diff options
Diffstat (limited to 'activerecord/lib/active_record/nested_attributes.rb')
-rw-r--r-- | activerecord/lib/active_record/nested_attributes.rb | 246 |
1 files changed, 165 insertions, 81 deletions
diff --git a/activerecord/lib/active_record/nested_attributes.rb b/activerecord/lib/active_record/nested_attributes.rb index 4c9bd76d7c..846e1162a9 100644 --- a/activerecord/lib/active_record/nested_attributes.rb +++ b/activerecord/lib/active_record/nested_attributes.rb @@ -58,7 +58,7 @@ module ActiveRecord # It also allows you to update the avatar through the member: # # params = { member: { avatar_attributes: { id: '2', icon: 'sad' } } } - # member.update_attributes params[:member] + # member.update params[:member] # member.avatar.icon # => 'sad' # # By default you will only be able to set and update attributes on the @@ -81,6 +81,9 @@ module ActiveRecord # # Note that the model will _not_ be destroyed until the parent is saved. # + # Also note that the model will not be destroyed unless you also specify + # its id in the updated hash. + # # === One-to-many # # Consider a member that has a number of posts: @@ -90,8 +93,9 @@ module ActiveRecord # accepts_nested_attributes_for :posts # end # - # You can now set or update attributes on an associated post model through - # the attribute hash. + # You can now set or update attributes on the associated posts through + # an attribute hash for a member: include the key +:posts_attributes+ + # with an array of hashes of post attributes as a value. # # For each hash that does _not_ have an <tt>id</tt> key a new record will # be instantiated, unless the hash also contains a <tt>_destroy</tt> key @@ -110,14 +114,14 @@ module ActiveRecord # member.posts.first.title # => 'Kari, the awesome Ruby documentation browser!' # member.posts.second.title # => 'The egalitarian assumption of the modern citizen' # - # You may also set a :reject_if proc to silently ignore any new record + # You may also set a +:reject_if+ proc to silently ignore any new record # hashes if they fail to pass your criteria. For example, the previous # example could be rewritten as: # - # class Member < ActiveRecord::Base - # has_many :posts - # accepts_nested_attributes_for :posts, reject_if: proc { |attributes| attributes['title'].blank? } - # end + # class Member < ActiveRecord::Base + # has_many :posts + # accepts_nested_attributes_for :posts, reject_if: proc { |attributes| attributes['title'].blank? } + # end # # params = { member: { # name: 'joe', posts_attributes: [ @@ -132,21 +136,21 @@ module ActiveRecord # member.posts.first.title # => 'Kari, the awesome Ruby documentation browser!' # member.posts.second.title # => 'The egalitarian assumption of the modern citizen' # - # Alternatively, :reject_if also accepts a symbol for using methods: + # Alternatively, +:reject_if+ also accepts a symbol for using methods: # - # class Member < ActiveRecord::Base - # has_many :posts - # accepts_nested_attributes_for :posts, reject_if: :new_record? - # end + # class Member < ActiveRecord::Base + # has_many :posts + # accepts_nested_attributes_for :posts, reject_if: :new_record? + # end # - # class Member < ActiveRecord::Base - # has_many :posts - # accepts_nested_attributes_for :posts, reject_if: :reject_posts + # class Member < ActiveRecord::Base + # has_many :posts + # accepts_nested_attributes_for :posts, reject_if: :reject_posts # - # def reject_posts(attributed) - # attributed['title'].blank? - # end - # end + # def reject_posts(attributed) + # attributed['title'].blank? + # end + # end # # If the hash contains an <tt>id</tt> key that matches an already # associated record, the matching record will be modified: @@ -183,18 +187,41 @@ module ActiveRecord # member.save # member.reload.posts.length # => 1 # + # Nested attributes for an associated collection can also be passed in + # the form of a hash of hashes instead of an array of hashes: + # + # Member.create(name: 'joe', + # posts_attributes: { first: { title: 'Foo' }, + # second: { title: 'Bar' } }) + # + # has the same effect as + # + # Member.create(name: 'joe', + # posts_attributes: [ { title: 'Foo' }, + # { title: 'Bar' } ]) + # + # The keys of the hash which is the value for +:posts_attributes+ are + # ignored in this case. + # However, it is not allowed to use +'id'+ or +:id+ for one of + # such keys, otherwise the hash will be wrapped in an array and + # interpreted as an attribute hash for a single post. + # + # Passing attributes for an associated collection in the form of a hash + # of hashes can be used with hashes generated from HTTP/HTML parameters, + # where there maybe no natural way to submit an array of hashes. + # # === Saving # # All changes to models, including the destruction of those marked for # destruction, are saved and destroyed automatically and atomically when # the parent model is saved. This happens inside the transaction initiated - # by the parents save method. See ActiveRecord::AutosaveAssociation. + # by the parent's save method. See ActiveRecord::AutosaveAssociation. # # === Validating the presence of a parent model # # If you want to validate that a child record is associated with a parent - # record, you can use <tt>validates_presence_of</tt> and - # <tt>inverse_of</tt> as this example illustrates: + # record, you can use the +validates_presence_of+ method and the +:inverse_of+ + # key as this example illustrates: # # class Member < ActiveRecord::Base # has_many :posts, inverse_of: :member @@ -205,6 +232,27 @@ module ActiveRecord # belongs_to :member, inverse_of: :posts # validates_presence_of :member # end + # + # Note that if you do not specify the +:inverse_of+ option, then + # Active Record will try to automatically guess the inverse association + # based on heuristics. + # + # For one-to-one nested associations, if you build the new (in-memory) + # child object yourself before assignment, then this module will not + # overwrite it, e.g.: + # + # class Member < ActiveRecord::Base + # has_one :avatar + # accepts_nested_attributes_for :avatar + # + # def avatar + # super || build_avatar(width: 200) + # end + # end + # + # member = Member.new + # member.avatar_attributes = {icon: 'sad'} + # member.avatar.width # => 200 module ClassMethods REJECT_ALL_BLANK_PROC = proc { |attributes| attributes.all? { |key, value| key == '_destroy' || value.blank? } } @@ -219,29 +267,31 @@ module ActiveRecord # Allows you to specify a Proc or a Symbol pointing to a method # that checks whether a record should be built for a certain attribute # hash. The hash is passed to the supplied Proc or the method - # and it should return either +true+ or +false+. When no :reject_if + # and it should return either +true+ or +false+. When no +:reject_if+ # is specified, a record will be built for all attribute hashes that # do not have a <tt>_destroy</tt> value that evaluates to true. # Passing <tt>:all_blank</tt> instead of a Proc will create a proc # that will reject a record where all the attributes are blank excluding - # any value for _destroy. + # any value for +_destroy+. # [:limit] - # Allows you to specify the maximum number of the associated records that - # can be processed with the nested attributes. Limit also can be specified as a - # Proc or a Symbol pointing to a method that should return number. If the size of the - # nested attributes array exceeds the specified limit, NestedAttributes::TooManyRecords - # exception is raised. If omitted, any number associations can be processed. - # Note that the :limit option is only applicable to one-to-many associations. + # Allows you to specify the maximum number of associated records that + # can be processed with the nested attributes. Limit also can be specified + # as a Proc or a Symbol pointing to a method that should return a number. + # If the size of the nested attributes array exceeds the specified limit, + # NestedAttributes::TooManyRecords exception is raised. If omitted, any + # number of associations can be processed. + # Note that the +:limit+ option is only applicable to one-to-many + # associations. # [:update_only] # For a one-to-one association, this option allows you to specify how - # nested attributes are to be used when an associated record already + # nested attributes are going to be used when an associated record already # exists. In general, an existing record may either be updated with the # new set of attribute values or be replaced by a wholly new record - # containing those values. By default the :update_only option is +false+ + # containing those values. By default the +:update_only+ option is +false+ # and the nested attributes are used to update the existing record only # if they include the record's <tt>:id</tt> value. Otherwise a new # record will be instantiated and used to replace the existing one. - # However if the :update_only option is +true+, the nested attributes + # However if the +:update_only+ option is +true+, the nested attributes # are used to update the record's attributes always, regardless of # whether the <tt>:id</tt> is present. The option is ignored for collection # associations. @@ -260,8 +310,8 @@ module ActiveRecord options[:reject_if] = REJECT_ALL_BLANK_PROC if options[:reject_if] == :all_blank attr_names.each do |association_name| - if reflection = reflect_on_association(association_name) - reflection.options[:autosave] = true + if reflection = _reflect_on_association(association_name) + reflection.autosave = true add_autosave_association_callbacks(reflection) nested_attributes_options = self.nested_attributes_options.dup @@ -269,23 +319,36 @@ module ActiveRecord self.nested_attributes_options = nested_attributes_options type = (reflection.collection? ? :collection : :one_to_one) - - # def pirate_attributes=(attributes) - # assign_nested_attributes_for_one_to_one_association(:pirate, attributes, mass_assignment_options) - # end - generated_feature_methods.module_eval <<-eoruby, __FILE__, __LINE__ + 1 - if method_defined?(:#{association_name}_attributes=) - remove_method(:#{association_name}_attributes=) - end - def #{association_name}_attributes=(attributes) - assign_nested_attributes_for_#{type}_association(:#{association_name}, attributes) - end - eoruby + generate_association_writer(association_name, type) else raise ArgumentError, "No association found for name `#{association_name}'. Has it been defined yet?" end end end + + private + + # Generates a writer method for this association. Serves as a point for + # accessing the objects in the association. For example, this method + # could generate the following: + # + # def pirate_attributes=(attributes) + # assign_nested_attributes_for_one_to_one_association(:pirate, attributes) + # end + # + # This redirects the attempts to write objects in an association through + # the helper methods defined below. Makes it seem like the nested + # associations are just regular associations. + def generate_association_writer(association_name, type) + generated_association_methods.module_eval <<-eoruby, __FILE__, __LINE__ + 1 + if method_defined?(:#{association_name}_attributes=) + remove_method(:#{association_name}_attributes=) + end + def #{association_name}_attributes=(attributes) + assign_nested_attributes_for_#{type}_association(:#{association_name}, attributes) + end + eoruby + end end # Returns ActiveRecord::AutosaveAssociation::marked_for_destruction? It's @@ -319,20 +382,28 @@ module ActiveRecord def assign_nested_attributes_for_one_to_one_association(association_name, attributes) options = self.nested_attributes_options[association_name] attributes = attributes.with_indifferent_access + existing_record = send(association_name) - if (options[:update_only] || !attributes['id'].blank?) && (record = send(association_name)) && - (options[:update_only] || record.id.to_s == attributes['id'].to_s) - assign_to_or_mark_for_destruction(record, attributes, options[:allow_destroy]) unless call_reject_if(association_name, attributes) + if (options[:update_only] || !attributes['id'].blank?) && existing_record && + (options[:update_only] || existing_record.id.to_s == attributes['id'].to_s) + assign_to_or_mark_for_destruction(existing_record, attributes, options[:allow_destroy]) unless call_reject_if(association_name, attributes) elsif attributes['id'].present? - raise_nested_attributes_record_not_found(association_name, attributes['id']) + raise_nested_attributes_record_not_found!(association_name, attributes['id']) elsif !reject_new_record?(association_name, attributes) - method = "build_#{association_name}" - if respond_to?(method) - send(method, attributes.except(*UNASSIGNABLE_KEYS)) + assignable_attributes = attributes.except(*UNASSIGNABLE_KEYS) + + if existing_record && existing_record.new_record? + existing_record.assign_attributes(assignable_attributes) + association(association_name).initialize_attributes(existing_record) else - raise ArgumentError, "Cannot build association `#{association_name}'. Are you trying to build a polymorphic one-to-one association?" + method = "build_#{association_name}" + if respond_to?(method) + send(method, assignable_attributes) + else + raise ArgumentError, "Cannot build association `#{association_name}'. Are you trying to build a polymorphic one-to-one association?" + end end end end @@ -371,20 +442,7 @@ module ActiveRecord raise ArgumentError, "Hash or Array expected, got #{attributes_collection.class.name} (#{attributes_collection.inspect})" end - if limit = options[:limit] - limit = case limit - when Symbol - send(limit) - when Proc - limit.call - else - limit - end - - if limit && attributes_collection.size > limit - raise TooManyRecords, "Maximum #{limit} records are allowed. Got #{attributes_collection.size} records instead." - end - end + check_record_limit!(options[:limit], attributes_collection) if attributes_collection.is_a? Hash keys = attributes_collection.keys @@ -412,23 +470,44 @@ module ActiveRecord association.build(attributes.except(*UNASSIGNABLE_KEYS)) end elsif existing_record = existing_records.detect { |record| record.id.to_s == attributes['id'].to_s } - unless association.loaded? || call_reject_if(association_name, attributes) + unless call_reject_if(association_name, attributes) # Make sure we are operating on the actual object which is in the association's # proxy_target array (either by finding it, or adding it if not found) - target_record = association.target.detect { |record| record == existing_record } - + # Take into account that the proxy_target may have changed due to callbacks + target_record = association.target.detect { |record| record.id.to_s == attributes['id'].to_s } if target_record existing_record = target_record else - association.add_to_target(existing_record) + association.add_to_target(existing_record, :skip_callbacks) end - end - if !call_reject_if(association_name, attributes) assign_to_or_mark_for_destruction(existing_record, attributes, options[:allow_destroy]) end else - raise_nested_attributes_record_not_found(association_name, attributes['id']) + raise_nested_attributes_record_not_found!(association_name, attributes['id']) + end + end + end + + # Takes in a limit and checks if the attributes_collection has too many + # records. It accepts limit in the form of symbol, proc, or + # number-like object (anything that can be compared with an integer). + # + # Raises TooManyRecords error if the attributes_collection is + # larger than the limit. + def check_record_limit!(limit, attributes_collection) + if limit + limit = case limit + when Symbol + send(limit) + when Proc + limit.call + else + limit + end + + if limit && attributes_collection.size > limit + raise TooManyRecords, "Maximum #{limit} records are allowed. Got #{attributes_collection.size} records instead." end end end @@ -442,16 +521,21 @@ module ActiveRecord # Determines if a hash contains a truthy _destroy key. def has_destroy_flag?(hash) - ConnectionAdapters::Column.value_to_boolean(hash['_destroy']) + Type::Boolean.new.type_cast_from_user(hash['_destroy']) end - # Determines if a new record should be build by checking for + # Determines if a new record should be rejected by checking # has_destroy_flag? or if a <tt>:reject_if</tt> proc exists for this # association and evaluates to +true+. def reject_new_record?(association_name, attributes) has_destroy_flag?(attributes) || call_reject_if(association_name, attributes) end + # Determines if a record with the particular +attributes+ should be + # rejected by calling the reject_if Symbol or Proc (if defined). + # The reject_if option is defined by +accepts_nested_attributes_for+. + # + # Returns false if there is a +destroy_flag+ on the attributes. def call_reject_if(association_name, attributes) return false if has_destroy_flag?(attributes) case callback = self.nested_attributes_options[association_name][:reject_if] @@ -462,8 +546,8 @@ module ActiveRecord end end - def raise_nested_attributes_record_not_found(association_name, record_id) - raise RecordNotFound, "Couldn't find #{self.class.reflect_on_association(association_name).klass.name} with ID=#{record_id} for #{self.class.name} with ID=#{id}" + def raise_nested_attributes_record_not_found!(association_name, record_id) + raise RecordNotFound, "Couldn't find #{self.class._reflect_on_association(association_name).klass.name} with ID=#{record_id} for #{self.class.name} with ID=#{id}" end end end |