r4664@asus: jeremy | 2006-06-19 18:55:36 -0700

 Use the #lock method to obtain a row lock on a single record. Simply reloads the record with :lock => true.


git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@4462 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

1 files changed, 0 insertions, 84 deletions

diff --git a/activerecord/lib/active_record/locking.rb b/activerecord/lib/active_record/locking.rb
deleted file mode 100644
index 9e7564ed25..0000000000
--- a/activerecord/lib/active_record/locking.rb
+++ /dev/null
@@ -1,84 +0,0 @@
-module ActiveRecord
-  module Locking
-    # Active Records support optimistic locking if the field <tt>lock_version</tt> is present.  Each update to the
-    # record increments the lock_version column and the locking facilities ensure that records instantiated twice
-    # will let the last one saved raise a StaleObjectError if the first was also updated. Example:
-    #
-    #   p1 = Person.find(1)
-    #   p2 = Person.find(1)
-    #   
-    #   p1.first_name = "Michael"
-    #   p1.save
-    #   
-    #   p2.first_name = "should fail"
-    #   p2.save # Raises a ActiveRecord::StaleObjectError
-    #
-    # You're then responsible for dealing with the conflict by rescuing the exception and either rolling back, merging,
-    # or otherwise apply the business logic needed to resolve the conflict.
-    #
-    # You must ensure that your database schema defaults the lock_version column to 0.
-    #
-    # This behavior can be turned off by setting <tt>ActiveRecord::Base.lock_optimistically = false</tt>.
-    # To override the name of the lock_version column, invoke the <tt>set_locking_column</tt> method.
-    # This method uses the same syntax as <tt>set_table_name</tt>
-    module Optimistic
-      def self.included(base) #:nodoc:
-        super
-        base.extend ClassMethods
-
-        base.cattr_accessor :lock_optimistically
-        base.lock_optimistically = true
-
-        base.alias_method_chain :update, :lock
-        class << base
-          alias_method :locking_column=, :set_locking_column
-        end
-      end
-
-      def locking_enabled? #:nodoc:
-        lock_optimistically && respond_to?(self.class.locking_column)
-      end
-
-      def update_with_lock #:nodoc:
-        return update_without_lock unless locking_enabled?
-
-        lock_col = self.class.locking_column
-        previous_value = send(lock_col)
-        send(lock_col + '=', previous_value + 1)
-
-        affected_rows = connection.update(<<-end_sql, "#{self.class.name} Update with optimistic locking")
-          UPDATE #{self.class.table_name}
-          SET #{quoted_comma_pair_list(connection, attributes_with_quotes(false))}
-          WHERE #{self.class.primary_key} = #{quote(id)} 
-          AND #{lock_col} = #{quote(previous_value)}
-        end_sql
-
-        unless affected_rows == 1
-          raise ActiveRecord::StaleObjectError, "Attempted to update a stale object"
-        end
-
-        return true
-      end
-
-      module ClassMethods
-        DEFAULT_LOCKING_COLUMN = 'lock_version'
-
-        # Set the column to use for optimistic locking. Defaults to lock_version.
-        def set_locking_column(value = nil, &block)
-          define_attr_method :locking_column, value, &block
-          value
-        end
-
-        # The version column used for optimistic locking. Defaults to lock_version.
-        def locking_column
-          reset_locking_column
-        end
-
-        # Reset the column used for optimistic locking back to the lock_version default.
-        def reset_locking_column
-          set_locking_column DEFAULT_LOCKING_COLUMN
-        end
-      end
-    end
-  end
-end