Add whitelist mode (#11291)

app/controllers/admin/instances_controller.rb

@@ -2,6 +2,10 @@
 
 module Admin
   class InstancesController < BaseController
+    before_action :set_domain_block, only: :show
+    before_action :set_domain_allow, only: :show
+    before_action :set_instance, only: :show
+
     def index
       authorize :instance, :index?
 
@@ -11,20 +15,38 @@ module Admin
     def show
       authorize :instance, :show?
 
-      @instance        = Instance.new(Account.by_domain_accounts.find_by(domain: params[:id]) || DomainBlock.find_by!(domain: params[:id]))
       @following_count = Follow.where(account: Account.where(domain: params[:id])).count
       @followers_count = Follow.where(target_account: Account.where(domain: params[:id])).count
       @reports_count   = Report.where(target_account: Account.where(domain: params[:id])).count
       @blocks_count    = Block.where(target_account: Account.where(domain: params[:id])).count
       @available       = DeliveryFailureTracker.available?(Account.select(:shared_inbox_url).where(domain: params[:id]).first&.shared_inbox_url)
       @media_storage   = MediaAttachment.where(account: Account.where(domain: params[:id])).sum(:file_file_size)
-      @domain_block    = DomainBlock.rule_for(params[:id])
     end
 
     private
 
+    def set_domain_block
+      @domain_block = DomainBlock.rule_for(params[:id])
+    end
+
+    def set_domain_allow
+      @domain_allow = DomainAllow.rule_for(params[:id])
+    end
+
+    def set_instance
+      resource   = Account.by_domain_accounts.find_by(domain: params[:id])
+      resource ||= @domain_block
+      resource ||= @domain_allow
+
+      if resource
+        @instance = Instance.new(resource)
+      else
+        not_found
+      end
+    end
+
     def filtered_instances
-      InstanceFilter.new(filter_params).results
+      InstanceFilter.new(whitelist_mode? ? { allowed: true } : filter_params).results
     end
 
     def paginated_instances