diff options
Diffstat (limited to 'activerecord/lib/active_record/associations/association_proxy.rb')
| -rw-r--r-- | activerecord/lib/active_record/associations/association_proxy.rb | 295 |
1 files changed, 0 insertions, 295 deletions
diff --git a/activerecord/lib/active_record/associations/association_proxy.rb b/activerecord/lib/active_record/associations/association_proxy.rb deleted file mode 100644 index f333f4d603..0000000000 --- a/activerecord/lib/active_record/associations/association_proxy.rb +++ /dev/null @@ -1,295 +0,0 @@ -require 'active_support/core_ext/array/wrap' - -module ActiveRecord - module Associations - # = Active Record Associations - # - # This is the root class of all association proxies: - # - # AssociationProxy - # BelongsToAssociation - # HasOneAssociation - # BelongsToPolymorphicAssociation - # AssociationCollection - # HasAndBelongsToManyAssociation - # HasManyAssociation - # HasManyThroughAssociation - # HasOneThroughAssociation - # - # Association proxies in Active Record are middlemen between the object that - # holds the association, known as the <tt>@owner</tt>, and the actual associated - # object, known as the <tt>@target</tt>. The kind of association any proxy is - # about is available in <tt>@reflection</tt>. That's an instance of the class - # ActiveRecord::Reflection::AssociationReflection. - # - # For example, given - # - # class Blog < ActiveRecord::Base - # has_many :posts - # end - # - # blog = Blog.find(:first) - # - # the association proxy in <tt>blog.posts</tt> has the object in +blog+ as - # <tt>@owner</tt>, the collection of its posts as <tt>@target</tt>, and - # the <tt>@reflection</tt> object represents a <tt>:has_many</tt> macro. - # - # This class has most of the basic instance methods removed, and delegates - # unknown methods to <tt>@target</tt> via <tt>method_missing</tt>. As a - # corner case, it even removes the +class+ method and that's why you get - # - # blog.posts.class # => Array - # - # though the object behind <tt>blog.posts</tt> is not an Array, but an - # ActiveRecord::Associations::HasManyAssociation. - # - # The <tt>@target</tt> object is not \loaded until needed. For example, - # - # blog.posts.count - # - # is computed directly through SQL and does not trigger by itself the - # instantiation of the actual post records. - class AssociationProxy #:nodoc: - alias_method :proxy_respond_to?, :respond_to? - alias_method :proxy_extend, :extend - delegate :to_param, :to => :proxy_target - instance_methods.each { |m| undef_method m unless m.to_s =~ /^(?:nil\?|send|object_id|to_a)$|^__|proxy_/ } - - def initialize(owner, reflection) - @owner, @reflection = owner, reflection - @updated = false - reflection.check_validity! - Array.wrap(reflection.options[:extend]).each { |ext| proxy_extend(ext) } - reset - end - - # Returns the owner of the proxy. - def proxy_owner - @owner - end - - # Returns the reflection object that represents the association handled - # by the proxy. - def proxy_reflection - @reflection - end - - # Returns the \target of the proxy, same as +target+. - def proxy_target - @target - end - - # Does the proxy or its \target respond to +symbol+? - def respond_to?(*args) - proxy_respond_to?(*args) || (load_target && @target.respond_to?(*args)) - end - - # Forwards <tt>===</tt> explicitly to the \target because the instance method - # removal above doesn't catch it. Loads the \target if needed. - def ===(other) - load_target - other === @target - end - - # Returns the name of the table of the related class: - # - # post.comments.aliased_table_name # => "comments" - # - def aliased_table_name - @reflection.klass.table_name - end - - # Returns the SQL string that corresponds to the <tt>:conditions</tt> - # option of the macro, if given, or +nil+ otherwise. - def conditions - @conditions ||= interpolate_sql(@reflection.sanitized_conditions) if @reflection.sanitized_conditions - end - alias :sql_conditions :conditions - - # Resets the \loaded flag to +false+ and sets the \target to +nil+. - def reset - @loaded = false - @target = nil - end - - # Reloads the \target and returns +self+ on success. - def reload - reset - load_target - self unless @target.nil? - end - - # Has the \target been already \loaded? - def loaded? - @loaded - end - - # Asserts the \target has been loaded setting the \loaded flag to +true+. - def loaded - @loaded = true - end - - # Returns the target of this proxy, same as +proxy_target+. - def target - @target - end - - # Sets the target of this proxy to <tt>\target</tt>, and the \loaded flag to +true+. - def target=(target) - @target = target - loaded - end - - # Forwards the call to the target. Loads the \target if needed. - def inspect - load_target - @target.inspect - end - - def send(method, *args) - if proxy_respond_to?(method) - super - else - load_target - @target.send(method, *args) - end - end - - protected - # Does the association have a <tt>:dependent</tt> option? - def dependent? - @reflection.options[:dependent] - end - - def interpolate_sql(sql, record = nil) - @owner.send(:interpolate_sql, sql, record) - end - - # Forwards the call to the reflection class. - def sanitize_sql(sql, table_name = @reflection.klass.table_name) - @reflection.klass.send(:sanitize_sql, sql, table_name) - end - - # Assigns the ID of the owner to the corresponding foreign key in +record+. - # If the association is polymorphic the type of the owner is also set. - def set_belongs_to_association_for(record) - if @reflection.options[:as] - record["#{@reflection.options[:as]}_id"] = @owner.id unless @owner.new_record? - record["#{@reflection.options[:as]}_type"] = @owner.class.base_class.name.to_s - else - unless @owner.new_record? - primary_key = @reflection.options[:primary_key] || :id - record[@reflection.primary_key_name] = @owner.send(primary_key) - end - end - end - - # Merges into +options+ the ones coming from the reflection. - def merge_options_from_reflection!(options) - options.reverse_merge!( - :group => @reflection.options[:group], - :having => @reflection.options[:having], - :limit => @reflection.options[:limit], - :offset => @reflection.options[:offset], - :joins => @reflection.options[:joins], - :include => @reflection.options[:include], - :select => @reflection.options[:select], - :readonly => @reflection.options[:readonly] - ) - end - - # Forwards +with_scope+ to the reflection. - def with_scope(*args, &block) - @reflection.klass.send :with_scope, *args, &block - end - - private - # Forwards any missing method call to the \target. - def method_missing(method, *args) - if load_target - unless @target.respond_to?(method) - message = "undefined method `#{method.to_s}' for \"#{@target}\":#{@target.class.to_s}" - raise NoMethodError, message - end - - if block_given? - @target.send(method, *args) { |*block_args| yield(*block_args) } - else - @target.send(method, *args) - end - end - end - - # Loads the \target if needed and returns it. - # - # This method is abstract in the sense that it relies on +find_target+, - # which is expected to be provided by descendants. - # - # If the \target is already \loaded it is just returned. Thus, you can call - # +load_target+ unconditionally to get the \target. - # - # ActiveRecord::RecordNotFound is rescued within the method, and it is - # not reraised. The proxy is \reset and +nil+ is the return value. - def load_target - return nil unless defined?(@loaded) - - if !loaded? and (!@owner.new_record? || foreign_key_present) - @target = find_target - end - - @loaded = true - @target - rescue ActiveRecord::RecordNotFound - reset - end - - # Can be overwritten by associations that might have the foreign key - # available for an association without having the object itself (and - # still being a new record). Currently, only +belongs_to+ presents - # this scenario (both vanilla and polymorphic). - def foreign_key_present - false - end - - # Raises ActiveRecord::AssociationTypeMismatch unless +record+ is of - # the kind of the class of the associated objects. Meant to be used as - # a sanity check when you are about to assign an associated record. - def raise_on_type_mismatch(record) - unless record.is_a?(@reflection.klass) || record.is_a?(@reflection.class_name.constantize) - message = "#{@reflection.class_name}(##{@reflection.klass.object_id}) expected, got #{record.class}(##{record.class.object_id})" - raise ActiveRecord::AssociationTypeMismatch, message - end - end - - if RUBY_VERSION < '1.9.2' - # Array#flatten has problems with recursive arrays before Ruby 1.9.2. - # Going one level deeper solves the majority of the problems. - def flatten_deeper(array) - array.collect { |element| (element.respond_to?(:flatten) && !element.is_a?(Hash)) ? element.flatten : element }.flatten - end - else - def flatten_deeper(array) - array.flatten - end - end - - # Returns the ID of the owner, quoted if needed. - def owner_quoted_id - @owner.quoted_id - end - - def set_inverse_instance(record, instance) - return if record.nil? || !we_can_set_the_inverse_on_this?(record) - inverse_relationship = @reflection.inverse_of - unless inverse_relationship.nil? - record.send(:"set_#{inverse_relationship.name}_target", instance) - end - end - - # Override in subclasses - def we_can_set_the_inverse_on_this?(record) - false - end - end - end -end |