Class: Lutaml::Model::MappingRule

Inherits:
Object
  • Object
show all
Includes:
DeepDupable
Defined in:
lib/lutaml/model/mapping/mapping_rule.rb

Direct Known Subclasses

KeyValue::MappingRule, Xml::MappingRule

Constant Summary collapse

ALLOWED_OPTIONS = 
{
  render_nil: i[
    omit
    as_nil
    as_blank
    as_empty
  ],
  render_empty: i[
    omit
    as_empty
    as_blank
    as_nil
  ],
}.freeze
EMPTY_TRANSFORMERS =

Frozen empty array for the common case of no transformers

[].freeze

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(name, to:, to_instance: nil, as_attribute: nil, render_nil: false, render_default: false, render_empty: false, treat_nil: :nil, treat_empty: :empty, treat_omitted: :nil, with: {}, attribute: false, delegate: nil, root_mappings: nil, polymorphic: {}, polymorphic_map: {}, transform: {}, value_map: {}) ⇒ MappingRule

Returns a new instance of MappingRule.



55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 55

def initialize(
  name,
  to:,
  to_instance: nil,
  as_attribute: nil,
  render_nil: false,
  render_default: false,
  render_empty: false,
  treat_nil: :nil,
  treat_empty: :empty,
  treat_omitted: :nil,
  with: {},
  attribute: false,
  delegate: nil,
  root_mappings: nil,
  polymorphic: {},
  polymorphic_map: {},
  transform: {},
  value_map: {}
)
  @name = name
  @to = to
  # Dynamic symbol built per call allocated ~10% of parse objects on
  # attribute-heavy documents; `to` is immutable, so build it once.
  @setter_name = :"#{to}="
  @to_instance = to_instance
  @as_attribute = as_attribute
  @render_nil = render_nil
  @render_default = render_default
  @render_empty = render_empty
  @treat_nil = treat_nil
  @treat_empty = treat_empty
  @treat_omitted = treat_omitted
  @custom_methods = with
  @attribute = attribute
  @delegate = delegate
  @root_mappings = root_mappings
  @polymorphic = polymorphic
  @polymorphic_map = polymorphic_map
  @transform = transform

  # Cache whether this rule needs the full deserialize chain.
  # Over 95% of rules are "simple" (no custom method, no delegate).
  @needs_full_deserialize = has_custom_method_for_deserialization? || !!delegate

  # Only calculate default_value_map if value_map is not fully provided
  if value_map.empty? || !value_map[:from] || !value_map[:to]
    # Build value_map by starting with defaults from render_nil/render_empty,
    # then overlaying user-provided value_map entries on top.
    # User-provided value_map entries take PRECEDENCE over computed defaults.
    # This ensures that value_map: { to: { empty: :empty } } overrides
    # the default render_empty: false → :omitted behavior.
    vm = {
      from: (value_map[:from] || {}).dup,
      to: (value_map[:to] || {}).dup,
    }
    defaults = default_value_map
    vm[:from] = defaults[:from].merge(vm[:from])
    vm[:to] = defaults[:to].merge(vm[:to])
    @value_map = vm
  else
    # Complete value_map provided (e.g., from deep_dup), use it directly.
    @value_map = value_map
  end

  # Freeze value_map and its inner hashes — they are never mutated after
  # construction, and downstream code reads them on every serialization.
  @value_map[:from].freeze
  @value_map[:to].freeze
  @value_map.freeze
end

Instance Attribute Details

#as_attribute ⇒ Object (readonly)

Returns the value of attribute as_attribute.



6
7
8
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 6

def as_attribute
  @as_attribute
end

#attribute ⇒ Object (readonly) Also known as: attribute?

Returns the value of attribute attribute.



6
7
8
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 6

def attribute
  @attribute
end

#custom_methods ⇒ Object (readonly)

Returns the value of attribute custom_methods.



6
7
8
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 6

def custom_methods
  @custom_methods
end

#delegate ⇒ Object (readonly)

Returns the value of attribute delegate.



6
7
8
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 6

def delegate
  @delegate
end

#format ⇒ Object (readonly)

Returns the value of attribute format.



6
7
8
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 6

def format
  @format
end

#name ⇒ Object (readonly) Also known as: from

Returns the value of attribute name.



6
7
8
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 6

def name
  @name
end

#polymorphic ⇒ Object (readonly)

Returns the value of attribute polymorphic.



6
7
8
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 6

def polymorphic
  @polymorphic
end

#polymorphic_map ⇒ Object (readonly)

Returns the value of attribute polymorphic_map.



6
7
8
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 6

def polymorphic_map
  @polymorphic_map
end

#render_default ⇒ Object (readonly) Also known as: render_default?

Returns the value of attribute render_default.



6
7
8
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 6

def render_default
  @render_default
end

#render_empty ⇒ Object (readonly)

Returns the value of attribute render_empty.



6
7
8
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 6

def render_empty
  @render_empty
end

#render_nil ⇒ Object (readonly)

Returns the value of attribute render_nil.



6
7
8
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 6

def render_nil
  @render_nil
end

#to ⇒ Object (readonly)

Returns the value of attribute to.



6
7
8
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 6

def to
  @to
end

#to_instance ⇒ Object (readonly)

Returns the value of attribute to_instance.



6
7
8
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 6

def to_instance
  @to_instance
end

#transform ⇒ Object (readonly)

Returns the value of attribute transform.



6
7
8
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 6

def transform
  @transform
end

#treat_empty ⇒ Object (readonly)

Returns the value of attribute treat_empty.



6
7
8
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 6

def treat_empty
  @treat_empty
end

#treat_nil ⇒ Object (readonly)

Returns the value of attribute treat_nil.



6
7
8
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 6

def treat_nil
  @treat_nil
end

#treat_omitted ⇒ Object (readonly)

Returns the value of attribute treat_omitted.



6
7
8
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 6

def treat_omitted
  @treat_omitted
end

Instance Method Details

#can_transform_to?(attribute, format) ⇒ Boolean

Returns:



398
399
400
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 398

def can_transform_to?(attribute, format)
  get_transformers(attribute).any? { |t| t.can_transform?(:to, format) }
end

#custom_method_only? ⇒ Boolean

Static per rule: placeholder __name__ targets and inferred custom-method targets without an attribute type never change — the applier asked this per element and paid two to_s strings each time (240k allocations on the ISO-13849 serialize profile). Rules may be frozen, so no per-instance memo: one to_s instead of two is the frozen-safe diet.

Returns:



316
317
318
319
320
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 316

def custom_method_only?
  name = attribute_name.to_s
  (name.start_with?("__") && name.end_with?("__")) ||
    (has_custom_methods? && attribute_type.nil?)
end

#deep_dup ⇒ Object

Raises:



346
347
348
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 346

def deep_dup
  raise NotImplementedError, "Subclasses must implement `deep_dup`."
end

#default_value_map(options = {}) ⇒ Object 



127
128
129
130
131
132
133
134
135
136
137
138
139
140
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 127

def default_value_map(options = {})
  render_nil_as = render_as(:render_nil, :omitted, options)
  render_empty_as = render_as(:render_empty, :empty, options)

  treat_nil_as = treat_as(:treat_nil, :nil, options)
  treat_empty_as = treat_as(:treat_empty, :empty, options)
  treat_omitted_as = treat_as(:treat_omitted, :nil, options)

  {
    from: { omitted: treat_omitted_as, nil: treat_nil_as,
            empty: treat_empty_as },
    to: { omitted: :omitted, nil: render_nil_as, empty: render_empty_as },
  }
end

#deserialize(model, value, attributes, mapper_class = nil, context = nil) ⇒ Object 



299
300
301
302
303
304
305
306
307
308
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 299

def deserialize(model, value, attributes, mapper_class = nil,
context = nil)
  if @needs_full_deserialize
    handle_custom_method(model, value, mapper_class, context) ||
      handle_delegate(model, value, attributes) ||
      handle_transform_method(model, value, attributes, context)
  else
    handle_transform_method(model, value, attributes, context)
  end
end

#eql?(other) ⇒ Boolean Also known as: ==

Returns:



338
339
340
341
342
343
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 338

def eql?(other)
  other.class == self.class &&
    instance_variables.all? do |var|
      instance_variable_get(var) == other.instance_variable_get(var)
    end
end

#get_transformers(attribute) ⇒ Object 



405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 405

def get_transformers(attribute)
  # Fast path: most rules have no transforms at all
  rule_transform = transform
  attr_transform = attribute&.transform

  if !rule_transform && !attr_transform
    return EMPTY_TRANSFORMERS
  end

  # Build transformer list only when needed
  transformers = []
  transformers << rule_transform if rule_transform
  transformers << attr_transform if attr_transform
  transformers.select! { |t| t.is_a?(Class) }
  transformers.freeze
end

#has_custom_method_for_deserialization? ⇒ Boolean

Returns:



326
327
328
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 326

def has_custom_method_for_deserialization?
  !custom_methods.empty? && custom_methods[:from]
end

#has_custom_method_for_serialization? ⇒ Boolean

Returns:



322
323
324
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 322

def has_custom_method_for_serialization?
  !custom_methods.empty? && custom_methods[:to]
end

#has_items?(value) ⇒ Boolean

Check if value is a non-empty collection

Returns:



219
220
221
222
223
224
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 219

def has_items?(value)
  return false if value.nil? || Utils.uninitialized?(value)
  return false unless value.is_a?(String) || value.is_a?(Array) || value.is_a?(Hash)

  !value.empty?
end

#multiple_mappings? ⇒ Boolean

Returns:



330
331
332
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 330

def multiple_mappings?
  name.is_a?(Array)
end

#mutated_collection?(value, instance) ⇒ Boolean

Returns:



209
210
211
212
213
214
215
216
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 209

def mutated_collection?(value, instance)
  return false if value.nil? || Utils.uninitialized?(value)
  return false unless value.is_a?(Array) || value.is_a?(Lutaml::Model::Collection)
  return false if value.empty? # Empty collection is still default

  # If it's a non-empty collection and marked as using_default, it was mutated
  instance.is_a?(Lutaml::Model::Serialize) && instance.using_default?(to)
end

#name_strings ⇒ Object

Normalized name spellings for matching, computed once. The name is fixed after construction (attr_reader only), so the memo is safe. Hot loops used to redo Array(name).map(&:to_s) per element.



51
52
53
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 51

def name_strings
  @name_strings ||= Array(name).map(&:to_s).freeze
end

#polymorphic_mapping? ⇒ Boolean

Returns:



257
258
259
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 257

def polymorphic_mapping?
  polymorphic_map && !polymorphic_map.empty?
end

#raw_mapping? ⇒ Boolean

Returns:



334
335
336
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 334

def raw_mapping?
  name == Constants::RAW_MAPPING_KEY
end

#raw_value_map ⇒ Object

Raw value_map hash access (for compiled rules). Use value_map(key, options) for individual lookups with overrides.



352
353
354
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 352

def raw_value_map
  @value_map
end

#render?(value, instance = nil, options = {}) ⇒ Boolean

Returns:



170
171
172
173
174
175
176
177
178
179
180
181
182
183
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 170

def render?(value, instance = nil, options = {})
  if invalid_value?(value, options)
    false
  # FIXED: Check if collection was mutated after initialization
  # A non-empty collection initialized with default [] should render if mutated
  # This handles the case where collection is mutated with << or custom methods
  elsif mutated_collection?(value, instance)
    true
  elsif instance.is_a?(Lutaml::Model::Serialize) && instance.using_default?(to)
    render_default? || RenderPolicy.derived_attribute_for?(instance, to)
  else
    true
  end
end

#render_as(key, default_value, options = {}) ⇒ Object 



142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 142

def render_as(key, default_value, options = {})
  value = public_send(key)
  value = options[key] if value.nil?

  if value == true
    key.to_s.split("_").last.to_sym
  elsif value == false
    :omitted
  elsif value
    {
      as_empty: :empty,
      as_blank: :blank,
      as_nil: :nil,
      omit: :omitted,
    }[value]
  else
    default_value
  end
end

#render_empty?(options = {}) ⇒ Boolean

Returns:



237
238
239
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 237

def render_empty?(options = {})
  value_map(:to, options)[:empty] != :omitted
end

#render_nil?(options = {}) ⇒ Boolean

Returns:



233
234
235
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 233

def render_nil?(options = {})
  value_map(:to, options)[:nil] != :omitted
end

#render_omitted?(options = {}) ⇒ Boolean

Returns:



241
242
243
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 241

def render_omitted?(options = {})
  value_map(:to, options)[:omitted] != :omitted
end

#render_value_for(value) ⇒ Object 



197
198
199
200
201
202
203
204
205
206
207
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 197

def render_value_for(value)
  if value.nil?
    value_for_option(value_map(:to)[:nil])
  elsif Utils.empty?(value)
    value_for_option(value_map(:to)[:empty], value)
  elsif Utils.uninitialized?(value)
    value_for_option(value_map(:to)[:omitted])
  else
    value
  end
end

#serialize(model, parent = nil, doc = nil, context = nil) ⇒ Object 



271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 271

def serialize(model, parent = nil, doc = nil, context = nil)
  if custom_methods[:to]
    to_method = custom_methods[:to]
    # lutaml-model#550: custom methods may declare a fourth
    # context parameter to receive the options passed to `to_*`.
    if model.method(to_method).parameters.size >= 4
      model.public_send(to_method, model, parent, doc, context)
    else
      model.public_send(to_method, model, parent, doc)
    end
  else
    value = to_value_for(model)

    # Handle Reference types - extract the key for serialization
    # This ensures references serialize as their key, not the resolved object
    if value.is_a?(Lutaml::Model::Type::Reference)
      value = value.key
    elsif value.is_a?(Array)
      # Handle collection of references
      value = value.map do |v|
        v.is_a?(Lutaml::Model::Type::Reference) ? v.key : v
      end
    end

    value
  end
end

#to_value_for(model) ⇒ Object 



261
262
263
264
265
266
267
268
269
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 261

def to_value_for(model)
  if delegate
    model.public_send(delegate).public_send(to)
  else
    return if to.nil?

    model.public_send(to)
  end
end

#transform_value(attribute, value, read_method, format) ⇒ Object 



373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 373

def transform_value(attribute, value, read_method, format)
  # Fast path: no transforms at all (covers 95%+ of rules)
  # transform defaults to {}, so check for actual content, not just truthiness
  has_rule_transform = transform.is_a?(Class)
  has_attr_transform = attribute&.transform.is_a?(Class)
  return value unless has_rule_transform || has_attr_transform

  transformers = get_transformers(attribute)
  transformers = transformers.reverse if read_method == :to

  return value if transformers.empty? || transformers.none? do |t|
    t.can_transform?(read_method, format)
  end

  # Apply transformers in sequence
  transformers.reduce(value) do |v, transformer|
    if transformer.is_a?(Class) && transformer < Lutaml::Model::ValueTransformer
      # Call class method directly: NameTransformer.from(value, :json)
    else
      # Hash/proc transformer
    end
    transformer.public_send(read_method, v, format)
  end
end

#treat?(value) ⇒ Boolean

Returns:



185
186
187
188
189
190
191
192
193
194
195
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 185

def treat?(value)
  if value.nil?
    treat_nil?
  elsif Utils.uninitialized?(value)
    treat_omitted?
  elsif Utils.empty?(value)
    treat_empty?
  else
    true
  end
end

#treat_as(key, default_value, options = {}) ⇒ Object 



162
163
164
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 162

def treat_as(key, default_value, options = {})
  public_send(key) || options[key] || default_value
end

#treat_empty?(options = {}) ⇒ Boolean

Returns:



249
250
251
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 249

def treat_empty?(options = {})
  value_map(:from, options)[:empty] != :omitted
end

#treat_nil?(options = {}) ⇒ Boolean

Returns:



245
246
247
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 245

def treat_nil?(options = {})
  value_map(:from, options)[:nil] != :omitted
end

#treat_omitted?(options = {}) ⇒ Boolean

Returns:



253
254
255
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 253

def treat_omitted?(options = {})
  value_map(:from, options)[:omitted] != :omitted
end

#value_for_option(option, empty_value = nil) ⇒ Object 



226
227
228
229
230
231
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 226

def value_for_option(option, empty_value = nil)
  return nil if option == :nil
  return empty_value || "" if option == :empty

  Lutaml::Model::UninitializedClass.instance
end

#value_map(key, options = {}) ⇒ Object 



356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 356

def value_map(key, options = {})
  # Fast path: when no overrides, return cached value directly
  # Callers MUST NOT mutate the returned hash
  if !options[:nil] && !options[:empty] && !options[:omitted]
    return @value_map[key]
  end

  # Slow path: merge overrides (only when options have actual values)
  overrides = {
    nil: options[:nil],
    empty: options[:empty],
    omitted: options[:omitted],
  }.compact

  @value_map[key].merge(overrides)
end