Added check for RAILS_CONNECTION_ADAPTERS on startup and only load the connection adapters specified within if its present (available in Rails through config.connection_adapters using the new config) #1958 [skae]

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@2248 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

activerecord/CHANGELOG

@@ -1,5 +1,7 @@
 *SVN*
 
+* Added check for RAILS_CONNECTION_ADAPTERS on startup and only load the connection adapters specified within if its present (available in Rails through config.connection_adapters using the new config) #1958
+
 * Fixed various problems with has_and_belongs_to_many when using customer finder_sql #2094 [Florian Weber]
 
 * Added better exception error when unknown column types are used with migrations #1814 [fbeausoleil@ftml.net]

activerecord/lib/active_record.rb

@@ -63,11 +63,12 @@ ActiveRecord::Base.class_eval do
   include ActiveRecord::Acts::NestedSet
 end
 
-require 'active_record/connection_adapters/mysql_adapter'
-require 'active_record/connection_adapters/postgresql_adapter'
-require 'active_record/connection_adapters/sqlite_adapter'
-require 'active_record/connection_adapters/sqlserver_adapter'
-require 'active_record/connection_adapters/db2_adapter'
-require 'active_record/connection_adapters/oci_adapter'
+unless defined?(RAILS_CONNECTION_ADAPTERS)
+  RAILS_CONNECTION_ADAPTERS = %w(mysql postgresql sqlite sqlserver db2 oci)
+end
 
-require 'active_record/query_cache'
+RAILS_CONNECTION_ADAPTERS.each do |adapter|
+  require "active_record/connection_adapters/#{adapter}_adapter"
+end
+
+require 'active_record/query_cache'

railties/environments/environment.rb

@@ -18,6 +18,9 @@ Rails::Initializer.run do |config|
   # (by default production uses :info, the others :debug)
   # config.log_level = :debug
 
+  # Only include the connection adapters you're actually going to use
+  # config.connection_adapters = %w( mysql sqlite )
+
   # Use the database for sessions instead of the file system
   # (create the session table with 'rake create_sessions_table')
   # config.action_controller.session_store = :active_record_store

railties/lib/initializer.rb

@@ -30,6 +30,7 @@ module Rails
     
     def process
       set_load_path
+      set_connection_adapters
 
       require_frameworks
       load_environment
@@ -56,6 +57,10 @@ module Rails
       $LOAD_PATH.uniq!
     end
     
+    def set_connection_adapters
+      RAILS_CONNECTION_ADAPTERS = configuration.connection_adapters
+    end
+    
     def require_frameworks
       configuration.frameworks.each { |framework| require(framework.to_s) }
     end
@@ -143,6 +148,7 @@ module Rails
   class Configuration
     attr_accessor :frameworks, :load_paths, :logger, :log_level, :log_path, :database_configuration_file, :view_path, :controller_paths
     attr_accessor :cache_classes, :breakpoint_server, :whiny_nils
+    attr_accessor :connection_adapters
     attr_accessor :active_record, :action_controller, :action_view, :action_mailer, :action_web_service
     
     def initialize
@@ -155,6 +161,7 @@ module Rails
       self.cache_classes                = default_cache_classes
       self.breakpoint_server            = default_breakpoint_server
       self.whiny_nils                   = default_whiny_nils
+      self.connection_adapters          = default_connection_adapters
       self.database_configuration_file  = default_database_configuration_file
 
       for framework in default_frameworks
@@ -258,5 +265,9 @@ module Rails
       def default_whiny_nils
         false
       end
+      
+      def default_connection_adapters
+        %w(mysql postgresql sqlite sqlserver db2 oci)
+      end
   end
 end