Connection handling methods extracted out into separate ConnectionHandler class

- delegating methods left behind

3 files changed, 117 insertions, 105 deletions

diff --git a/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb b/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb
index 08fc61daaa..01a75365d3 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb
@@ -1,3 +1,4 @@
+require 'monitor'
 require 'set'
 
 module ActiveRecord
@@ -132,5 +133,93 @@ module ActiveRecord
           end
         end
     end
+
+    class ConnectionHandler
+      attr_reader :connection_pools_lock
+
+      def initialize
+        @connection_pools = {}
+        @connection_pools_lock = Monitor.new
+      end
+
+      def establish_connection(name, spec)
+        connection_pools_lock.synchronize do
+          @connection_pools[name] = ConnectionAdapters::ConnectionPool.new(spec)
+        end
+      end
+
+      # for internal use only and for testing
+      def active_connections #:nodoc:
+        @connection_pools.inject({}) do |hash,kv|
+          hash[kv.first] = kv.last.active_connection
+          hash.delete(kv.first) unless hash[kv.first]
+          hash
+        end
+      end
+
+      # Clears the cache which maps classes to connections.
+      def clear_active_connections!
+        @connection_pools.each_value {|pool| pool.clear_active_connections! }
+      end
+
+      # Clears the cache which maps classes
+      def clear_reloadable_connections!
+        @connection_pools.each_value {|pool| pool.clear_reloadable_connections! }
+      end
+
+      def clear_all_connections!
+        clear_cache!(@connection_pools) {|name, pool| pool.disconnect! }
+      end
+
+      # Verify active connections.
+      def verify_active_connections! #:nodoc:
+        @connection_pools.each_value {|pool| pool.verify_active_connections!}
+      end
+
+      # Locate the connection of the nearest super class. This can be an
+      # active or defined connection: if it is the latter, it will be
+      # opened and set as the active connection for the class it was defined
+      # for (not necessarily the current class).
+      def retrieve_connection(klass) #:nodoc:
+        pool = retrieve_connection_pool(klass)
+        (pool && pool.connection) or raise ConnectionNotEstablished
+      end
+
+      def retrieve_connection_pool(klass)
+        loop do
+          pool = @connection_pools[klass.name]
+          return pool if pool
+          return nil if ActiveRecord::Base == klass
+          klass = klass.superclass
+        end
+      end
+
+      # Returns true if a connection that's accessible to this class has already been opened.
+      def connected?(klass)
+        retrieve_connection_pool(klass).connected?
+      end
+
+      # Remove the connection for this class. This will close the active
+      # connection and the defined connection (if they exist). The result
+      # can be used as an argument for establish_connection, for easily
+      # re-establishing the connection.
+      def remove_connection(klass)
+        pool = @connection_pools[klass.name]
+        @connection_pools.delete_if { |key, value| value == pool }
+        pool.disconnect! if pool
+        pool.spec.config if pool
+      end
+
+      synchronize :retrieve_connection, :retrieve_connection_pool, :connected?,
+        :remove_connection, :active_connections, :clear_active_connections!,
+        :clear_reloadable_connections!, :clear_all_connections!,
+        :verify_active_connections!, :with => :connection_pools_lock
+
+      private
+        def clear_cache!(cache, &block)
+          cache.each(&block) if block_given?
+          cache.clear
+        end
+    end
   end
 end
\ No newline at end of file
diff --git a/activerecord/lib/active_record/connection_adapters/abstract/connection_specification.rb b/activerecord/lib/active_record/connection_adapters/abstract/connection_specification.rb
index ddca97c3bf..2dc3201208 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/connection_specification.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/connection_specification.rb
@@ -1,5 +1,3 @@
-require 'monitor'
-
 module ActiveRecord
   class Base
     class ConnectionSpecification #:nodoc:
@@ -9,80 +7,19 @@ module ActiveRecord
       end
     end
 
-    class NullMonitor
-      def synchronize
-        yield
-      end
-    end
-
-    cattr_accessor :connection_pools_lock, :instance_writer => false
-    @@connection_pools_lock = NullMonitor.new
-
     # Check for activity after at least +verification_timeout+ seconds.
     # Defaults to 0 (always check.)
     cattr_accessor :verification_timeout, :instance_writer => false
     @@verification_timeout = 0
 
-    # The class -> connection pool map
-    @@connection_pools = {}
-
-    class << self
-      # Turning on allow_concurrency basically switches a null mutex for a real one, so that
-      # multi-threaded access of the connection pools hash is synchronized.
-      def allow_concurrency=(flag)
-        if @@allow_concurrency != flag
-          @@allow_concurrency = flag
-          if flag
-            self.connection_pools_lock = Monitor.new
-          else
-            self.connection_pools_lock = NullMonitor.new
-          end
-        end
-      end
-
-      # for internal use only and for testing
-      def active_connections #:nodoc:
-        @@connection_pools.inject({}) do |hash,kv|
-          hash[kv.first] = kv.last.active_connection
-          hash.delete(kv.first) unless hash[kv.first]
-          hash
-        end
-      end
-
-      # Returns the connection currently associated with the class. This can
-      # also be used to "borrow" the connection to do database work unrelated
-      # to any of the specific Active Records.
-      def connection
-        retrieve_connection
-      end
-
-      # Clears the cache which maps classes to connections.
-      def clear_active_connections!
-        @@connection_pools.each_value {|pool| pool.clear_active_connections! }
-      end
-      
-      # Clears the cache which maps classes
-      def clear_reloadable_connections!
-        @@connection_pools.each_value {|pool| pool.clear_reloadable_connections! }
-      end
+    # The connection handler
+    cattr_accessor :connection_handler, :instance_writer => false
+    @@connection_handler = ConnectionAdapters::ConnectionHandler.new
 
-      def clear_all_connections!
-        clear_cache!(@@connection_pools) {|name, pool| pool.disconnect! }
-      end
-
-      # Verify active connections.
-      def verify_active_connections! #:nodoc:
-        @@connection_pools.each_value {|pool| pool.verify_active_connections!}
-      end
-
-      synchronize :active_connections, :clear_active_connections!, :clear_reloadable_connections!,
-        :clear_all_connections!, :verify_active_connections!, :with => :connection_pools_lock
-
-      private
-        def clear_cache!(cache, &block)
-          cache.each(&block) if block_given?
-          cache.clear
-        end
+    # Turning on allow_concurrency basically switches a null mutex for a real one, so that
+    # multi-threaded access of the connection pools hash is synchronized.
+    def self.allow_concurrency=(flag)
+      @@allow_concurrency = flag
     end
 
     # Returns the connection currently associated with the class. This can
@@ -126,9 +63,7 @@ module ActiveRecord
           raise AdapterNotSpecified unless defined? RAILS_ENV
           establish_connection(RAILS_ENV)
         when ConnectionSpecification
-          connection_pools_lock.synchronize do
-            @@connection_pools[name] = ConnectionAdapters::ConnectionPool.new(spec)
-          end
+          @@connection_handler.establish_connection(name, spec)
         when Symbol, String
           if configuration = configurations[spec.to_s]
             establish_connection(configuration)
@@ -161,41 +96,29 @@ module ActiveRecord
       end
     end
 
-    # Locate the connection of the nearest super class. This can be an
-    # active or defined connection: if it is the latter, it will be
-    # opened and set as the active connection for the class it was defined
-    # for (not necessarily the current class).
-    def self.retrieve_connection #:nodoc:
-      pool = retrieve_connection_pool
-      (pool && pool.connection) or raise ConnectionNotEstablished
-    end
+    class << self
+      # Returns the connection currently associated with the class. This can
+      # also be used to "borrow" the connection to do database work unrelated
+      # to any of the specific Active Records.
+      def connection
+        retrieve_connection
+      end
 
-    def self.retrieve_connection_pool
-      pool = @@connection_pools[name]
-      return pool if pool
-      return nil if ActiveRecord::Base == self
-      superclass.retrieve_connection_pool
-    end
+      def retrieve_connection
+        connection_handler.retrieve_connection(self)
+      end
 
-    # Returns true if a connection that's accessible to this class has already been opened.
-    def self.connected?
-      retrieve_connection_pool.connected?
-    end
+      def connected?
+        connection_handler.connected?(self)
+      end
 
-    # Remove the connection for this class. This will close the active
-    # connection and the defined connection (if they exist). The result
-    # can be used as an argument for establish_connection, for easily
-    # re-establishing the connection.
-    def self.remove_connection(klass=self)
-      pool = @@connection_pools[klass.name]
-      @@connection_pools.delete_if { |key, value| value == pool }
-      pool.disconnect! if pool
-      pool.spec.config if pool
-    end
+      def remove_connection(klass=self)
+        connection_handler.remove_connection(klass)
+      end
 
-    class << self
-      synchronize :retrieve_connection, :retrieve_connection_pool, :connected?,
-        :remove_connection, :with => :connection_pools_lock
+      delegate :active_connections, :clear_active_connections!,
+        :clear_reloadable_connections!, :clear_all_connections!,
+        :verify_active_connections!, :to => :connection_handler
     end
   end
 end
diff --git a/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb b/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb
index af8cfbee7a..4b78d9f2e9 100755
--- a/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb
@@ -7,8 +7,8 @@ require 'active_record/connection_adapters/abstract/schema_definitions'
 require 'active_record/connection_adapters/abstract/schema_statements'
 require 'active_record/connection_adapters/abstract/database_statements'
 require 'active_record/connection_adapters/abstract/quoting'
-require 'active_record/connection_adapters/abstract/connection_specification'
 require 'active_record/connection_adapters/abstract/connection_pool'
+require 'active_record/connection_adapters/abstract/connection_specification'
 require 'active_record/connection_adapters/abstract/query_cache'
 
 module ActiveRecord