Use connection pool instead of actual connection to avoid having to connect to the database until necessary

lib/activerecord-import.rb

@@ -2,15 +2,15 @@ class ActiveRecord::Base
   class << self
     def establish_connection_with_activerecord_import(*args)
       establish_connection_without_activerecord_import(*args)
-      ActiveSupport.run_load_hooks(:active_record_connection_established, connection)
+      ActiveSupport.run_load_hooks(:active_record_connection_established, connection_pool)
     end
     alias_method_chain :establish_connection, :activerecord_import
   end
 end
 
-ActiveSupport.on_load(:active_record_connection_established) do |connection|
-  if !ActiveRecord.const_defined?(:Import) || !ActiveRecord::Import.respond_to?(:load_from_connection)
+ActiveSupport.on_load(:active_record_connection_established) do |connection_pool|
+  if !ActiveRecord.const_defined?(:Import) || !ActiveRecord::Import.respond_to?(:load_from_connection_pool)
     require File.join File.dirname(__FILE__),  "activerecord-import/base"
   end
-  ActiveRecord::Import.load_from_connection connection
+  ActiveRecord::Import.load_from_connection_pool connection_pool
 end

lib/activerecord-import/base.rb

@@ -12,12 +12,8 @@ module ActiveRecord::Import
   end
 
   # Loads the import functionality for the passed in ActiveRecord connection
-  def self.load_from_connection(connection)
-    import_adapter = "ActiveRecord::Import::#{connection.class.name.demodulize}::InstanceMethods"
-    unless connection.class.ancestors.map(&:name).include?(import_adapter)
-      config = connection.instance_variable_get :@config
-      require_adapter config[:adapter]
-    end
+  def self.load_from_connection_pool(connection_pool)
+    require_adapter connection_pool.spec.config[:adapter]
   end
 end