Class: ActiveRecord::Associations::ClassMethods::JoinDependency::JoinPart

Inherits:

Object

• Object
• ActiveRecord::Associations::ClassMethods::JoinDependency::JoinPart

show all

Defined in:

activerecord/lib/active_record/associations/class_methods/join_dependency/join_part.rb

Overview

Instance Attribute Summary (collapse)

• - (Object) active_record readonly

  The Active Record class which this join part is associated 'about'; for a JoinBase this is the actual base model, for a JoinAssociation this is the target model of the association.

Instance Method Summary (collapse)

• - (Object) ==(other)
• - (Object) aliased_prefix

  The prefix to be used when aliasing columns in the active_record's table.

• - (Object) aliased_primary_key

  The alias for the primary key of the active_record's table.

• - (Object) aliased_table
• - (Object) aliased_table_name

  The alias for the active_record's table.

• - (Object) column_names_with_alias

  An array of [column_name, alias] pairs for the table.

• - (Object) extract_record(row)
• - (JoinPart) initialize(active_record) constructor

  A new instance of JoinPart.

• - (Object) instantiate(row)
• - (Object) record_id(row)
• - (Object) table

  An Arel::Table for the active_record.

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# File 'activerecord/lib/active_record/associations/class_methods/join_dependency/join_part.rb', line 19

def initialize(active_record)
  @active_record = active_record
  @cached_record = {}
  @column_names_with_alias = nil
end

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# File 'activerecord/lib/active_record/associations/class_methods/join_dependency/join_part.rb', line 15

def active_record
  @active_record
end

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# File 'activerecord/lib/active_record/associations/class_methods/join_dependency/join_part.rb', line 29

def ==(other)
  raise NotImplementedError
end

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# File 'activerecord/lib/active_record/associations/class_methods/join_dependency/join_part.rb', line 39

def aliased_prefix
  raise NotImplementedError
end

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# File 'activerecord/lib/active_record/associations/class_methods/join_dependency/join_part.rb', line 49

def aliased_primary_key
  "#{aliased_prefix}_r0"
end

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# File 'activerecord/lib/active_record/associations/class_methods/join_dependency/join_part.rb', line 25

def aliased_table
  Arel::Nodes::TableAlias.new aliased_table_name, table
end

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# File 'activerecord/lib/active_record/associations/class_methods/join_dependency/join_part.rb', line 44

def aliased_table_name
  raise NotImplementedError
end

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# File 'activerecord/lib/active_record/associations/class_methods/join_dependency/join_part.rb', line 54

def column_names_with_alias
  unless @column_names_with_alias
    @column_names_with_alias = []

    ([primary_key] + (column_names - [primary_key])).each_with_index do |column_name, i|
      @column_names_with_alias << [column_name, "#{aliased_prefix}_r#{i}"]
    end
  end
  @column_names_with_alias
end

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# File 'activerecord/lib/active_record/associations/class_methods/join_dependency/join_part.rb', line 65

def extract_record(row)
  Hash[column_names_with_alias.map{|cn, an| [cn, row[an]]}]
end

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# File 'activerecord/lib/active_record/associations/class_methods/join_dependency/join_part.rb', line 73

def instantiate(row)
  @cached_record[record_id(row)] ||= active_record.send(:instantiate, extract_record(row))
end

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# File 'activerecord/lib/active_record/associations/class_methods/join_dependency/join_part.rb', line 69

def record_id(row)
  row[aliased_primary_key]
end

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# File 'activerecord/lib/active_record/associations/class_methods/join_dependency/join_part.rb', line 34

def table
  raise NotImplementedError
end