Class: YamlExporter::Nodes::ManyReference

Inherits:
Object
  • Object
show all
Includes:
OfResolution
Defined in:
lib/yaml_exporter/nodes/many_reference.rb

Overview

many :assoc, find_by: :column — standalone reference list (HABTM or has_many). No block, no entry attributes: each YAML string resolves to an existing target record via find_by. Target records are never created or mutated; only the association is updated.

With of: the value is resolved indirectly through a 1:[0,1] association on the target (see OfResolution), so the YAML lists the find_by value of a related model (e.g. the user slug behind each target) rather than a column on the target itself.

Phase: :post_save (join rows / FK need parent.id).

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods included from OfResolution

#find_target_via, #of_class, #of_reflection, #of_value_for, #resolve_target_by_of, #singular_of_association?, #validate_of_reflection!

Constructor Details

#initialize(name:, owner_class:, find_by:, of: nil) ⇒ ManyReference

Returns a new instance of ManyReference.



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# File 'lib/yaml_exporter/nodes/many_reference.rb', line 21

def initialize(name:, owner_class:, find_by:, of: nil)
  @name = name.to_sym
  @owner_class = owner_class
  @find_by = find_by.to_sym
  @of = of&.to_sym
  reflection = owner_class.reflect_on_association(@name)
  unless reflection
    raise ArgumentError,
          "`many #{name.inspect}`: #{owner_class} has no association `#{name}`"
  end

  validate_of_reflection!("many #{name.inspect}") if @of
end

Instance Attribute Details

#find_by ⇒ Object (readonly)

Returns the value of attribute find_by.



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# File 'lib/yaml_exporter/nodes/many_reference.rb', line 19

def find_by
  @find_by
end

#name ⇒ Object (readonly)

Returns the value of attribute name.



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# File 'lib/yaml_exporter/nodes/many_reference.rb', line 19

def name
  @name
end

#of ⇒ Object (readonly)

Returns the value of attribute of.



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# File 'lib/yaml_exporter/nodes/many_reference.rb', line 19

def of
  @of
end

#owner_class ⇒ Object (readonly)

Returns the value of attribute owner_class.



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# File 'lib/yaml_exporter/nodes/many_reference.rb', line 19

def owner_class
  @owner_class
end

Instance Method Details

#export(record, exporter:) ⇒ Object 



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# File 'lib/yaml_exporter/nodes/many_reference.rb', line 64

def export(record, exporter:)
  targets = Array(record.public_send(@name))
  keys = targets.map { |t| key_for(t) }.compact.sort
  [@name.to_s, keys]
end

#import(record, data, path:, importer:) ⇒ Object 



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# File 'lib/yaml_exporter/nodes/many_reference.rb', line 47

def import(record, data, path:, importer:)
  raw = data.key?(@name.to_s) ? data[@name.to_s] : nil
  values = Array(raw)

  unless values.all? { |v| v.is_a?(String) || v.is_a?(Symbol) || v.is_a?(Numeric) }
    raise UnknownAttributeError,
          "#{describe_path(path)}: expected a list of #{@find_by} values, got #{raw.inspect}"
  end

  targets = values.map do |value|
    resolve_target(value) ||
      (raise ActiveRecord::RecordNotFound, not_found_message(value))
  end

  record.public_send("#{@name}=", targets)
end

#phase ⇒ Object 



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# File 'lib/yaml_exporter/nodes/many_reference.rb', line 35

def phase
  :post_save
end

#schema_fragment ⇒ Object 



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# File 'lib/yaml_exporter/nodes/many_reference.rb', line 70

def schema_fragment
  key_class = @of ? of_class : target_class
  item_type = TypeInference.schema_type_for(key_class, @find_by)
  { @name => { type: 'array', items: { type: item_type } } }
end

#target_class ⇒ Object 



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# File 'lib/yaml_exporter/nodes/many_reference.rb', line 43

def target_class
  @target_class ||= @owner_class.reflect_on_association(@name).klass
end

#yaml_keys ⇒ Object 



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# File 'lib/yaml_exporter/nodes/many_reference.rb', line 39

def yaml_keys
  [@name.to_s]
end