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authorAaron Patterson <aaron.patterson@gmail.com>2010-11-23 17:34:18 -0800
committerAaron Patterson <aaron.patterson@gmail.com>2010-11-23 17:42:49 -0800
commit1aaa8edeb958a263c7a256344f442867c4b90c5f (patch)
treecfd3e19cd2eabb4558317013495f0c2bb35d375f /activerecord/lib/active_record/associations/class_methods/join_dependency.rb
parenta551d2ec62f205a755d3b760a9943f20addafe35 (diff)
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breaking classes up in to respective files
Diffstat (limited to 'activerecord/lib/active_record/associations/class_methods/join_dependency.rb')
-rw-r--r--activerecord/lib/active_record/associations/class_methods/join_dependency.rb216
1 files changed, 216 insertions, 0 deletions
diff --git a/activerecord/lib/active_record/associations/class_methods/join_dependency.rb b/activerecord/lib/active_record/associations/class_methods/join_dependency.rb
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+++ b/activerecord/lib/active_record/associations/class_methods/join_dependency.rb
@@ -0,0 +1,216 @@
+require 'active_record/associations/class_methods/join_dependency/join_part'
+require 'active_record/associations/class_methods/join_dependency/join_base'
+require 'active_record/associations/class_methods/join_dependency/join_association'
+
+module ActiveRecord
+ module Associations
+ module ClassMethods
+ class JoinDependency # :nodoc:
+ attr_reader :join_parts, :reflections, :table_aliases
+
+ def initialize(base, associations, joins)
+ @join_parts = [JoinBase.new(base, joins)]
+ @associations = {}
+ @reflections = []
+ @table_aliases = Hash.new(0)
+ @table_aliases[base.table_name] = 1
+ build(associations)
+ end
+
+ def graft(*associations)
+ associations.each do |association|
+ join_associations.detect {|a| association == a} ||
+ build(association.reflection.name, association.find_parent_in(self) || join_base, association.join_type)
+ end
+ self
+ end
+
+ def join_associations
+ join_parts.last(join_parts.length - 1)
+ end
+
+ def join_base
+ join_parts.first
+ end
+
+ def count_aliases_from_table_joins(name)
+ # quoted_name should be downcased as some database adapters (Oracle) return quoted name in uppercase
+ quoted_name = join_base.active_record.connection.quote_table_name(name.downcase).downcase
+ join_sql = join_base.table_joins.to_s.downcase
+ join_sql.blank? ? 0 :
+ # Table names
+ join_sql.scan(/join(?:\s+\w+)?\s+#{quoted_name}\son/).size +
+ # Table aliases
+ join_sql.scan(/join(?:\s+\w+)?\s+\S+\s+#{quoted_name}\son/).size
+ end
+
+ def instantiate(rows)
+ primary_key = join_base.aliased_primary_key
+ parents = {}
+
+ records = rows.map { |model|
+ primary_id = model[primary_key]
+ parent = parents[primary_id] ||= join_base.instantiate(model)
+ construct(parent, @associations, join_associations.dup, model)
+ parent
+ }.uniq
+
+ remove_duplicate_results!(join_base.active_record, records, @associations)
+ records
+ end
+
+ def remove_duplicate_results!(base, records, associations)
+ case associations
+ when Symbol, String
+ reflection = base.reflections[associations]
+ remove_uniq_by_reflection(reflection, records)
+ when Array
+ associations.each do |association|
+ remove_duplicate_results!(base, records, association)
+ end
+ when Hash
+ associations.keys.each do |name|
+ reflection = base.reflections[name]
+ remove_uniq_by_reflection(reflection, records)
+
+ parent_records = []
+ records.each do |record|
+ if descendant = record.send(reflection.name)
+ if reflection.collection?
+ parent_records.concat descendant.target.uniq
+ else
+ parent_records << descendant
+ end
+ end
+ end
+
+ remove_duplicate_results!(reflection.klass, parent_records, associations[name]) unless parent_records.empty?
+ end
+ end
+ end
+
+ protected
+
+ def cache_joined_association(association)
+ associations = []
+ parent = association.parent
+ while parent != join_base
+ associations.unshift(parent.reflection.name)
+ parent = parent.parent
+ end
+ ref = @associations
+ associations.each do |key|
+ ref = ref[key]
+ end
+ ref[association.reflection.name] ||= {}
+ end
+
+ def build(associations, parent = nil, join_type = Arel::InnerJoin)
+ parent ||= join_parts.last
+ case associations
+ when Symbol, String
+ reflection = parent.reflections[associations.to_s.intern] or
+ raise ConfigurationError, "Association named '#{ associations }' was not found; perhaps you misspelled it?"
+ unless join_association = find_join_association(reflection, parent)
+ @reflections << reflection
+ join_association = build_join_association(reflection, parent)
+ join_association.join_type = join_type
+ @join_parts << join_association
+ cache_joined_association(join_association)
+ end
+ join_association
+ when Array
+ associations.each do |association|
+ build(association, parent, join_type)
+ end
+ when Hash
+ associations.keys.sort{|a,b|a.to_s<=>b.to_s}.each do |name|
+ join_association = build(name, parent, join_type)
+ build(associations[name], join_association, join_type)
+ end
+ else
+ raise ConfigurationError, associations.inspect
+ end
+ end
+
+ def find_join_association(name_or_reflection, parent)
+ if String === name_or_reflection
+ name_or_reflection = name_or_reflection.to_sym
+ end
+
+ join_associations.detect { |j|
+ j.reflection == name_or_reflection && j.parent == parent
+ }
+ end
+
+ def remove_uniq_by_reflection(reflection, records)
+ if reflection && reflection.collection?
+ records.each { |record| record.send(reflection.name).target.uniq! }
+ end
+ end
+
+ def build_join_association(reflection, parent)
+ JoinAssociation.new(reflection, self, parent)
+ end
+
+ def construct(parent, associations, join_parts, row)
+ case associations
+ when Symbol, String
+ name = associations.to_s
+
+ join_part = join_parts.detect { |j|
+ j.reflection.name.to_s == name &&
+ j.parent_table_name == parent.class.table_name }
+
+ raise(ConfigurationError, "No such association") unless join_part
+
+ join_parts.delete(join_part)
+ construct_association(parent, join_part, row)
+ when Array
+ associations.each do |association|
+ construct(parent, association, join_parts, row)
+ end
+ when Hash
+ associations.sort_by { |k,_| k.to_s }.each do |name, assoc|
+ association = construct(parent, name, join_parts, row)
+ construct(association, assoc, join_parts, row) if association
+ end
+ else
+ raise ConfigurationError, associations.inspect
+ end
+ end
+
+ def construct_association(record, join_part, row)
+ return if record.id.to_s != join_part.parent.record_id(row).to_s
+
+ macro = join_part.reflection.macro
+ if macro == :has_one
+ return if record.instance_variable_defined?("@#{join_part.reflection.name}")
+ association = join_part.instantiate(row) unless row[join_part.aliased_primary_key].nil?
+ set_target_and_inverse(join_part, association, record)
+ else
+ return if row[join_part.aliased_primary_key].nil?
+ association = join_part.instantiate(row)
+ case macro
+ when :has_many, :has_and_belongs_to_many
+ collection = record.send(join_part.reflection.name)
+ collection.loaded
+ collection.target.push(association)
+ collection.__send__(:set_inverse_instance, association, record)
+ when :belongs_to
+ set_target_and_inverse(join_part, association, record)
+ else
+ raise ConfigurationError, "unknown macro: #{join_part.reflection.macro}"
+ end
+ end
+ association
+ end
+
+ def set_target_and_inverse(join_part, association, record)
+ association_proxy = record.send("set_#{join_part.reflection.name}_target", association)
+ association_proxy.__send__(:set_inverse_instance, association, record)
+ end
+ end
+ end
+ end
+end