module Sequel::Model::Associations::ClassMethods
Each kind of association adds a number of instance methods to the model class which are specialized according to the association type and optional parameters given in the definition. Example:
class Project < Sequel::Model many_to_one :portfolio # or: one_to_one :portfolio one_to_many :milestones # or: many_to_many :milestones end
The project class now has the following instance methods:
- portfolio
-
Returns the associated portfolio.
- portfolio=(obj)
-
Sets the associated portfolio to the object, but the change is not persisted until you save the record (for
many_to_one
associations). - portfolio_dataset
-
Returns a dataset that would return the associated portfolio, only useful in fairly specific circumstances.
- milestones
-
Returns an array of associated milestones
- add_milestone(obj)
-
Associates the passed milestone with this object.
- remove_milestone(obj)
-
Removes the association with the passed milestone.
- remove_all_milestones
-
Removes associations with all associated milestones.
- milestones_dataset
-
Returns a dataset that would return the associated milestones, allowing for further filtering/limiting/etc.
If you want to override the behavior of the add_/remove_/remove_all_/ methods or the association setter method, use the :adder, :remover, :clearer, and/or :setter options. These options override the default behavior.
By default the classes for the associations are inferred from the association name, so for example the Project#portfolio will return an instance of Portfolio, and Project#milestones will return an array of Milestone instances. You can use the :class option to change which class is used.
Association definitions are also reflected by the class, e.g.:
Project.associations => [:portfolio, :milestones] Project.association_reflection(:portfolio) => #<Sequel::Model::Associations::ManyToOneAssociationReflection Project.many_to_one :portfolio>
Associations
should not have the same names as any of the columns in the model's current table they reference. If you are dealing with an existing schema that has a column named status, you can't name the association status, you'd have to name it foo_status or something else. If you give an association the same name as a column, you will probably end up with an association that doesn't work, or a SystemStackError.
For a more in depth general overview, as well as a reference guide, see the Association Basics guide. For examples of advanced usage, see the Advanced Associations guide.
Attributes
All association reflections defined for this model (default: {}).
Hash
with column symbol keys and arrays of many_to_one
association symbols that should be cleared when the column value changes.
Whether association metadata should be cached in the association reflection. If not cached, it will be computed on demand. In general you only want to set this to false when using code reloading. When using code reloading, setting this will make sure that if an associated class is removed or modified, this class will not have a reference to the previous class.
The default options to use for all associations. This hash is merged into the association reflection hash for all association reflections.
The default options to use for all associations of a given type. This is a hash keyed by association type symbol. If there is a value for the association type symbol key, the resulting hash will be merged into the association reflection hash for all association reflections of that type.
The default :eager_limit_strategy option to use for limited or offset associations (default: true, causing Sequel
to use what it considers the most appropriate strategy).
Public Instance Methods
Array
of all association reflections for this model class
# File lib/sequel/model/associations.rb 1600 def all_association_reflections 1601 association_reflections.values 1602 end
Associates a related model with the current model. The following types are supported:
- :many_to_one
-
Foreign key in current model's table points to associated model's primary key. Each associated model object can be associated with more than one current model objects. Each current model object can be associated with only one associated model object.
- :one_to_many
-
Foreign key in associated model's table points to this model's primary key. Each current model object can be associated with more than one associated model objects. Each associated model object can be associated with only one current model object.
- :one_through_one
-
Similar to
many_to_many
in terms of foreign keys, but only one object is associated to the current object through the association. Provides only getter methods, no setter or modification methods. - :one_to_one
-
Similar to
one_to_many
in terms of foreign keys, but only one object is associated to the current object through the association. The methods created are similar tomany_to_one
, except that theone_to_one
setter method saves the passed object. - :many_to_many
-
A join table is used that has a foreign key that points to this model's primary key and a foreign key that points to the associated model's primary key. Each current model object can be associated with many associated model objects, and each associated model object can be associated with many current model objects.
The following options can be supplied:
Multiple Types¶ ↑
- :adder
-
Proc used to define the private add* method for doing the database work to associate the given object to the current object (*_to_many assocations). Set to nil to not define a add_* method for the association.
- :after_add
-
Symbol
, Proc, or array of both/either specifying a callback to call after a new item is added to the association. - :after_load
-
Symbol
, Proc, or array of both/either specifying a callback to call after the associated record(s) have been retrieved from the database. - :after_remove
-
Symbol
, Proc, or array of both/either specifying a callback to call after an item is removed from the association. - :after_set
-
Symbol
, Proc, or array of both/either specifying a callback to call after an item is set using the association setter method. - :allow_eager
-
If set to false, you cannot load the association eagerly via eager or eager_graph
- :allow_eager_graph
-
If set to false, you cannot load the association eagerly via eager_graph.
- :allow_filtering_by
-
If set to false, you cannot use the association when filtering
- :before_add
-
Symbol
, Proc, or array of both/either specifying a callback to call before a new item is added to the association. - :before_remove
-
Symbol
, Proc, or array of both/either specifying a callback to call before an item is removed from the association. - :before_set
-
Symbol
, Proc, or array of both/either specifying a callback to call before an item is set using the association setter method. - :cartesian_product_number
-
the number of joins completed by this association that could cause more than one row for each row in the current table (default: 0 for
many_to_one
,one_to_one
, andone_through_one
associations, 1 forone_to_many
andmany_to_many
associations). - :class
-
The associated class or its name as a string or symbol. If not given, uses the association's name, which is camelized (and singularized unless the type is :many_to_one, :one_to_one, or
one_through_one
). If this is specified as a string or symbol, you must specify the full class name (e.g. “::SomeModule::MyModel”). - :class_namespace
-
If :class is given as a string or symbol, sets the default namespace in which to look for the class.
class: 'Foo', class_namespace: 'Bar'
looks for::Bar::Foo
.) - :clearer
-
Proc used to define the private remove_all* method for doing the database work to remove all objects associated to the current object (*_to_many assocations). Set to nil to not define a remove_all_* method for the association.
- :clone
-
Merge the current options and block into the options and block used in defining the given association. Can be used to DRY up a bunch of similar associations that all share the same options such as :class and :key, while changing the order and block used.
- :conditions
-
The conditions to use to filter the association, can be any argument passed to where. This option is not respected when using eager_graph or association_join, unless it is hash or array of two element arrays. Consider also specifying the :graph_block option if the value for this option is not a hash or array of two element arrays and you plan to use this association in eager_graph or association_join.
- :dataset
-
A proc that is used to define the method to get the base dataset to use (before the other options are applied). If the proc accepts an argument, it is passed the related association reflection. It is a best practice to always have the dataset accept an argument and use the argument to return the appropriate dataset.
- :distinct
-
Use the DISTINCT clause when selecting associating object, both when lazy loading and eager loading via .eager (but not when using .eager_graph).
- :eager
-
The associations to eagerly load via
eager
when loading the associated object(s). - :eager_block
-
If given, use the block instead of the default block when eagerly loading. To not use a block when eager loading (when one is used normally), set to nil.
- :eager_graph
-
The associations to eagerly load via
eager_graph
when loading the associated object(s).many_to_many
associations with this option cannot be eagerly loaded viaeager
. - :eager_grapher
-
A proc to use to implement eager loading via
eager_graph
, overriding the default. Takes an options hash with at least the entries :self (the receiver of the eager_graph call), :table_alias (the alias to use for table to graph into the association), and :implicit_qualifier (the alias that was used for the current table). Should return a copy of the dataset with the association graphed into it. - :eager_limit_strategy
-
Determines the strategy used for enforcing limits and offsets when eager loading associations via the
eager
method. - :eager_loader
-
A proc to use to implement eager loading, overriding the default. Takes a single hash argument, with at least the keys: :rows, which is an array of current model instances, :associations, which is a hash of dependent associations, :self, which is the dataset doing the eager loading, :eager_block, which is a dynamic callback that should be called with the dataset, and :id_map, which is a mapping of key values to arrays of current model instances. In the proc, the associated records should be queried from the database and the associations cache for each record should be populated.
- :eager_loader_key
-
A symbol for the key column to use to populate the key_hash for the eager loader. Can be set to nil to not populate the key_hash.
- :extend
-
A module or array of modules to extend the dataset with.
- :filter_limit_strategy
-
Determines the strategy used for enforcing limits and offsets when filtering by limited associations. Possible options are :window_function, :distinct_on, or :correlated_subquery depending on association type and database type.
- :graph_alias_base
-
The base name to use for the table alias when eager graphing. Defaults to the name of the association. If the alias name has already been used in the query,
Sequel
will create a unique alias by appending a numeric suffix (e.g. alias_0, alias_1, …) until the alias is unique. - :graph_block
-
The block to pass to join_table when eagerly loading the association via
eager_graph
. - :graph_conditions
-
The additional conditions to use on the
SQL
join when eagerly loading the association viaeager_graph
. Should be a hash or an array of two element arrays. If not specified, the :conditions option is used if it is a hash or array of two element arrays. - :graph_join_type
-
The type of
SQL
join to use when eagerly loading the association via eager_graph. Defaults to :left_outer. - :graph_only_conditions
-
The conditions to use on the
SQL
join when eagerly loading the association viaeager_graph
, instead of the default conditions specified by the foreign/primary keys. This option causes the :graph_conditions option to be ignored. - :graph_order
-
the order to use when using eager_graph, instead of the default order. This should be used in the case where :order contains an identifier qualified by the table's name, which may not match the alias used when eager graphing. By setting this to the unqualified identifier, it will be automatically qualified when using eager_graph.
- :graph_select
-
A column or array of columns to select from the associated table when eagerly loading the association via
eager_graph
. Defaults to all columns in the associated table. - :instance_specific
-
Marks the association as instance specific. Should be used if the association block uses instance specific state, or transient state (accessing current date/time, etc.).
- :limit
-
Limit the number of records to the provided value. Use an array with two elements for the value to specify a limit (first element) and an offset (second element).
- :methods_module
-
The module that methods the association creates will be placed into. Defaults to the module containing the model's columns.
- :no_association_method
-
Do not add a method for the association. This can save memory if the association method is never used.
- :no_dataset_method
-
Do not add a method for the association dataset. This can save memory if the dataset method is never used.
- :order
-
the column(s) by which to order the association dataset. Can be a singular column symbol or an array of column symbols.
- :order_eager_graph
-
Whether to add the association's order to the graphed dataset's order when graphing via
eager_graph
. Defaults to true, so set to false to disable. - :read_only
-
Do not add a setter method (for
many_to_one
orone_to_one
associations), or add_/remove_/remove_all_ methods (forone_to_many
andmany_to_many
associations). - :reciprocal
-
the symbol name of the reciprocal association, if it exists. By default,
Sequel
will try to determine it by looking at the associated model's assocations for a association that matches the current association's key(s). Set to nil to not use a reciprocal. - :remover
-
Proc used to define the private remove* method for doing the database work to remove the association between the given object and the current object (*_to_many assocations). Set to nil to not define a remove_* method for the association.
- :select
-
the columns to select. Defaults to the associated class's table_name.* in an association that uses joins, which means it doesn't include the attributes from the join table. If you want to include the join table attributes, you can use this option, but beware that the join table attributes can clash with attributes from the model table, so you should alias any attributes that have the same name in both the join table and the associated table.
- :setter
-
Proc used to define the private _*= method for doing the work to setup the assocation between the given object and the current object (*_to_one associations). Set to nil to not define a setter method for the association.
- :subqueries_per_union
-
The number of subqueries to use in each UNION query, for eager loading limited associations using the default :union strategy.
- :validate
-
Set to false to not validate when implicitly saving any associated object.
:many_to_one¶ ↑
- :key
-
foreign key in current model's table that references associated model's primary key, as a symbol. Defaults to :“#{name}_id”. Can use an array of symbols for a composite key association.
- :key_column
-
Similar to, and usually identical to, :key, but :key refers to the model method to call, where :key_column refers to the underlying column. Should only be used if the model method differs from the foreign key column, in conjunction with defining a model alias method for the key column.
- :primary_key
-
column in the associated table that :key option references, as a symbol. Defaults to the primary key of the associated table. Can use an array of symbols for a composite key association.
- :primary_key_method
-
the method symbol or array of method symbols to call on the associated object to get the foreign key values. Defaults to :primary_key option.
- :qualify
-
Whether to use qualified primary keys when loading the association. The default is true, so you must set to false to not qualify. Qualification rarely causes problems, but it's necessary to disable in some cases, such as when you are doing a JOIN USING operation on the column on
Oracle
.
:one_to_many and :one_to_one¶ ↑
- :key
-
foreign key in associated model's table that references current model's primary key, as a symbol. Defaults to :“#{self.name.underscore}_id”. Can use an array of symbols for a composite key association.
- :key_method
-
the method symbol or array of method symbols to call on the associated object to get the foreign key values. Defaults to :key option.
- :primary_key
-
column in the current table that :key option references, as a symbol. Defaults to primary key of the current table. Can use an array of symbols for a composite key association.
- :primary_key_column
-
Similar to, and usually identical to, :primary_key, but :primary_key refers to the model method call, where :primary_key_column refers to the underlying column. Should only be used if the model method differs from the primary key column, in conjunction with defining a model alias method for the primary key column.
- :raise_on_save_failure
-
Do not raise exceptions for hook or validation failures when saving associated objects in the add/remove methods (return nil instead) [one_to_many only].
:many_to_many and :one_through_one¶ ↑
- :graph_join_table_block
-
The block to pass to
join_table
for the join table when eagerly loading the association viaeager_graph
. - :graph_join_table_conditions
-
The additional conditions to use on the
SQL
join for the join table when eagerly loading the association viaeager_graph
. Should be a hash or an array of two element arrays. - :graph_join_table_join_type
-
The type of
SQL
join to use for the join table when eagerly loading the association viaeager_graph
. Defaults to the :graph_join_type option or :left_outer. - :graph_join_table_only_conditions
-
The conditions to use on the
SQL
join for the join table when eagerly loading the association viaeager_graph
, instead of the default conditions specified by the foreign/primary keys. This option causes the :graph_join_table_conditions option to be ignored. - :join_table
-
name of table that includes the foreign keys to both the current model and the associated model, as a symbol. Defaults to the name of current model and name of associated model, pluralized, underscored, sorted, and joined with '_'.
- :join_table_block
-
proc that can be used to modify the dataset used in the add/remove/remove_all methods. Should accept a dataset argument and return a modified dataset if present.
- :join_table_db
-
When retrieving records when using lazy loading or eager loading via
eager
, instead of a join between to the join table and the associated table, use a separate query for the join table using the givenDatabase
object. - :left_key
-
foreign key in join table that points to current model's primary key, as a symbol. Defaults to :“#{self.name.underscore}_id”. Can use an array of symbols for a composite key association.
- :left_primary_key
-
column in current table that :left_key points to, as a symbol. Defaults to primary key of current table. Can use an array of symbols for a composite key association.
- :left_primary_key_column
-
Similar to, and usually identical to, :left_primary_key, but :left_primary_key refers to the model method to call, where :left_primary_key_column refers to the underlying column. Should only be used if the model method differs from the left primary key column, in conjunction with defining a model alias method for the left primary key column.
- :right_key
-
foreign key in join table that points to associated model's primary key, as a symbol. Defaults to :“#{name.to_s.singularize}_id”. Can use an array of symbols for a composite key association.
- :right_primary_key
-
column in associated table that :right_key points to, as a symbol. Defaults to primary key of the associated table. Can use an array of symbols for a composite key association.
- :right_primary_key_method
-
the method symbol or array of method symbols to call on the associated object to get the foreign key values for the join table. Defaults to :right_primary_key option.
- :uniq
-
Adds a after_load callback that makes the array of objects unique.
# File lib/sequel/model/associations.rb 1837 def associate(type, name, opts = OPTS, &block) 1838 raise(Error, 'invalid association type') unless assoc_class = Sequel.synchronize{ASSOCIATION_TYPES[type]} 1839 raise(Error, 'Model.associate name argument must be a symbol') unless name.is_a?(Symbol) 1840 1841 # dup early so we don't modify opts 1842 orig_opts = opts.dup 1843 1844 if opts[:clone] 1845 cloned_assoc = association_reflection(opts[:clone]) 1846 remove_class_name = orig_opts[:class] && !orig_opts[:class_name] 1847 orig_opts = cloned_assoc[:orig_opts].merge(orig_opts) 1848 orig_opts.delete(:class_name) if remove_class_name 1849 end 1850 1851 opts = Hash[default_association_options] 1852 if type_options = default_association_type_options[type] 1853 opts.merge!(type_options) 1854 end 1855 opts.merge!(orig_opts) 1856 opts.merge!(:type => type, :name => name, :cache=>({} if cache_associations), :model => self) 1857 1858 opts[:block] = block if block 1859 opts[:instance_specific] = true if orig_opts[:dataset] 1860 if !opts.has_key?(:instance_specific) && (block || orig_opts[:block]) 1861 # It's possible the association is instance specific, in that it depends on 1862 # values other than the foreign key value. This needs to be checked for 1863 # in certain places to disable optimizations. 1864 opts[:instance_specific] = _association_instance_specific_default(name) 1865 end 1866 if (orig_opts[:instance_specific] || orig_opts[:dataset]) && !opts.has_key?(:allow_eager) && !opts[:eager_loader] 1867 # For associations explicitly marked as instance specific, or that use the 1868 # :dataset option, where :allow_eager is not set, and no :eager_loader is 1869 # provided, disallow eager loading. In these cases, eager loading is 1870 # unlikely to work. This is not done for implicit setting of :instance_specific, 1871 # because implicit use is done by default for all associations with blocks, 1872 # and the vast majority of associations with blocks use the block for filtering 1873 # in a manner compatible with eager loading. 1874 opts[:allow_eager] = false 1875 end 1876 opts = assoc_class.new.merge!(opts) 1877 1878 if opts[:clone] && !opts.cloneable?(cloned_assoc) 1879 raise(Error, "cannot clone an association to an association of different type (association #{name} with type #{type} cloning #{opts[:clone]} with type #{cloned_assoc[:type]})") 1880 end 1881 1882 opts[:use_placeholder_loader] = !opts[:instance_specific] && !opts[:eager_graph] 1883 opts[:eager_block] = opts[:block] unless opts.include?(:eager_block) 1884 opts[:graph_join_type] ||= :left_outer 1885 opts[:order_eager_graph] = true unless opts.include?(:order_eager_graph) 1886 conds = opts[:conditions] 1887 opts[:graph_alias_base] ||= name 1888 opts[:graph_conditions] = conds if !opts.include?(:graph_conditions) and Sequel.condition_specifier?(conds) 1889 opts[:graph_conditions] = opts.fetch(:graph_conditions, []).to_a 1890 opts[:graph_select] = Array(opts[:graph_select]) if opts[:graph_select] 1891 [:before_add, :before_remove, :after_add, :after_remove, :after_load, :before_set, :after_set].each do |cb_type| 1892 opts[cb_type] = Array(opts[cb_type]) if opts[cb_type] 1893 end 1894 1895 if opts[:extend] 1896 opts[:extend] = Array(opts[:extend]) 1897 opts[:reverse_extend] = opts[:extend].reverse 1898 end 1899 1900 late_binding_class_option(opts, opts.returns_array? ? singularize(name) : name) 1901 1902 # Remove :class entry if it exists and is nil, to work with cached_fetch 1903 opts.delete(:class) unless opts[:class] 1904 1905 def_association(opts) 1906 1907 orig_opts.delete(:clone) 1908 opts[:orig_class] = orig_opts[:class] || orig_opts[:class_name] 1909 orig_opts.merge!(:class_name=>opts[:class_name], :class=>opts[:class], :block=>opts[:block]) 1910 opts[:orig_opts] = orig_opts 1911 # don't add to association_reflections until we are sure there are no errors 1912 association_reflections[name] = opts 1913 end
The association reflection hash for the association of the given name.
# File lib/sequel/model/associations.rb 1916 def association_reflection(name) 1917 association_reflections[name] 1918 end
Array
of association name symbols
# File lib/sequel/model/associations.rb 1921 def associations 1922 association_reflections.keys 1923 end
Eager load the association with the given eager loader options.
# File lib/sequel/model/associations.rb 1926 def eager_load_results(opts, eo, &block) 1927 opts.eager_load_results(eo, &block) 1928 end
Finalize all associations such that values that are looked up dynamically in associated classes are set statically. As this modifies the associations, it must be done before calling freeze.
# File lib/sequel/model/associations.rb 1945 def finalize_associations 1946 @association_reflections.each_value(&:finalize) 1947 end
Freeze association related metadata when freezing model class.
# File lib/sequel/model/associations.rb 1931 def freeze 1932 @association_reflections.freeze.each_value(&:freeze) 1933 @autoreloading_associations.freeze.each_value(&:freeze) 1934 @default_association_options.freeze 1935 @default_association_type_options.freeze 1936 @default_association_type_options.each_value(&:freeze) 1937 1938 super 1939 end
Shortcut for adding a many_to_many
association, see associate
# File lib/sequel/model/associations.rb 1950 def many_to_many(name, opts=OPTS, &block) 1951 associate(:many_to_many, name, opts, &block) 1952 end
Shortcut for adding a many_to_one
association, see associate
# File lib/sequel/model/associations.rb 1955 def many_to_one(name, opts=OPTS, &block) 1956 associate(:many_to_one, name, opts, &block) 1957 end
Shortcut for adding a one_through_one
association, see associate
# File lib/sequel/model/associations.rb 1960 def one_through_one(name, opts=OPTS, &block) 1961 associate(:one_through_one, name, opts, &block) 1962 end
Shortcut for adding a one_to_many
association, see associate
# File lib/sequel/model/associations.rb 1965 def one_to_many(name, opts=OPTS, &block) 1966 associate(:one_to_many, name, opts, &block) 1967 end
Shortcut for adding a one_to_one
association, see associate
# File lib/sequel/model/associations.rb 1970 def one_to_one(name, opts=OPTS, &block) 1971 associate(:one_to_one, name, opts, &block) 1972 end
Private Instance Methods
The default value for the instance_specific option, if the association could be instance specific and the :instance_specific option is not specified.
# File lib/sequel/model/associations.rb 1981 def _association_instance_specific_default(_) 1982 true 1983 end
The module to use for the association's methods. Defaults to the overridable_methods_module.
# File lib/sequel/model/associations.rb 1987 def association_module(opts=OPTS) 1988 opts.fetch(:methods_module, overridable_methods_module) 1989 end
Add a method to the module included in the class, so the method can be easily overridden in the class itself while allowing for super to be called.
# File lib/sequel/model/associations.rb 1994 def association_module_def(name, opts=OPTS, &block) 1995 mod = association_module(opts) 1996 mod.send(:define_method, name, &block) 1997 mod.send(:alias_method, name, name) 1998 end
Add a method to the module included in the class, so the method can be easily overridden in the class itself while allowing for super to be called. This method allows passing keywords through the defined methods.
# File lib/sequel/model/associations.rb 2004 def association_module_delegate_def(name, opts, &block) 2005 mod = association_module(opts) 2006 mod.send(:define_method, name, &block) 2007 # :nocov: 2008 mod.send(:ruby2_keywords, name) if mod.respond_to?(:ruby2_keywords, true) 2009 # :nocov: 2010 mod.send(:alias_method, name, name) 2011 end
Add a private method to the module included in the class.
# File lib/sequel/model/associations.rb 2014 def association_module_private_def(name, opts=OPTS, &block) 2015 association_module_def(name, opts, &block) 2016 association_module(opts).send(:private, name) 2017 end
Delegate to the type-specific association method to setup the association, and define the association instance methods.
# File lib/sequel/model/associations.rb 2021 def def_association(opts) 2022 send(:"def_#{opts[:type]}", opts) 2023 def_association_instance_methods(opts) 2024 end
Define all of the association instance methods for this association.
# File lib/sequel/model/associations.rb 2034 def def_association_instance_methods(opts) 2035 # Always set the method names in the association reflection, even if they 2036 # are not used, for backwards compatibility. 2037 opts[:dataset_method] = :"#{opts[:name]}_dataset" 2038 if opts.returns_array? 2039 sname = singularize(opts[:name]) 2040 opts[:_add_method] = :"_add_#{sname}" 2041 opts[:add_method] = :"add_#{sname}" 2042 opts[:_remove_method] = :"_remove_#{sname}" 2043 opts[:remove_method] = :"remove_#{sname}" 2044 opts[:_remove_all_method] = :"_remove_all_#{opts[:name]}" 2045 opts[:remove_all_method] = :"remove_all_#{opts[:name]}" 2046 else 2047 opts[:_setter_method] = :"_#{opts[:name]}=" 2048 opts[:setter_method] = :"#{opts[:name]}=" 2049 end 2050 2051 association_module_def(opts.dataset_method, opts){_dataset(opts)} unless opts[:no_dataset_method] 2052 if opts[:block] 2053 opts[:block_method] = Plugins.def_sequel_method(association_module(opts), "#{opts[:name]}_block", 1, &opts[:block]) 2054 end 2055 opts[:dataset_opt_arity] = opts[:dataset].arity == 0 ? 0 : 1 2056 opts[:dataset_opt_method] = Plugins.def_sequel_method(association_module(opts), "#{opts[:name]}_dataset_opt", opts[:dataset_opt_arity], &opts[:dataset]) 2057 def_association_method(opts) unless opts[:no_association_method] 2058 2059 return if opts[:read_only] 2060 2061 if opts[:setter] && opts[:_setter] 2062 # This is backwards due to backwards compatibility 2063 association_module_private_def(opts[:_setter_method], opts, &opts[:setter]) 2064 association_module_def(opts[:setter_method], opts, &opts[:_setter]) 2065 end 2066 2067 if adder = opts[:adder] 2068 association_module_private_def(opts[:_add_method], opts, &adder) 2069 association_module_delegate_def(opts[:add_method], opts){|o,*args| add_associated_object(opts, o, *args)} 2070 end 2071 2072 if remover = opts[:remover] 2073 association_module_private_def(opts[:_remove_method], opts, &remover) 2074 association_module_delegate_def(opts[:remove_method], opts){|o,*args| remove_associated_object(opts, o, *args)} 2075 end 2076 2077 if clearer = opts[:clearer] 2078 association_module_private_def(opts[:_remove_all_method], opts, &clearer) 2079 association_module_delegate_def(opts[:remove_all_method], opts){|*args| remove_all_associated_objects(opts, *args)} 2080 end 2081 end
Adds the association method to the association methods module.
# File lib/sequel/model/associations.rb 2027 def def_association_method(opts) 2028 association_module_def(opts.association_method, opts) do |dynamic_opts=OPTS, &block| 2029 load_associated_objects(opts, dynamic_opts, &block) 2030 end 2031 end
Configures many_to_many
and one_through_one
association reflection and adds the related association methods
# File lib/sequel/model/associations.rb 2084 def def_many_to_many(opts) 2085 one_through_one = opts[:type] == :one_through_one 2086 left = (opts[:left_key] ||= opts.default_left_key) 2087 lcks = opts[:left_keys] = Array(left) 2088 right = (opts[:right_key] ||= opts.default_right_key) 2089 rcks = opts[:right_keys] = Array(right) 2090 left_pk = (opts[:left_primary_key] ||= self.primary_key) 2091 opts[:eager_loader_key] = left_pk unless opts.has_key?(:eager_loader_key) 2092 lcpks = opts[:left_primary_keys] = Array(left_pk) 2093 lpkc = opts[:left_primary_key_column] ||= left_pk 2094 lpkcs = opts[:left_primary_key_columns] ||= Array(lpkc) 2095 raise(Error, "mismatched number of left keys: #{lcks.inspect} vs #{lcpks.inspect}") unless lcks.length == lcpks.length 2096 if opts[:right_primary_key] 2097 rcpks = Array(opts[:right_primary_key]) 2098 raise(Error, "mismatched number of right keys: #{rcks.inspect} vs #{rcpks.inspect}") unless rcks.length == rcpks.length 2099 end 2100 opts[:uses_left_composite_keys] = lcks.length > 1 2101 uses_rcks = opts[:uses_right_composite_keys] = rcks.length > 1 2102 opts[:cartesian_product_number] ||= one_through_one ? 0 : 1 2103 join_table = (opts[:join_table] ||= opts.default_join_table) 2104 opts[:left_key_alias] ||= opts.default_associated_key_alias 2105 opts[:graph_join_table_join_type] ||= opts[:graph_join_type] 2106 if opts[:uniq] 2107 opts[:after_load] ||= [] 2108 opts[:after_load].unshift(:array_uniq!) 2109 end 2110 if join_table_db = opts[:join_table_db] 2111 opts[:use_placeholder_loader] = false 2112 opts[:allow_eager_graph] = false 2113 opts[:allow_filtering_by] = false 2114 opts[:eager_limit_strategy] = nil 2115 join_table_ds = join_table_db.from(join_table) 2116 opts[:dataset] ||= proc do |r| 2117 vals = join_table_ds.where(lcks.zip(lcpks.map{|k| get_column_value(k)})).select_map(right) 2118 ds = r.associated_dataset.where(opts.right_primary_key => vals) 2119 if uses_rcks 2120 vals.delete_if{|v| v.any?(&:nil?)} 2121 else 2122 vals.delete(nil) 2123 end 2124 ds = ds.clone(:no_results=>true) if vals.empty? 2125 ds 2126 end 2127 opts[:eager_loader] ||= proc do |eo| 2128 h = eo[:id_map] 2129 assign_singular = opts.assign_singular? 2130 rpk = opts.right_primary_key 2131 name = opts[:name] 2132 2133 join_map = join_table_ds.where(left=>h.keys).select_hash_groups(right, left) 2134 2135 if uses_rcks 2136 join_map.delete_if{|v,| v.any?(&:nil?)} 2137 else 2138 join_map.delete(nil) 2139 end 2140 2141 eo = Hash[eo] 2142 2143 if join_map.empty? 2144 eo[:no_results] = true 2145 else 2146 join_map.each_value do |vs| 2147 vs.replace(vs.flat_map{|v| h[v]}) 2148 vs.uniq! 2149 end 2150 2151 eo[:loader] = false 2152 eo[:right_keys] = join_map.keys 2153 end 2154 2155 opts[:model].eager_load_results(opts, eo) do |assoc_record| 2156 rpkv = if uses_rcks 2157 assoc_record.values.values_at(*rpk) 2158 else 2159 assoc_record.values[rpk] 2160 end 2161 2162 objects = join_map[rpkv] 2163 2164 if assign_singular 2165 objects.each do |object| 2166 object.associations[name] ||= assoc_record 2167 end 2168 else 2169 objects.each do |object| 2170 object.associations[name].push(assoc_record) 2171 end 2172 end 2173 end 2174 end 2175 else 2176 opts[:dataset] ||= opts.association_dataset_proc 2177 opts[:eager_loader] ||= opts.method(:default_eager_loader) 2178 end 2179 2180 join_type = opts[:graph_join_type] 2181 select = opts[:graph_select] 2182 use_only_conditions = opts.include?(:graph_only_conditions) 2183 only_conditions = opts[:graph_only_conditions] 2184 conditions = opts[:graph_conditions] 2185 graph_block = opts[:graph_block] 2186 graph_jt_conds = opts[:graph_join_table_conditions] = opts.fetch(:graph_join_table_conditions, []).to_a 2187 use_jt_only_conditions = opts.include?(:graph_join_table_only_conditions) 2188 jt_only_conditions = opts[:graph_join_table_only_conditions] 2189 jt_join_type = opts[:graph_join_table_join_type] 2190 jt_graph_block = opts[:graph_join_table_block] 2191 opts[:eager_grapher] ||= proc do |eo| 2192 ds = eo[:self] 2193 egls = eo[:limit_strategy] 2194 if egls && egls != :ruby 2195 associated_key_array = opts.associated_key_array 2196 orig_egds = egds = eager_graph_dataset(opts, eo) 2197 egds = egds. 2198 inner_join(join_table, rcks.zip(opts.right_primary_keys) + graph_jt_conds, :qualify=>:deep). 2199 select_all(egds.first_source). 2200 select_append(*associated_key_array) 2201 egds = opts.apply_eager_graph_limit_strategy(egls, egds) 2202 ds.graph(egds, associated_key_array.map(&:alias).zip(lpkcs) + conditions, :qualify=>:deep, :table_alias=>eo[:table_alias], :implicit_qualifier=>eo[:implicit_qualifier], :join_type=>eo[:join_type]||join_type, :from_self_alias=>eo[:from_self_alias], :join_only=>eo[:join_only], :select=>select||orig_egds.columns, &graph_block) 2203 else 2204 ds = ds.graph(join_table, use_jt_only_conditions ? jt_only_conditions : lcks.zip(lpkcs) + graph_jt_conds, :select=>false, :table_alias=>ds.unused_table_alias(join_table, [eo[:table_alias]]), :join_type=>eo[:join_type]||jt_join_type, :join_only=>eo[:join_only], :implicit_qualifier=>eo[:implicit_qualifier], :qualify=>:deep, :from_self_alias=>eo[:from_self_alias], &jt_graph_block) 2205 ds.graph(eager_graph_dataset(opts, eo), use_only_conditions ? only_conditions : opts.right_primary_keys.zip(rcks) + conditions, :select=>select, :table_alias=>eo[:table_alias], :qualify=>:deep, :join_type=>eo[:join_type]||join_type, :join_only=>eo[:join_only], &graph_block) 2206 end 2207 end 2208 2209 return if opts[:read_only] 2210 2211 if one_through_one 2212 unless opts.has_key?(:setter) 2213 opts[:setter] = proc do |o| 2214 h = {} 2215 lh = lcks.zip(lcpks.map{|k| get_column_value(k)}) 2216 jtds = _join_table_dataset(opts).where(lh) 2217 2218 checked_transaction do 2219 current = jtds.first 2220 2221 if o 2222 new_values = [] 2223 rcks.zip(opts.right_primary_key_methods).each{|k, pk| new_values << (h[k] = o.get_column_value(pk))} 2224 end 2225 2226 if current 2227 current_values = rcks.map{|k| current[k]} 2228 jtds = jtds.where(rcks.zip(current_values)) 2229 if o 2230 if current_values != new_values 2231 jtds.update(h) 2232 end 2233 else 2234 jtds.delete 2235 end 2236 elsif o 2237 lh.each{|k,v| h[k] = v} 2238 jtds.insert(h) 2239 end 2240 end 2241 end 2242 end 2243 if opts.fetch(:setter, true) 2244 opts[:_setter] = proc{|o| set_one_through_one_associated_object(opts, o)} 2245 end 2246 else 2247 unless opts.has_key?(:adder) 2248 opts[:adder] = proc do |o| 2249 h = {} 2250 lcks.zip(lcpks).each{|k, pk| h[k] = get_column_value(pk)} 2251 rcks.zip(opts.right_primary_key_methods).each{|k, pk| h[k] = o.get_column_value(pk)} 2252 _join_table_dataset(opts).insert(h) 2253 end 2254 end 2255 2256 unless opts.has_key?(:remover) 2257 opts[:remover] = proc do |o| 2258 _join_table_dataset(opts).where(lcks.zip(lcpks.map{|k| get_column_value(k)}) + rcks.zip(opts.right_primary_key_methods.map{|k| o.get_column_value(k)})).delete 2259 end 2260 end 2261 2262 unless opts.has_key?(:clearer) 2263 opts[:clearer] = proc do 2264 _join_table_dataset(opts).where(lcks.zip(lcpks.map{|k| get_column_value(k)})).delete 2265 end 2266 end 2267 end 2268 end
Configures many_to_one
association reflection and adds the related association methods
# File lib/sequel/model/associations.rb 2271 def def_many_to_one(opts) 2272 name = opts[:name] 2273 opts[:key] = opts.default_key unless opts.has_key?(:key) 2274 key = opts[:key] 2275 opts[:eager_loader_key] = key unless opts.has_key?(:eager_loader_key) 2276 cks = opts[:graph_keys] = opts[:keys] = Array(key) 2277 opts[:key_column] ||= key 2278 opts[:graph_keys] = opts[:key_columns] = Array(opts[:key_column]) 2279 opts[:qualified_key] = opts.qualify_cur(key) 2280 if opts[:primary_key] 2281 cpks = Array(opts[:primary_key]) 2282 raise(Error, "mismatched number of keys: #{cks.inspect} vs #{cpks.inspect}") unless cks.length == cpks.length 2283 end 2284 uses_cks = opts[:uses_composite_keys] = cks.length > 1 2285 opts[:cartesian_product_number] ||= 0 2286 2287 if !opts.has_key?(:many_to_one_pk_lookup) && 2288 (opts[:dataset] || opts[:conditions] || opts[:block] || opts[:select] || 2289 (opts.has_key?(:key) && opts[:key] == nil)) 2290 opts[:many_to_one_pk_lookup] = false 2291 end 2292 auto_assocs = @autoreloading_associations 2293 cks.each do |k| 2294 (auto_assocs[k] ||= []) << name 2295 end 2296 2297 opts[:dataset] ||= opts.association_dataset_proc 2298 opts[:eager_loader] ||= proc do |eo| 2299 h = eo[:id_map] 2300 pk_meths = opts.primary_key_methods 2301 2302 eager_load_results(opts, eo) do |assoc_record| 2303 hash_key = uses_cks ? pk_meths.map{|k| assoc_record.get_column_value(k)} : assoc_record.get_column_value(opts.primary_key_method) 2304 h[hash_key].each{|object| object.associations[name] = assoc_record} 2305 end 2306 end 2307 2308 join_type = opts[:graph_join_type] 2309 select = opts[:graph_select] 2310 use_only_conditions = opts.include?(:graph_only_conditions) 2311 only_conditions = opts[:graph_only_conditions] 2312 conditions = opts[:graph_conditions] 2313 graph_block = opts[:graph_block] 2314 graph_cks = opts[:graph_keys] 2315 opts[:eager_grapher] ||= proc do |eo| 2316 ds = eo[:self] 2317 ds.graph(eager_graph_dataset(opts, eo), use_only_conditions ? only_conditions : opts.primary_keys.zip(graph_cks) + conditions, eo.merge(:select=>select, :join_type=>eo[:join_type]||join_type, :qualify=>:deep), &graph_block) 2318 end 2319 2320 return if opts[:read_only] 2321 2322 unless opts.has_key?(:setter) 2323 opts[:setter] = proc{|o| cks.zip(opts.primary_key_methods).each{|k, pk| set_column_value(:"#{k}=", (o.get_column_value(pk) if o))}} 2324 end 2325 if opts.fetch(:setter, true) 2326 opts[:_setter] = proc{|o| set_associated_object(opts, o)} 2327 end 2328 end
Alias of def_many_to_many
, since they share pretty much the same code.
# File lib/sequel/model/associations.rb 2452 def def_one_through_one(opts) 2453 def_many_to_many(opts) 2454 end
Configures one_to_many
and one_to_one
association reflections and adds the related association methods
# File lib/sequel/model/associations.rb 2331 def def_one_to_many(opts) 2332 one_to_one = opts[:type] == :one_to_one 2333 name = opts[:name] 2334 key = (opts[:key] ||= opts.default_key) 2335 km = opts[:key_method] ||= opts[:key] 2336 cks = opts[:keys] = Array(key) 2337 opts[:key_methods] = Array(opts[:key_method]) 2338 primary_key = (opts[:primary_key] ||= self.primary_key) 2339 opts[:eager_loader_key] = primary_key unless opts.has_key?(:eager_loader_key) 2340 cpks = opts[:primary_keys] = Array(primary_key) 2341 pkc = opts[:primary_key_column] ||= primary_key 2342 pkcs = opts[:primary_key_columns] ||= Array(pkc) 2343 raise(Error, "mismatched number of keys: #{cks.inspect} vs #{cpks.inspect}") unless cks.length == cpks.length 2344 uses_cks = opts[:uses_composite_keys] = cks.length > 1 2345 opts[:dataset] ||= opts.association_dataset_proc 2346 opts[:eager_loader] ||= proc do |eo| 2347 h = eo[:id_map] 2348 reciprocal = opts.reciprocal 2349 assign_singular = opts.assign_singular? 2350 delete_rn = opts.delete_row_number_column 2351 2352 eager_load_results(opts, eo) do |assoc_record| 2353 assoc_record.values.delete(delete_rn) if delete_rn 2354 hash_key = uses_cks ? km.map{|k| assoc_record.get_column_value(k)} : assoc_record.get_column_value(km) 2355 objects = h[hash_key] 2356 if assign_singular 2357 objects.each do |object| 2358 unless object.associations[name] 2359 object.associations[name] = assoc_record 2360 assoc_record.associations[reciprocal] = object if reciprocal 2361 end 2362 end 2363 else 2364 objects.each do |object| 2365 object.associations[name].push(assoc_record) 2366 assoc_record.associations[reciprocal] = object if reciprocal 2367 end 2368 end 2369 end 2370 end 2371 2372 join_type = opts[:graph_join_type] 2373 select = opts[:graph_select] 2374 use_only_conditions = opts.include?(:graph_only_conditions) 2375 only_conditions = opts[:graph_only_conditions] 2376 conditions = opts[:graph_conditions] 2377 opts[:cartesian_product_number] ||= one_to_one ? 0 : 1 2378 graph_block = opts[:graph_block] 2379 opts[:eager_grapher] ||= proc do |eo| 2380 ds = eo[:self] 2381 ds = ds.graph(opts.apply_eager_graph_limit_strategy(eo[:limit_strategy], eager_graph_dataset(opts, eo)), use_only_conditions ? only_conditions : cks.zip(pkcs) + conditions, eo.merge(:select=>select, :join_type=>eo[:join_type]||join_type, :qualify=>:deep), &graph_block) 2382 # We only load reciprocals for one_to_many associations, as other reciprocals don't make sense 2383 ds.opts[:eager_graph][:reciprocals][eo[:table_alias]] = opts.reciprocal 2384 ds 2385 end 2386 2387 return if opts[:read_only] 2388 2389 save_opts = {:validate=>opts[:validate]} 2390 ck_nil_hash ={} 2391 cks.each{|k| ck_nil_hash[k] = nil} 2392 2393 if one_to_one 2394 unless opts.has_key?(:setter) 2395 opts[:setter] = proc do |o| 2396 up_ds = _apply_association_options(opts, opts.associated_dataset.where(cks.zip(cpks.map{|k| get_column_value(k)}))) 2397 2398 if (froms = up_ds.opts[:from]) && (from = froms[0]) && (from.is_a?(Sequel::Dataset) || (from.is_a?(Sequel::SQL::AliasedExpression) && from.expression.is_a?(Sequel::Dataset))) 2399 if old = up_ds.first 2400 cks.each{|k| old.set_column_value(:"#{k}=", nil)} 2401 end 2402 save_old = true 2403 end 2404 2405 if o 2406 if !o.new? && !save_old 2407 up_ds = up_ds.exclude(o.pk_hash) 2408 end 2409 cks.zip(cpks).each{|k, pk| o.set_column_value(:"#{k}=", get_column_value(pk))} 2410 end 2411 2412 checked_transaction do 2413 if save_old 2414 old.save(save_opts) || raise(Sequel::Error, "invalid previously associated object, cannot save") if old 2415 else 2416 up_ds.skip_limit_check.update(ck_nil_hash) 2417 end 2418 2419 o.save(save_opts) || raise(Sequel::Error, "invalid associated object, cannot save") if o 2420 end 2421 end 2422 end 2423 if opts.fetch(:setter, true) 2424 opts[:_setter] = proc{|o| set_one_to_one_associated_object(opts, o)} 2425 end 2426 else 2427 save_opts[:raise_on_failure] = opts[:raise_on_save_failure] != false 2428 2429 unless opts.has_key?(:adder) 2430 opts[:adder] = proc do |o| 2431 cks.zip(cpks).each{|k, pk| o.set_column_value(:"#{k}=", get_column_value(pk))} 2432 o.save(save_opts) 2433 end 2434 end 2435 2436 unless opts.has_key?(:remover) 2437 opts[:remover] = proc do |o| 2438 cks.each{|k| o.set_column_value(:"#{k}=", nil)} 2439 o.save(save_opts) 2440 end 2441 end 2442 2443 unless opts.has_key?(:clearer) 2444 opts[:clearer] = proc do 2445 _apply_association_options(opts, opts.associated_dataset.where(cks.zip(cpks.map{|k| get_column_value(k)}))).update(ck_nil_hash) 2446 end 2447 end 2448 end 2449 end
Alias of def_one_to_many
, since they share pretty much the same code.
# File lib/sequel/model/associations.rb 2457 def def_one_to_one(opts) 2458 def_one_to_many(opts) 2459 end
Return dataset to graph into given the association reflection, applying the :callback option if set.
# File lib/sequel/model/associations.rb 2462 def eager_graph_dataset(opts, eager_options) 2463 ds = opts.associated_class.dataset 2464 if cb = eager_options[:callback] 2465 ds = cb.call(ds) 2466 end 2467 ds 2468 end
If not caching associations, reload the database schema by default, ignoring any cached values.
# File lib/sequel/model/associations.rb 2472 def reload_db_schema? 2473 !@cache_associations 2474 end