Class: ActiveRecord::Associations::JoinDependency::JoinAssociation

Inherits:
JoinPart
  • Object
show all
Defined in:
lib/active_record/associations/join_dependency/join_association.rb

Overview

:nodoc:

Instance Attribute Summary collapse

Attributes inherited from JoinPart

#base_klass, #children

Instance Method Summary collapse

Methods inherited from JoinPart

#each, #each_children, #extract_record, #instantiate

Constructor Details

#initialize(reflection, children) ⇒ JoinAssociation

Returns a new instance of JoinAssociation.



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# File 'lib/active_record/associations/join_dependency/join_association.rb', line 13

def initialize(reflection, children)
  super(reflection.klass, children)

  @reflection = reflection
end

Instance Attribute Details

#reflectionObject (readonly)

Returns the value of attribute reflection.



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# File 'lib/active_record/associations/join_dependency/join_association.rb', line 10

def reflection
  @reflection
end

#tableObject

Returns the value of attribute table.



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# File 'lib/active_record/associations/join_dependency/join_association.rb', line 11

def table
  @table
end

#tablesObject (readonly)

Returns the value of attribute tables.



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# File 'lib/active_record/associations/join_dependency/join_association.rb', line 10

def tables
  @tables
end

Instance Method Details

#join_constraints(foreign_table, foreign_klass, join_type, alias_tracker) ⇒ Object



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# File 'lib/active_record/associations/join_dependency/join_association.rb', line 24

def join_constraints(foreign_table, foreign_klass, join_type, alias_tracker)
  joins = []
  chain = []

  reflection.chain.each do |reflection|
    table, terminated = yield reflection
    @table ||= table

    if terminated
      foreign_table, foreign_klass = table, reflection.klass
      break
    end

    chain << [reflection, table]
  end

  # 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 do |reflection, table|
    klass = reflection.klass

    scope = reflection.join_scope(table, foreign_table, foreign_klass)

    unless scope.references_values.empty?
      associations = scope.eager_load_values | scope.includes_values

      unless associations.empty?
        scope.joins! scope.construct_join_dependency(associations, Arel::Nodes::OuterJoin)
      end
    end

    arel = scope.arel(alias_tracker.aliases)
    nodes = arel.constraints.first

    if nodes.is_a?(Arel::Nodes::And)
      others = nodes.children.extract! do |node|
        !Arel.fetch_attribute(node) { |attr| attr.relation.name == table.name }
      end
    end

    joins << join_type.new(table, Arel::Nodes::On.new(nodes))

    if others && !others.empty?
      joins.concat arel.join_sources
      append_constraints(joins.last, others)
    end

    # The current table in this iteration becomes the foreign table in the next
    foreign_table, foreign_klass = table, klass
  end

  joins
end

#match?(other) ⇒ Boolean

Returns:

  • (Boolean)


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# File 'lib/active_record/associations/join_dependency/join_association.rb', line 19

def match?(other)
  return true if self == other
  super && reflection == other.reflection
end

#readonly?Boolean

Returns:

  • (Boolean)


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# File 'lib/active_record/associations/join_dependency/join_association.rb', line 78

def readonly?
  return @readonly if defined?(@readonly)

  @readonly = reflection.scope && reflection.scope_for(base_klass.unscoped).readonly_value
end

#strict_loading?Boolean

Returns:

  • (Boolean)


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# File 'lib/active_record/associations/join_dependency/join_association.rb', line 84

def strict_loading?
  return @strict_loading if defined?(@strict_loading)

  @strict_loading = reflection.scope && reflection.scope_for(base_klass.unscoped).strict_loading_value
end