Module: Sequel::Plugins::SingleTableInheritance::ClassMethods

Attributes

sti_dataset	[R]	The base dataset for STI, to which filters are added to get only the models for the specific STI subclass.
sti_key	[R]	The column name holding the STI key for this model
sti_key_array	[R]	Array holding keys for all subclasses of this class, used for the dataset filter in subclasses. Nil in the main class.
sti_key_chooser	[R]	A proc which returns the value to use for new instances. This defaults to a lookup in the key map.
sti_key_map	[R]	A hash/proc with class keys and column value values, mapping the the class to a particular value given to the sti_key column. Used to set the column value when creating objects, and for the filter when retrieving objects in subclasses.
sti_model_map	[R]	A hash/proc with column value keys and class values, mapping the value of the sti_key column to the appropriate class to use.

Public Instance methods

inherited(subclass)

Copy the necessary attributes to the subclasses, and filter the subclass‘s dataset based on the sti_kep_map entry for the class.

[Source]

     # File lib/sequel/plugins/single_table_inheritance.rb, line 144
144:         def inherited(subclass)
145:           super
146:           sk = sti_key
147:           sd = sti_dataset
148:           skm = sti_key_map
149:           smm = sti_model_map
150:           skc = sti_key_chooser
151:           key = Array(skm[subclass]).dup
152:           sti_subclass_added(key)
153:           rp = dataset.row_proc
154:           subclass.set_dataset(sd.filter(SQL::QualifiedIdentifier.new(table_name, sk)=>key), :inherited=>true)
155:           subclass.instance_eval do
156:             dataset.row_proc = rp
157:             @sti_key = sk
158:             @sti_key_array = key
159:             @sti_dataset = sd
160:             @sti_key_map = skm
161:             @sti_model_map = smm
162:             @sti_key_chooser = skc
163:             self.simple_table = nil
164:           end
165:         end

sti_load(r)

Return an instance of the class specified by sti_key, used by the row_proc.

[Source]

     # File lib/sequel/plugins/single_table_inheritance.rb, line 169
169:         def sti_load(r)
170:           sti_class(sti_model_map[r[sti_key]]).call(r)
171:         end

sti_subclass_added(key)

Make sure that all subclasses of the parent class correctly include keys for all of their descendant classes.

[Source]

     # File lib/sequel/plugins/single_table_inheritance.rb, line 175
175:         def sti_subclass_added(key)
176:           if sti_key_array
177:             Sequel.synchronize{sti_key_array.push(*Array(key))}
178:             superclass.sti_subclass_added(key)
179:           end
180:         end