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 1610 def all_association_reflections 1611 association_reflections.values 1612 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. - :graph_use_association_block
-
Makes eager_graph consider the association block. Without this, eager_graph ignores the bock and only use the :graph_* options.
- :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 1849 def associate(type, name, opts = OPTS, &block) 1850 raise(Error, 'invalid association type') unless assoc_class = Sequel.synchronize{ASSOCIATION_TYPES[type]} 1851 raise(Error, 'Model.associate name argument must be a symbol') unless name.is_a?(Symbol) 1852 1853 # dup early so we don't modify opts 1854 orig_opts = opts.dup 1855 1856 if opts[:clone] 1857 cloned_assoc = association_reflection(opts[:clone]) 1858 remove_class_name = orig_opts[:class] && !orig_opts[:class_name] 1859 orig_opts = cloned_assoc[:orig_opts].merge(orig_opts) 1860 orig_opts.delete(:class_name) if remove_class_name 1861 end 1862 1863 opts = Hash[default_association_options] 1864 if type_options = default_association_type_options[type] 1865 opts.merge!(type_options) 1866 end 1867 opts.merge!(orig_opts) 1868 opts.merge!(:type => type, :name => name, :cache=>({} if cache_associations), :model => self) 1869 1870 opts[:block] = block if block 1871 opts[:instance_specific] = true if orig_opts[:dataset] 1872 if !opts.has_key?(:instance_specific) && (block || orig_opts[:block]) 1873 # It's possible the association is instance specific, in that it depends on 1874 # values other than the foreign key value. This needs to be checked for 1875 # in certain places to disable optimizations. 1876 opts[:instance_specific] = _association_instance_specific_default(name) 1877 end 1878 if (orig_opts[:instance_specific] || orig_opts[:dataset]) && !opts.has_key?(:allow_eager) && !opts[:eager_loader] 1879 # For associations explicitly marked as instance specific, or that use the 1880 # :dataset option, where :allow_eager is not set, and no :eager_loader is 1881 # provided, disallow eager loading. In these cases, eager loading is 1882 # unlikely to work. This is not done for implicit setting of :instance_specific, 1883 # because implicit use is done by default for all associations with blocks, 1884 # and the vast majority of associations with blocks use the block for filtering 1885 # in a manner compatible with eager loading. 1886 opts[:allow_eager] = false 1887 end 1888 opts = assoc_class.new.merge!(opts) 1889 1890 if opts[:clone] && !opts.cloneable?(cloned_assoc) 1891 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]})") 1892 end 1893 1894 opts[:use_placeholder_loader] = !opts[:instance_specific] && !opts[:eager_graph] 1895 opts[:eager_block] = opts[:block] unless opts.include?(:eager_block) 1896 opts[:graph_join_type] ||= :left_outer 1897 opts[:order_eager_graph] = true unless opts.include?(:order_eager_graph) 1898 conds = opts[:conditions] 1899 opts[:graph_alias_base] ||= name 1900 opts[:graph_conditions] = conds if !opts.include?(:graph_conditions) and Sequel.condition_specifier?(conds) 1901 opts[:graph_conditions] = opts.fetch(:graph_conditions, []).to_a 1902 opts[:graph_select] = Array(opts[:graph_select]) if opts[:graph_select] 1903 [:before_add, :before_remove, :after_add, :after_remove, :after_load, :before_set, :after_set].each do |cb_type| 1904 opts[cb_type] = Array(opts[cb_type]) if opts[cb_type] 1905 end 1906 1907 if opts[:extend] 1908 opts[:extend] = Array(opts[:extend]) 1909 opts[:reverse_extend] = opts[:extend].reverse 1910 end 1911 1912 late_binding_class_option(opts, opts.returns_array? ? singularize(name) : name) 1913 1914 # Remove :class entry if it exists and is nil, to work with cached_fetch 1915 opts.delete(:class) unless opts[:class] 1916 1917 def_association(opts) 1918 1919 orig_opts.delete(:clone) 1920 opts[:orig_class] = orig_opts[:class] || orig_opts[:class_name] 1921 orig_opts.merge!(:class_name=>opts[:class_name], :class=>opts[:class], :block=>opts[:block]) 1922 opts[:orig_opts] = orig_opts 1923 # don't add to association_reflections until we are sure there are no errors 1924 association_reflections[name] = opts 1925 end
The association reflection hash for the association of the given name.
# File lib/sequel/model/associations.rb 1928 def association_reflection(name) 1929 association_reflections[name] 1930 end
Array
of association name symbols
# File lib/sequel/model/associations.rb 1933 def associations 1934 association_reflections.keys 1935 end
Eager load the association with the given eager loader options.
# File lib/sequel/model/associations.rb 1938 def eager_load_results(opts, eo, &block) 1939 opts.eager_load_results(eo, &block) 1940 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 1957 def finalize_associations 1958 @association_reflections.each_value(&:finalize) 1959 end
Freeze association related metadata when freezing model class.
# File lib/sequel/model/associations.rb 1943 def freeze 1944 @association_reflections.freeze.each_value(&:freeze) 1945 @autoreloading_associations.freeze.each_value(&:freeze) 1946 @default_association_options.freeze 1947 @default_association_type_options.freeze 1948 @default_association_type_options.each_value(&:freeze) 1949 1950 super 1951 end
Shortcut for adding a many_to_many
association, see associate
# File lib/sequel/model/associations.rb 1962 def many_to_many(name, opts=OPTS, &block) 1963 associate(:many_to_many, name, opts, &block) 1964 end
Shortcut for adding a many_to_one
association, see associate
# File lib/sequel/model/associations.rb 1967 def many_to_one(name, opts=OPTS, &block) 1968 associate(:many_to_one, name, opts, &block) 1969 end
Shortcut for adding a one_through_one
association, see associate
# File lib/sequel/model/associations.rb 1972 def one_through_one(name, opts=OPTS, &block) 1973 associate(:one_through_one, name, opts, &block) 1974 end
Shortcut for adding a one_to_many
association, see associate
# File lib/sequel/model/associations.rb 1977 def one_to_many(name, opts=OPTS, &block) 1978 associate(:one_to_many, name, opts, &block) 1979 end
Shortcut for adding a one_to_one
association, see associate
# File lib/sequel/model/associations.rb 1982 def one_to_one(name, opts=OPTS, &block) 1983 associate(:one_to_one, name, opts, &block) 1984 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 1993 def _association_instance_specific_default(_) 1994 true 1995 end
The module to use for the association’s methods. Defaults to the overridable_methods_module.
# File lib/sequel/model/associations.rb 1999 def association_module(opts=OPTS) 2000 opts.fetch(:methods_module, overridable_methods_module) 2001 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 2006 def association_module_def(name, opts=OPTS, &block) 2007 mod = association_module(opts) 2008 mod.send(:define_method, name, &block) 2009 mod.send(:alias_method, name, name) 2010 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 2016 def association_module_delegate_def(name, opts, &block) 2017 mod = association_module(opts) 2018 mod.send(:define_method, name, &block) 2019 # :nocov: 2020 mod.send(:ruby2_keywords, name) if mod.respond_to?(:ruby2_keywords, true) 2021 # :nocov: 2022 mod.send(:alias_method, name, name) 2023 end
Add a private method to the module included in the class.
# File lib/sequel/model/associations.rb 2026 def association_module_private_def(name, opts=OPTS, &block) 2027 association_module_def(name, opts, &block) 2028 association_module(opts).send(:private, name) 2029 end
Delegate to the type-specific association method to setup the association, and define the association instance methods.
# File lib/sequel/model/associations.rb 2033 def def_association(opts) 2034 send(:"def_#{opts[:type]}", opts) 2035 def_association_instance_methods(opts) 2036 end
Define all of the association instance methods for this association.
# File lib/sequel/model/associations.rb 2046 def def_association_instance_methods(opts) 2047 # Always set the method names in the association reflection, even if they 2048 # are not used, for backwards compatibility. 2049 opts[:dataset_method] = :"#{opts[:name]}_dataset" 2050 if opts.returns_array? 2051 sname = singularize(opts[:name]) 2052 opts[:_add_method] = :"_add_#{sname}" 2053 opts[:add_method] = :"add_#{sname}" 2054 opts[:_remove_method] = :"_remove_#{sname}" 2055 opts[:remove_method] = :"remove_#{sname}" 2056 opts[:_remove_all_method] = :"_remove_all_#{opts[:name]}" 2057 opts[:remove_all_method] = :"remove_all_#{opts[:name]}" 2058 else 2059 opts[:_setter_method] = :"_#{opts[:name]}=" 2060 opts[:setter_method] = :"#{opts[:name]}=" 2061 end 2062 2063 association_module_def(opts.dataset_method, opts){_dataset(opts)} unless opts[:no_dataset_method] 2064 if opts[:block] 2065 opts[:block_method] = Plugins.def_sequel_method(association_module(opts), "#{opts[:name]}_block", 1, &opts[:block]) 2066 end 2067 opts[:dataset_opt_arity] = opts[:dataset].arity == 0 ? 0 : 1 2068 opts[:dataset_opt_method] = Plugins.def_sequel_method(association_module(opts), "#{opts[:name]}_dataset_opt", opts[:dataset_opt_arity], &opts[:dataset]) 2069 def_association_method(opts) unless opts[:no_association_method] 2070 2071 return if opts[:read_only] 2072 2073 if opts[:setter] && opts[:_setter] 2074 # This is backwards due to backwards compatibility 2075 association_module_private_def(opts[:_setter_method], opts, &opts[:setter]) 2076 association_module_def(opts[:setter_method], opts, &opts[:_setter]) 2077 end 2078 2079 if adder = opts[:adder] 2080 association_module_private_def(opts[:_add_method], opts, &adder) 2081 association_module_delegate_def(opts[:add_method], opts){|o,*args| add_associated_object(opts, o, *args)} 2082 end 2083 2084 if remover = opts[:remover] 2085 association_module_private_def(opts[:_remove_method], opts, &remover) 2086 association_module_delegate_def(opts[:remove_method], opts){|o,*args| remove_associated_object(opts, o, *args)} 2087 end 2088 2089 if clearer = opts[:clearer] 2090 association_module_private_def(opts[:_remove_all_method], opts, &clearer) 2091 association_module_delegate_def(opts[:remove_all_method], opts){|*args| remove_all_associated_objects(opts, *args)} 2092 end 2093 end
Adds the association method to the association methods module.
# File lib/sequel/model/associations.rb 2039 def def_association_method(opts) 2040 association_module_def(opts.association_method, opts) do |dynamic_opts=OPTS, &block| 2041 load_associated_objects(opts, dynamic_opts, &block) 2042 end 2043 end
Configures many_to_many
and one_through_one
association reflection and adds the related association methods
# File lib/sequel/model/associations.rb 2096 def def_many_to_many(opts) 2097 one_through_one = opts[:type] == :one_through_one 2098 left = (opts[:left_key] ||= opts.default_left_key) 2099 lcks = opts[:left_keys] = Array(left) 2100 right = (opts[:right_key] ||= opts.default_right_key) 2101 rcks = opts[:right_keys] = Array(right) 2102 left_pk = (opts[:left_primary_key] ||= self.primary_key) 2103 opts[:eager_loader_key] = left_pk unless opts.has_key?(:eager_loader_key) 2104 lcpks = opts[:left_primary_keys] = Array(left_pk) 2105 lpkc = opts[:left_primary_key_column] ||= left_pk 2106 lpkcs = opts[:left_primary_key_columns] ||= Array(lpkc) 2107 raise(Error, "mismatched number of left keys: #{lcks.inspect} vs #{lcpks.inspect}") unless lcks.length == lcpks.length 2108 if opts[:right_primary_key] 2109 rcpks = Array(opts[:right_primary_key]) 2110 raise(Error, "mismatched number of right keys: #{rcks.inspect} vs #{rcpks.inspect}") unless rcks.length == rcpks.length 2111 end 2112 opts[:uses_left_composite_keys] = lcks.length > 1 2113 uses_rcks = opts[:uses_right_composite_keys] = rcks.length > 1 2114 opts[:cartesian_product_number] ||= one_through_one ? 0 : 1 2115 join_table = (opts[:join_table] ||= opts.default_join_table) 2116 opts[:left_key_alias] ||= opts.default_associated_key_alias 2117 opts[:graph_join_table_join_type] ||= opts[:graph_join_type] 2118 if opts[:uniq] 2119 opts[:after_load] ||= [] 2120 opts[:after_load].unshift(:array_uniq!) 2121 end 2122 if join_table_db = opts[:join_table_db] 2123 opts[:use_placeholder_loader] = false 2124 opts[:allow_eager_graph] = false 2125 opts[:allow_filtering_by] = false 2126 opts[:eager_limit_strategy] = nil 2127 join_table_ds = join_table_db.from(join_table) 2128 opts[:dataset] ||= proc do |r| 2129 vals = join_table_ds.where(lcks.zip(lcpks.map{|k| get_column_value(k)})).select_map(right) 2130 ds = r.associated_dataset.where(opts.right_primary_key => vals) 2131 if uses_rcks 2132 vals.delete_if{|v| v.any?(&:nil?)} 2133 else 2134 vals.delete(nil) 2135 end 2136 ds = ds.clone(:no_results=>true) if vals.empty? 2137 ds 2138 end 2139 opts[:eager_loader] ||= proc do |eo| 2140 h = eo[:id_map] 2141 assign_singular = opts.assign_singular? 2142 rpk = opts.right_primary_key 2143 name = opts[:name] 2144 2145 join_map = join_table_ds.where(left=>h.keys).select_hash_groups(right, left) 2146 2147 if uses_rcks 2148 join_map.delete_if{|v,| v.any?(&:nil?)} 2149 else 2150 join_map.delete(nil) 2151 end 2152 2153 eo = Hash[eo] 2154 2155 if join_map.empty? 2156 eo[:no_results] = true 2157 else 2158 join_map.each_value do |vs| 2159 vs.replace(vs.flat_map{|v| h[v]}) 2160 vs.uniq! 2161 end 2162 2163 eo[:loader] = false 2164 eo[:right_keys] = join_map.keys 2165 end 2166 2167 opts[:model].eager_load_results(opts, eo) do |assoc_record| 2168 rpkv = if uses_rcks 2169 assoc_record.values.values_at(*rpk) 2170 else 2171 assoc_record.values[rpk] 2172 end 2173 2174 objects = join_map[rpkv] 2175 2176 if assign_singular 2177 objects.each do |object| 2178 object.associations[name] ||= assoc_record 2179 end 2180 else 2181 objects.each do |object| 2182 object.associations[name].push(assoc_record) 2183 end 2184 end 2185 end 2186 end 2187 else 2188 opts[:dataset] ||= opts.association_dataset_proc 2189 opts[:eager_loader] ||= opts.method(:default_eager_loader) 2190 end 2191 2192 join_type = opts[:graph_join_type] 2193 select = opts[:graph_select] 2194 use_only_conditions = opts.include?(:graph_only_conditions) 2195 only_conditions = opts[:graph_only_conditions] 2196 conditions = opts[:graph_conditions] 2197 graph_block = opts[:graph_block] 2198 graph_jt_conds = opts[:graph_join_table_conditions] = opts.fetch(:graph_join_table_conditions, []).to_a 2199 use_jt_only_conditions = opts.include?(:graph_join_table_only_conditions) 2200 jt_only_conditions = opts[:graph_join_table_only_conditions] 2201 jt_join_type = opts[:graph_join_table_join_type] 2202 jt_graph_block = opts[:graph_join_table_block] 2203 opts[:eager_grapher] ||= proc do |eo| 2204 ds = eo[:self] 2205 egls = eo[:limit_strategy] 2206 if egls && egls != :ruby 2207 associated_key_array = opts.associated_key_array 2208 orig_egds = egds = eager_graph_dataset(opts, eo) 2209 egds = egds. 2210 inner_join(join_table, rcks.zip(opts.right_primary_keys) + graph_jt_conds, :qualify=>:deep). 2211 select_all(egds.first_source). 2212 select_append(*associated_key_array) 2213 egds = opts.apply_eager_graph_limit_strategy(egls, egds) 2214 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) 2215 else 2216 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) 2217 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) 2218 end 2219 end 2220 2221 return if opts[:read_only] 2222 2223 if one_through_one 2224 unless opts.has_key?(:setter) 2225 opts[:setter] = proc do |o| 2226 h = {} 2227 lh = lcks.zip(lcpks.map{|k| get_column_value(k)}) 2228 jtds = _join_table_dataset(opts).where(lh) 2229 2230 checked_transaction do 2231 current = jtds.first 2232 2233 if o 2234 new_values = [] 2235 rcks.zip(opts.right_primary_key_methods).each{|k, pk| new_values << (h[k] = o.get_column_value(pk))} 2236 end 2237 2238 if current 2239 current_values = rcks.map{|k| current[k]} 2240 jtds = jtds.where(rcks.zip(current_values)) 2241 if o 2242 if current_values != new_values 2243 jtds.update(h) 2244 end 2245 else 2246 jtds.delete 2247 end 2248 elsif o 2249 lh.each{|k,v| h[k] = v} 2250 jtds.insert(h) 2251 end 2252 end 2253 end 2254 end 2255 if opts.fetch(:setter, true) 2256 opts[:_setter] = proc{|o| set_one_through_one_associated_object(opts, o)} 2257 end 2258 else 2259 unless opts.has_key?(:adder) 2260 opts[:adder] = proc do |o| 2261 h = {} 2262 lcks.zip(lcpks).each{|k, pk| h[k] = get_column_value(pk)} 2263 rcks.zip(opts.right_primary_key_methods).each{|k, pk| h[k] = o.get_column_value(pk)} 2264 _join_table_dataset(opts).insert(h) 2265 end 2266 end 2267 2268 unless opts.has_key?(:remover) 2269 opts[:remover] = proc do |o| 2270 _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 2271 end 2272 end 2273 2274 unless opts.has_key?(:clearer) 2275 opts[:clearer] = proc do 2276 _join_table_dataset(opts).where(lcks.zip(lcpks.map{|k| get_column_value(k)})).delete 2277 end 2278 end 2279 end 2280 end
Configures many_to_one
association reflection and adds the related association methods
# File lib/sequel/model/associations.rb 2283 def def_many_to_one(opts) 2284 name = opts[:name] 2285 opts[:key] = opts.default_key unless opts.has_key?(:key) 2286 key = opts[:key] 2287 opts[:eager_loader_key] = key unless opts.has_key?(:eager_loader_key) 2288 cks = opts[:graph_keys] = opts[:keys] = Array(key) 2289 opts[:key_column] ||= key 2290 opts[:graph_keys] = opts[:key_columns] = Array(opts[:key_column]) 2291 opts[:qualified_key] = opts.qualify_cur(key) 2292 if opts[:primary_key] 2293 cpks = Array(opts[:primary_key]) 2294 raise(Error, "mismatched number of keys: #{cks.inspect} vs #{cpks.inspect}") unless cks.length == cpks.length 2295 end 2296 uses_cks = opts[:uses_composite_keys] = cks.length > 1 2297 opts[:cartesian_product_number] ||= 0 2298 2299 if !opts.has_key?(:many_to_one_pk_lookup) && 2300 (opts[:dataset] || opts[:conditions] || opts[:block] || opts[:select] || 2301 (opts.has_key?(:key) && opts[:key] == nil)) 2302 opts[:many_to_one_pk_lookup] = false 2303 end 2304 auto_assocs = @autoreloading_associations 2305 cks.each do |k| 2306 (auto_assocs[k] ||= []) << name 2307 end 2308 2309 opts[:dataset] ||= opts.association_dataset_proc 2310 opts[:eager_loader] ||= proc do |eo| 2311 h = eo[:id_map] 2312 pk_meths = opts.primary_key_methods 2313 2314 eager_load_results(opts, eo) do |assoc_record| 2315 hash_key = uses_cks ? pk_meths.map{|k| assoc_record.get_column_value(k)} : assoc_record.get_column_value(opts.primary_key_method) 2316 h[hash_key].each{|object| object.associations[name] = assoc_record} 2317 end 2318 end 2319 2320 join_type = opts[:graph_join_type] 2321 select = opts[:graph_select] 2322 use_only_conditions = opts.include?(:graph_only_conditions) 2323 only_conditions = opts[:graph_only_conditions] 2324 conditions = opts[:graph_conditions] 2325 graph_block = opts[:graph_block] 2326 graph_cks = opts[:graph_keys] 2327 opts[:eager_grapher] ||= proc do |eo| 2328 ds = eo[:self] 2329 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) 2330 end 2331 2332 return if opts[:read_only] 2333 2334 unless opts.has_key?(:setter) 2335 opts[:setter] = proc{|o| cks.zip(opts.primary_key_methods).each{|k, pk| set_column_value(:"#{k}=", (o.get_column_value(pk) if o))}} 2336 end 2337 if opts.fetch(:setter, true) 2338 opts[:_setter] = proc{|o| set_associated_object(opts, o)} 2339 end 2340 end
Alias of def_many_to_many
, since they share pretty much the same code.
# File lib/sequel/model/associations.rb 2464 def def_one_through_one(opts) 2465 def_many_to_many(opts) 2466 end
Configures one_to_many
and one_to_one
association reflections and adds the related association methods
# File lib/sequel/model/associations.rb 2343 def def_one_to_many(opts) 2344 one_to_one = opts[:type] == :one_to_one 2345 name = opts[:name] 2346 key = (opts[:key] ||= opts.default_key) 2347 km = opts[:key_method] ||= opts[:key] 2348 cks = opts[:keys] = Array(key) 2349 opts[:key_methods] = Array(opts[:key_method]) 2350 primary_key = (opts[:primary_key] ||= self.primary_key) 2351 opts[:eager_loader_key] = primary_key unless opts.has_key?(:eager_loader_key) 2352 cpks = opts[:primary_keys] = Array(primary_key) 2353 pkc = opts[:primary_key_column] ||= primary_key 2354 pkcs = opts[:primary_key_columns] ||= Array(pkc) 2355 raise(Error, "mismatched number of keys: #{cks.inspect} vs #{cpks.inspect}") unless cks.length == cpks.length 2356 uses_cks = opts[:uses_composite_keys] = cks.length > 1 2357 opts[:dataset] ||= opts.association_dataset_proc 2358 opts[:eager_loader] ||= proc do |eo| 2359 h = eo[:id_map] 2360 reciprocal = opts.reciprocal 2361 assign_singular = opts.assign_singular? 2362 delete_rn = opts.delete_row_number_column 2363 2364 eager_load_results(opts, eo) do |assoc_record| 2365 assoc_record.values.delete(delete_rn) if delete_rn 2366 hash_key = uses_cks ? km.map{|k| assoc_record.get_column_value(k)} : assoc_record.get_column_value(km) 2367 objects = h[hash_key] 2368 if assign_singular 2369 objects.each do |object| 2370 unless object.associations[name] 2371 object.associations[name] = assoc_record 2372 assoc_record.associations[reciprocal] = object if reciprocal 2373 end 2374 end 2375 else 2376 objects.each do |object| 2377 object.associations[name].push(assoc_record) 2378 assoc_record.associations[reciprocal] = object if reciprocal 2379 end 2380 end 2381 end 2382 end 2383 2384 join_type = opts[:graph_join_type] 2385 select = opts[:graph_select] 2386 use_only_conditions = opts.include?(:graph_only_conditions) 2387 only_conditions = opts[:graph_only_conditions] 2388 conditions = opts[:graph_conditions] 2389 opts[:cartesian_product_number] ||= one_to_one ? 0 : 1 2390 graph_block = opts[:graph_block] 2391 opts[:eager_grapher] ||= proc do |eo| 2392 ds = eo[:self] 2393 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) 2394 # We only load reciprocals for one_to_many associations, as other reciprocals don't make sense 2395 ds.opts[:eager_graph][:reciprocals][eo[:table_alias]] = opts.reciprocal 2396 ds 2397 end 2398 2399 return if opts[:read_only] 2400 2401 save_opts = {:validate=>opts[:validate]} 2402 ck_nil_hash ={} 2403 cks.each{|k| ck_nil_hash[k] = nil} 2404 2405 if one_to_one 2406 unless opts.has_key?(:setter) 2407 opts[:setter] = proc do |o| 2408 up_ds = _apply_association_options(opts, opts.associated_dataset.where(cks.zip(cpks.map{|k| get_column_value(k)}))) 2409 2410 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))) 2411 if old = up_ds.first 2412 cks.each{|k| old.set_column_value(:"#{k}=", nil)} 2413 end 2414 save_old = true 2415 end 2416 2417 if o 2418 if !o.new? && !save_old 2419 up_ds = up_ds.exclude(o.pk_hash) 2420 end 2421 cks.zip(cpks).each{|k, pk| o.set_column_value(:"#{k}=", get_column_value(pk))} 2422 end 2423 2424 checked_transaction do 2425 if save_old 2426 old.save(save_opts) || raise(Sequel::Error, "invalid previously associated object, cannot save") if old 2427 else 2428 up_ds.skip_limit_check.update(ck_nil_hash) 2429 end 2430 2431 o.save(save_opts) || raise(Sequel::Error, "invalid associated object, cannot save") if o 2432 end 2433 end 2434 end 2435 if opts.fetch(:setter, true) 2436 opts[:_setter] = proc{|o| set_one_to_one_associated_object(opts, o)} 2437 end 2438 else 2439 save_opts[:raise_on_failure] = opts[:raise_on_save_failure] != false 2440 2441 unless opts.has_key?(:adder) 2442 opts[:adder] = proc do |o| 2443 cks.zip(cpks).each{|k, pk| o.set_column_value(:"#{k}=", get_column_value(pk))} 2444 o.save(save_opts) 2445 end 2446 end 2447 2448 unless opts.has_key?(:remover) 2449 opts[:remover] = proc do |o| 2450 cks.each{|k| o.set_column_value(:"#{k}=", nil)} 2451 o.save(save_opts) 2452 end 2453 end 2454 2455 unless opts.has_key?(:clearer) 2456 opts[:clearer] = proc do 2457 _apply_association_options(opts, opts.associated_dataset.where(cks.zip(cpks.map{|k| get_column_value(k)}))).update(ck_nil_hash) 2458 end 2459 end 2460 end 2461 end
Alias of def_one_to_many
, since they share pretty much the same code.
# File lib/sequel/model/associations.rb 2469 def def_one_to_one(opts) 2470 def_one_to_many(opts) 2471 end
Return dataset to graph into given the association reflection, applying the :callback option if set.
# File lib/sequel/model/associations.rb 2474 def eager_graph_dataset(opts, eager_options) 2475 ds = opts.associated_class.dataset 2476 if opts[:graph_use_association_block] && (b = opts[:block]) 2477 ds = b.call(ds) 2478 end 2479 if cb = eager_options[:callback] 2480 ds = cb.call(ds) 2481 end 2482 ds 2483 end
If not caching associations, reload the database schema by default, ignoring any cached values.
# File lib/sequel/model/associations.rb 2487 def reload_db_schema? 2488 !@cache_associations 2489 end