Class: Lutaml::Model::MappingRule

Inherits:
Object
  • Object
show all
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.



46
47
48
49
50
51
52
53
54
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
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 46

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
  @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.



4
5
6
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 4

def as_attribute
  @as_attribute
end

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

Returns the value of attribute attribute.



4
5
6
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 4

def attribute
  @attribute
end

#custom_methods ⇒ Object (readonly)

Returns the value of attribute custom_methods.



4
5
6
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 4

def custom_methods
  @custom_methods
end

#delegate ⇒ Object (readonly)

Returns the value of attribute delegate.



4
5
6
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 4

def delegate
  @delegate
end

#format ⇒ Object (readonly)

Returns the value of attribute format.



4
5
6
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 4

def format
  @format
end

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

Returns the value of attribute name.



4
5
6
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 4

def name
  @name
end

#polymorphic ⇒ Object (readonly)

Returns the value of attribute polymorphic.



4
5
6
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 4

def polymorphic
  @polymorphic
end

#polymorphic_map ⇒ Object (readonly)

Returns the value of attribute polymorphic_map.



4
5
6
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 4

def polymorphic_map
  @polymorphic_map
end

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

Returns the value of attribute render_default.



4
5
6
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 4

def render_default
  @render_default
end

#render_empty ⇒ Object (readonly)

Returns the value of attribute render_empty.



4
5
6
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 4

def render_empty
  @render_empty
end

#render_nil ⇒ Object (readonly)

Returns the value of attribute render_nil.



4
5
6
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 4

def render_nil
  @render_nil
end

#to ⇒ Object (readonly)

Returns the value of attribute to.



4
5
6
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 4

def to
  @to
end

#to_instance ⇒ Object (readonly)

Returns the value of attribute to_instance.



4
5
6
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 4

def to_instance
  @to_instance
end

#transform ⇒ Object (readonly)

Returns the value of attribute transform.



4
5
6
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 4

def transform
  @transform
end

#treat_empty ⇒ Object (readonly)

Returns the value of attribute treat_empty.



4
5
6
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 4

def treat_empty
  @treat_empty
end

#treat_nil ⇒ Object (readonly)

Returns the value of attribute treat_nil.



4
5
6
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 4

def treat_nil
  @treat_nil
end

#treat_omitted ⇒ Object (readonly)

Returns the value of attribute treat_omitted.



4
5
6
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 4

def treat_omitted
  @treat_omitted
end

Instance Method Details

#can_transform_to?(attribute, format) ⇒ Boolean

Returns:

  • (Boolean) 


372
373
374
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 372

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

#deep_dup ⇒ Object

Raises:

  • (NotImplementedError) 


320
321
322
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 320

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

#default_value_map(options = {}) ⇒ Object 



115
116
117
118
119
120
121
122
123
124
125
126
127
128
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 115

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) ⇒ Object 



286
287
288
289
290
291
292
293
294
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 286

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

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

Returns:

  • (Boolean) 


312
313
314
315
316
317
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 312

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 



379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 379

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:

  • (Boolean) 


300
301
302
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 300

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

#has_custom_method_for_serialization? ⇒ Boolean

Returns:

  • (Boolean) 


296
297
298
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 296

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:

  • (Boolean) 


207
208
209
210
211
212
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 207

def has_items?(value)
  return false if value.nil? || Utils.uninitialized?(value)
  return false unless value.respond_to?(:empty?)

  !value.empty?
end

#multiple_mappings? ⇒ Boolean

Returns:

  • (Boolean) 


304
305
306
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 304

def multiple_mappings?
  name.is_a?(Array)
end

#mutated_collection?(value, instance) ⇒ Boolean

Returns:

  • (Boolean) 


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

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.respond_to?(:using_default?) && instance.using_default?(to)
end

#polymorphic_mapping? ⇒ Boolean

Returns:

  • (Boolean) 


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

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

#raw_mapping? ⇒ Boolean

Returns:

  • (Boolean) 


308
309
310
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 308

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.



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

def raw_value_map
  @value_map
end

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

Returns:

  • (Boolean) 


158
159
160
161
162
163
164
165
166
167
168
169
170
171
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 158

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.respond_to?(:using_default?) && instance.using_default?(to)
    render_default? || RenderPolicy.derived_attribute_for?(instance, to)
  else
    true
  end
end

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



130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 130

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:

  • (Boolean) 


225
226
227
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 225

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

#render_nil?(options = {}) ⇒ Boolean

Returns:

  • (Boolean) 


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

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

#render_omitted?(options = {}) ⇒ Boolean

Returns:

  • (Boolean) 


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

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

#render_value_for(value) ⇒ Object 



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

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) ⇒ Object 



265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 265

def serialize(model, parent = nil, doc = nil)
  if custom_methods[:to]
    model.send(custom_methods[:to], model, parent, doc)
  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

#serialize_attribute(model, element, doc) ⇒ Object 



249
250
251
252
253
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 249

def serialize_attribute(model, element, doc)
  if custom_methods[:to]
    model.send(custom_methods[:to], model, element, doc)
  end
end

#to_value_for(model) ⇒ Object 



255
256
257
258
259
260
261
262
263
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 255

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 



347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 347

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:

  • (Boolean) 


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

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 



150
151
152
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 150

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

#treat_empty?(options = {}) ⇒ Boolean

Returns:

  • (Boolean) 


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

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

#treat_nil?(options = {}) ⇒ Boolean

Returns:

  • (Boolean) 


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

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

#treat_omitted?(options = {}) ⇒ Boolean

Returns:

  • (Boolean) 


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

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

#value_for_option(option, empty_value = nil) ⇒ Object 



214
215
216
217
218
219
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 214

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 



330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
 
# File 'lib/lutaml/model/mapping/mapping_rule.rb', line 330

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