diff options
Diffstat (limited to 'activerecord/lib/active_record/associations/join_dependency/join_association.rb')
| -rw-r--r-- | activerecord/lib/active_record/associations/join_dependency/join_association.rb | 267 |
1 files changed, 66 insertions, 201 deletions
diff --git a/activerecord/lib/active_record/associations/join_dependency/join_association.rb b/activerecord/lib/active_record/associations/join_dependency/join_association.rb index ebe39c35fe..4121a5b378 100644 --- a/activerecord/lib/active_record/associations/join_dependency/join_association.rb +++ b/activerecord/lib/active_record/associations/join_dependency/join_association.rb @@ -2,6 +2,8 @@ module ActiveRecord module Associations class JoinDependency # :nodoc: class JoinAssociation < JoinPart # :nodoc: + include JoinHelper + # The reflection of the association represented attr_reader :reflection @@ -18,10 +20,15 @@ module ActiveRecord attr_accessor :join_type # These implement abstract methods from the superclass - attr_reader :aliased_prefix, :aliased_table_name + attr_reader :aliased_prefix + + attr_reader :tables - delegate :options, :through_reflection, :source_reflection, :to => :reflection + delegate :options, :through_reflection, :source_reflection, :chain, :to => :reflection delegate :table, :table_name, :to => :parent, :prefix => :parent + delegate :alias_tracker, :to => :join_dependency + + alias :alias_suffix :parent_table_name def initialize(reflection, join_dependency, parent = nil) reflection.check_validity! @@ -37,14 +44,7 @@ module ActiveRecord @parent = parent @join_type = Arel::InnerJoin @aliased_prefix = "t#{ join_dependency.join_parts.size }" - - # This must be done eagerly upon initialisation because the alias which is produced - # depends on the state of the join dependency, but we want it to work the same way - # every time. - allocate_aliases - @table = Arel::Table.new( - table_name, :as => aliased_table_name, :engine => arel_engine - ) + @tables = construct_tables.reverse end def ==(other) @@ -60,219 +60,84 @@ module ActiveRecord end def join_to(relation) - send("join_#{reflection.macro}_to", relation) - end - - def join_relation(joining_relation) - self.join_type = Arel::OuterJoin - joining_relation.joins(self) - end - - attr_reader :table - # More semantic name given we are talking about associations - alias_method :target_table, :table - - protected - - def aliased_table_name_for(name, suffix = nil) - aliases = @join_dependency.table_aliases - - if aliases[name] != 0 # We need an alias - connection = active_record.connection - - name = connection.table_alias_for "#{pluralize(reflection.name)}_#{parent_table_name}#{suffix}" - aliases[name] += 1 - name = name[0, connection.table_alias_length-3] + "_#{aliases[name]}" if aliases[name] > 1 - else - aliases[name] += 1 - end - - name - end + tables = @tables.dup + foreign_table = parent_table + + # The chain starts with the target table, but we want to end with it here (makes + # more sense in this context), so we reverse + chain.reverse.each_with_index do |reflection, i| + table = tables.shift + + case reflection.source_macro + when :belongs_to + key = reflection.association_primary_key + foreign_key = reflection.foreign_key + when :has_and_belongs_to_many + # Join the join table first... + relation.from(join( + table, + table[reflection.foreign_key]. + eq(foreign_table[reflection.active_record_primary_key]) + )) + + foreign_table, table = table, tables.shift + + key = reflection.association_primary_key + foreign_key = reflection.association_foreign_key + else + key = reflection.foreign_key + foreign_key = reflection.active_record_primary_key + end - def pluralize(table_name) - ActiveRecord::Base.pluralize_table_names ? table_name.to_s.pluralize : table_name - end + constraint = table[key].eq(foreign_table[foreign_key]) - private + if reflection.klass.finder_needs_type_condition? + constraint = table.create_and([ + constraint, + reflection.klass.send(:type_condition, table) + ]) + end - def allocate_aliases - @aliased_table_name = aliased_table_name_for(table_name) + relation.from(join(table, constraint)) - if reflection.macro == :has_and_belongs_to_many - @aliased_join_table_name = aliased_table_name_for(reflection.options[:join_table], "_join") - elsif [:has_many, :has_one].include?(reflection.macro) && reflection.options[:through] - @aliased_join_table_name = aliased_table_name_for(reflection.through_reflection.klass.table_name, "_join") - end - end + unless conditions[i].empty? + relation.where(sanitize(conditions[i], table)) + end - def process_conditions(conditions, table_name) - if conditions.respond_to?(:to_proc) - conditions = instance_eval(&conditions) + # The current table in this iteration becomes the foreign table in the next + foreign_table = table end - Arel.sql(sanitize_sql(conditions, table_name)) + relation end - def sanitize_sql(condition, table_name) - active_record.send(:sanitize_sql, condition, table_name) + def join_relation(joining_relation) + self.join_type = Arel::OuterJoin + joining_relation.joins(self) end - def join_target_table(relation, condition) - conditions = [condition] - - # If the target table is an STI model then we must be sure to only include records of - # its type and its sub-types. - unless active_record.descends_from_active_record? - sti_column = target_table[active_record.inheritance_column] - subclasses = active_record.descendants - sti_condition = sti_column.eq(active_record.sti_name) - - conditions << subclasses.inject(sti_condition) { |attr,subclass| - attr.or(sti_column.eq(subclass.sti_name)) - } - end - - # If the reflection has conditions, add them - if options[:conditions] - conditions << process_conditions(options[:conditions], aliased_table_name) - end - - ands = relation.create_and(conditions) - - join = relation.create_join( - target_table, - relation.create_on(ands), - join_type) - - relation.from join + def table + tables.last end - def join_has_and_belongs_to_many_to(relation) - join_table = Arel::Table.new( - options[:join_table] - ).alias(@aliased_join_table_name) - - fk = options[:foreign_key] || reflection.active_record.to_s.foreign_key - klass_fk = options[:association_foreign_key] || reflection.klass.to_s.foreign_key - - relation = relation.join(join_table, join_type) - relation = relation.on( - join_table[fk]. - eq(parent_table[reflection.active_record.primary_key]) - ) - - join_target_table( - relation, - target_table[reflection.klass.primary_key]. - eq(join_table[klass_fk]) - ) + def aliased_table_name + table.table_alias || table.name end - def join_has_many_to(relation) - if reflection.options[:through] - join_has_many_through_to(relation) - elsif reflection.options[:as] - join_has_many_polymorphic_to(relation) - else - foreign_key = options[:foreign_key] || reflection.active_record.name.foreign_key - primary_key = options[:primary_key] || parent.primary_key - - join_target_table( - relation, - target_table[foreign_key]. - eq(parent_table[primary_key]) - ) - end + def conditions + @conditions ||= reflection.conditions.reverse end - alias :join_has_one_to :join_has_many_to - - def join_has_many_through_to(relation) - join_table = Arel::Table.new( - through_reflection.klass.table_name - ).alias @aliased_join_table_name - jt_conditions = [] - first_key = second_key = nil + private - if through_reflection.macro == :belongs_to - jt_primary_key = through_reflection.foreign_key - jt_foreign_key = through_reflection.association_primary_key + def interpolate(conditions) + if conditions.respond_to?(:to_proc) + instance_eval(&conditions) else - jt_primary_key = through_reflection.active_record_primary_key - jt_foreign_key = through_reflection.foreign_key - - if through_reflection.options[:as] # has_many :through against a polymorphic join - jt_conditions << - join_table["#{through_reflection.options[:as]}_type"]. - eq(parent.active_record.base_class.name) - end + conditions end - - case source_reflection.macro - when :has_many - second_key = options[:foreign_key] || primary_key - - if source_reflection.options[:as] - first_key = "#{source_reflection.options[:as]}_id" - else - first_key = through_reflection.klass.base_class.to_s.foreign_key - end - - unless through_reflection.klass.descends_from_active_record? - jt_conditions << - join_table[through_reflection.active_record.inheritance_column]. - eq(through_reflection.klass.sti_name) - end - when :belongs_to - first_key = primary_key - - if reflection.options[:source_type] - second_key = source_reflection.association_foreign_key - - jt_conditions << - join_table[reflection.source_reflection.foreign_type]. - eq(reflection.options[:source_type]) - else - second_key = source_reflection.foreign_key - end - end - - jt_conditions << - parent_table[jt_primary_key]. - eq(join_table[jt_foreign_key]) - - if through_reflection.options[:conditions] - jt_conditions << process_conditions(through_reflection.options[:conditions], aliased_table_name) - end - - relation = relation.join(join_table, join_type).on(*jt_conditions) - - join_target_table( - relation, - target_table[first_key].eq(join_table[second_key]) - ) end - def join_has_many_polymorphic_to(relation) - join_target_table( - relation, - target_table["#{reflection.options[:as]}_id"]. - eq(parent_table[parent.primary_key]).and( - target_table["#{reflection.options[:as]}_type"]. - eq(parent.active_record.base_class.name)) - ) - end - - def join_belongs_to_to(relation) - foreign_key = options[:foreign_key] || reflection.foreign_key - primary_key = options[:primary_key] || reflection.klass.primary_key - - join_target_table( - relation, - target_table[primary_key].eq(parent_table[foreign_key]) - ) - end end end end |