduler < ActiveRecord::Migration[5.2]
   def up
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Scheduler.create_or_update(
       name:          'Cleanup ActiveJob locks.',
diff --git a/db/migrate/20200121000001_smime_support.rb b/db/migrate/20200121000001_smime_support.rb
index a2a427b57..c7c385565 100644
--- a/db/migrate/20200121000001_smime_support.rb
+++ b/db/migrate/20200121000001_smime_support.rb
@@ -2,7 +2,7 @@ class SMIMESupport < ActiveRecord::Migration[5.2]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Setting.create_if_not_exists(
       title:       'S/MIME integration',
diff --git a/db/migrate/20200205000001_chat_add_allow_website.rb b/db/migrate/20200205000001_chat_add_allow_website.rb
index d75a15ba8..77e496bc2 100644
--- a/db/migrate/20200205000001_chat_add_allow_website.rb
+++ b/db/migrate/20200205000001_chat_add_allow_website.rb
@@ -2,7 +2,7 @@ class ChatAddAllowWebsite < ActiveRecord::Migration[5.1]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     add_column :chats, :whitelisted_websites, :string, limit: 5000, null: true
   end
diff --git a/db/migrate/20200401000001_service_now_config.rb b/db/migrate/20200401000001_service_now_config.rb
index 4a120dbde..a9687de54 100644
--- a/db/migrate/20200401000001_service_now_config.rb
+++ b/db/migrate/20200401000001_service_now_config.rb
@@ -2,7 +2,7 @@ class ServiceNowConfig < ActiveRecord::Migration[4.2]
   def up
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Setting.create_if_not_exists(
       title:       'Defines postmaster filter.',
diff --git a/db/migrate/20200419204445_setting_websocket_backend.rb b/db/migrate/20200419204445_setting_websocket_backend.rb
index 665ff66bf..903c8feec 100644
--- a/db/migrate/20200419204445_setting_websocket_backend.rb
+++ b/db/migrate/20200419204445_setting_websocket_backend.rb
@@ -1,7 +1,7 @@
 class SettingWebsocketBackend < ActiveRecord::Migration[5.2]
   def change
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Setting.create_if_not_exists(
       title:       'Websocket backend',
diff --git a/db/migrate/20200507095900_imap_authentication_migration_cleanup_job_scheduler.rb b/db/migrate/20200507095900_imap_authentication_migration_cleanup_job_scheduler.rb
index 01c234ea4..2660df7e0 100644
--- a/db/migrate/20200507095900_imap_authentication_migration_cleanup_job_scheduler.rb
+++ b/db/migrate/20200507095900_imap_authentication_migration_cleanup_job_scheduler.rb
@@ -2,7 +2,7 @@ class ImapAuthenticationMigrationCleanupJobScheduler < ActiveRecord::Migration[5
   def change
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Scheduler.create_or_update(
       name:          'Delete obsolete classic IMAP backup.',
diff --git a/db/migrate/20200709091905_maintenance_checkmk_wordings_on_settings.rb b/db/migrate/20200709091905_maintenance_checkmk_wordings_on_settings.rb
index c2f5155ee..f423664ab 100644
--- a/db/migrate/20200709091905_maintenance_checkmk_wordings_on_settings.rb
+++ b/db/migrate/20200709091905_maintenance_checkmk_wordings_on_settings.rb
@@ -2,7 +2,7 @@ class MaintenanceCheckmkWordingsOnSettings < ActiveRecord::Migration[5.2]
   def change
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     Setting.find_by(name: 'check_mk_integration').update!(
       title:       'Checkmk integration',
diff --git a/db/migrate/20200709094556_issue_3110_service_now_provider.rb b/db/migrate/20200709094556_issue_3110_service_now_provider.rb
index cf52b3066..0ad0c53de 100644
--- a/db/migrate/20200709094556_issue_3110_service_now_provider.rb
+++ b/db/migrate/20200709094556_issue_3110_service_now_provider.rb
@@ -2,7 +2,7 @@ class Issue3110ServiceNowProvider < ActiveRecord::Migration[5.2]
   def change
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     ExternalSync.where(source: 'ServiceNow').find_each do |row|
       article = Ticket.find(row.o_id).articles.first
diff --git a/db/migrate/20200716124141_issue_3123_external_sync_ticket_merge.rb b/db/migrate/20200716124141_issue_3123_external_sync_ticket_merge.rb
index 53c631228..7d762188b 100644
--- a/db/migrate/20200716124141_issue_3123_external_sync_ticket_merge.rb
+++ b/db/migrate/20200716124141_issue_3123_external_sync_ticket_merge.rb
@@ -2,7 +2,7 @@ class Issue3123ExternalSyncTicketMerge < ActiveRecord::Migration[5.2]
   def change
 
     # return if it's a new setup
-    return if !Setting.find_by(name: 'system_init_done')
+    return if !Setting.exists?(name: 'system_init_done')
 
     merged_ticket_ids_with_external_sync.each do |id_from|
       id_to = merged_ticket_ids_map[id_from]
diff --git a/lib/app_version.rb b/lib/app_version.rb
index 3bc0a647f..3db20ed7c 100644
--- a/lib/app_version.rb
+++ b/lib/app_version.rb
@@ -34,7 +34,7 @@ send also reload type to clients
 =end
 
   def self.set(reload_required = false, type = 'app_version')
-    return false if !Setting.find_by(name: 'app_version')
+    return false if !Setting.exists?(name: 'app_version')
 
     version = "#{Time.zone.now.strftime('%Y%m%d%H%M%S')}:#{reload_required}"
     Setting.set('app_version', version)
diff --git a/lib/facebook.rb b/lib/facebook.rb
index 7ac187d1f..a2cbe505d 100644
--- a/lib/facebook.rb
+++ b/lib/facebook.rb
@@ -271,7 +271,7 @@ result
     end
 
     articles.each do |article|
-      next if Ticket::Article.find_by(message_id: article[:message_id])
+      next if Ticket::Article.exists?(message_id: article[:message_id])
 
       # set ticket state to open if not new
       ticket_state = get_state(page, post, ticket)
diff --git a/lib/import/otrs/history.rb b/lib/import/otrs/history.rb
index a95712925..8c7d10d2c 100644
--- a/lib/import/otrs/history.rb
+++ b/lib/import/otrs/history.rb
@@ -41,7 +41,7 @@ module Import
         # we perform further import
         # otherwise the following import logic (add) will
         # try to add the history attribute, too
-        sleep 1 until ::History::Attribute.find_by(name: name)
+        sleep 1 until ::History::Attribute.exists?(name: name)
         true
       end
     end
diff --git a/lib/telegram.rb b/lib/telegram.rb
index 4221ab045..c256870db 100644
--- a/lib/telegram.rb
+++ b/lib/telegram.rb
@@ -705,7 +705,7 @@ returns
 
     # prevent multiple update
     if !params[:edited_message]
-      return if Ticket::Article.find_by(message_id: Telegram.message_id(params))
+      return if Ticket::Article.exists?(message_id: Telegram.message_id(params))
     end
 
     # update article
diff --git a/lib/twitter_sync.rb b/lib/twitter_sync.rb
index f3d0885c7..e99bccc43 100644
--- a/lib/twitter_sync.rb
+++ b/lib/twitter_sync.rb
@@ -693,7 +693,7 @@ process webhook messages from twitter
       @payload['direct_message_events'].each do |item|
         next if item['type'] != 'message_create'
 
-        next if Ticket::Article.find_by(message_id: item['id'])
+        next if Ticket::Article.exists?(message_id: item['id'])
 
         user = to_user_webhook(item['message_create']['sender_id'])
         ticket = to_ticket(item, user, channel.options[:sync][:direct_messages][:group_id], channel)
@@ -703,7 +703,7 @@ process webhook messages from twitter
 
     if @payload['tweet_create_events'].present?
       @payload['tweet_create_events'].each do |item|
-        next if Ticket::Article.find_by(message_id: item['id'])
+        next if Ticket::Article.exists?(message_id: item['id'])
 
         # check if it's mention
         group_id = nil
diff --git a/spec/lib/import/otrs/history_examples.rb b/spec/lib/import/otrs/history_examples.rb
index 1f988d559..23e4ed4af 100644
--- a/spec/lib/import/otrs/history_examples.rb
+++ b/spec/lib/import/otrs/history_examples.rb
@@ -13,7 +13,7 @@ end
 RSpec.shared_examples 'Import::OTRS::History' do
   it 'responds to init_callback' do
     expect(::History).to receive(:add)
-    allow(::History::Attribute).to receive(:find_by).and_return(true)
+    allow(::History::Attribute).to receive(:exists?).and_return(true)
     blank_instance = described_class.new({})
     expect(blank_instance).to respond_to('init_callback')
   end
diff --git a/spec/support/system_init_done.rb b/spec/support/system_init_done.rb
index a2cf844ac..2b0da5192 100644
--- a/spec/support/system_init_done.rb
+++ b/spec/support/system_init_done.rb
@@ -1,12 +1,12 @@
 module SystemInitDoneHelper
   def system_init_done(state = true)
-    # generally allow all calls to Setting.find_by to avoid
+    # generally allow all calls to Setting.exists? to avoid
     # RSpec errors where a different Setting is accessed
-    allow(Setting).to receive(:find_by).and_call_original
+    allow(Setting).to receive(:exists?).and_call_original
 
     # just mock the Setting check for `system_init_done`
     # and return the given parameter value
-    expect(Setting).to receive(:find_by).with(name: 'system_init_done').and_return(state)
+    expect(Setting).to receive(:exists?).with(name: 'system_init_done').and_return(state)
   end
 end