module Sequel::Plugins::ClassTableInheritance::ClassMethods

  1. lib/sequel/plugins/class_table_inheritance.rb
Parent: ClassTableInheritance

Attributes

cti_base_model [R]

The parent/root/base model for this class table inheritance hierarchy. This is the only model in the hierarchy that load the class_table_inheritance plugin.
cti_columns [R]

Hash with table name symbol keys and arrays of column symbol values, giving the columns to update in each backing database table.
cti_key [R]

The column containing the class name as a string. Used to return instances of subclasses when calling the superclass’s load method.
cti_table_map [R]

A hash with class name symbol keys and table name symbol values. Specified with the :table_map option to the plugin, and used if the implicit naming is incorrect.
cti_tables [R]

An array of table symbols that back this model. The first is #cti_base_model table symbol, and the last is the current model table symbol.

Public Instance methods

inherited (subclass)

Add the appropriate data structures to the subclass. Does not allow anonymous subclasses to be created, since they would not be mappable to a table.

[show source] 
# File lib/sequel/plugins/class_table_inheritance.rb, line 128
def inherited(subclass)
  cc = cti_columns
  ck = cti_key
  ct = cti_tables.dup
  ctm = cti_table_map.dup
  cbm = cti_base_model
  pk = primary_key
  ds = dataset
  subclass.instance_eval do
    raise(Error, "cannot create anonymous subclass for model class using class_table_inheritance") if !(n = name) || n.empty?
    table = ctm[n.to_sym] || implicit_table_name
    columns = db.from(table).columns
    @cti_key = ck 
    @cti_tables = ct + [table]
    @cti_columns = cc.merge(table=>columns)
    @cti_table_map = ctm
    @cti_base_model = cbm
    # Need to set dataset and columns before calling super so that
    # the main column accessor module is included in the class before any
    # plugin accessor modules (such as the lazy attributes accessor module).
    set_dataset(ds.join(table, [pk]))
    set_columns(self.columns)
  end
  super
  subclass.instance_eval do
    m = method(:constantize)
    dataset.row_proc = if cti_key
      lambda{|r| (m.call(r[ck]) rescue subclass).call(r)}
    else
      subclass
    end
    (columns - [cbm.primary_key]).each{|a| define_lazy_attribute_getter(a)}
    cti_tables.reverse.each do |table|
      db.schema(table).each{|k,v| db_schema[k] = v}
    end
  end
end
primary_key ()

The primary key in the parent/base/root model, which should have a foreign key with the same name referencing it in each model subclass.

[show source] 
# File lib/sequel/plugins/class_table_inheritance.rb, line 168
def primary_key
  return super if self == cti_base_model
  cti_base_model.primary_key
end
table_name ()

The table name for the current model class’s main table (not used by any superclasses).

[show source] 
# File lib/sequel/plugins/class_table_inheritance.rb, line 175
def table_name
  self == cti_base_model ? super : cti_tables.last
end