Module: Lutaml::Model::Serialize::FormatConversion

Included in:
ClassMethods
Defined in:
lib/lutaml/model/serialize/format_conversion.rb

Overview

Handles format conversion methods for Serialize::ClassMethods

Extracted from serialize.rb to improve code organization. Provides methods for serializing/deserializing between formats.

Instance Method Summary collapse

Instance Method Details

#array_passthrough_format?(format) ⇒ Boolean

Whether this format+model combination requires the parsed array to pass through to the transformer as a whole (not split per element). YAMLS with sequence definitions needs the full document array.

Parameters:

  • format (Symbol) —

    The format

Returns:

  • (Boolean) 


165
166
167
168
169
170
171
172
173
174
 
# File 'lib/lutaml/model/serialize/format_conversion.rb', line 165

def array_passthrough_format?(format)
  return true if format == :jsonl

  if format == :yamls
    mapping = mappings[format]
    return true if mapping.respond_to?(:yamls_sequence) && mapping.yamls_sequence
  end

  false
end

#as(format, instance, options = {}) ⇒ Object

Convert a model instance to format-specific data structure

Parameters:

  • format (Symbol) —

    The format

  • instance (Object) —

    The model instance

  • options (Hash) (defaults to: {}) —

    Additional options

Returns:

  • (Object) —

    The format-specific data structure



225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
 
# File 'lib/lutaml/model/serialize/format_conversion.rb', line 225

def as(format, instance, options = {})
  if instance.is_a?(Array)
    return instance.map { |item| public_send(:"as_#{format}", item) }
  end

  unless instance.is_a?(model)
    msg = "argument is a '#{instance.class}' but should be a '#{model}'"
    raise Lutaml::Model::IncorrectModelError, msg
  end

  # Resolve imports at the start of serialization
  register = options[:register] || Lutaml::Model::Config.default_register

  # Hook for format-specific pre-serialization (e.g., XML mapping import resolution)
  pre_serialize_hook(format, register)

  # Recursively resolve child model imports
  ensure_child_imports_resolved!(register)

  transformer = Lutaml::Model::Config.transformer_for(format)
  transformer.model_to_data(self, instance, format, options)
end

#default_mappings(format) ⇒ Mapping

Generate default mappings for a format

Parameters:

  • format (Symbol) —

    The format

Returns:

  • (Mapping) —

    The default mapping



300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
 
# File 'lib/lutaml/model/serialize/format_conversion.rb', line 300

def default_mappings(format)
  klass = ::Lutaml::Model::Config.mappings_class_for(format)
  mappings = klass.new

  mappings.tap do |mapping|
    attributes&.each_key do |name|
      mapping.map_element(
        name.to_s,
        to: name,
      )
    end

    # DO NOT auto-generate root element for XML
    # Models without an explicit xml block should be type-only models
    # If a root element is needed, declare it explicitly in xml block
  end
end

#format_error_types ⇒ Array<Class>

Get list of error types that can be raised during format parsing. Core errors are always included; format-specific errors come from FormatRegistry registrations.

Performance: Cached base types + lazy TOML lookup. Tomlib::ParseError is lazily loaded, so we check for it on each call rather than caching a stale nil reference.

Returns:

  • (Array<Class>) —

    List of error classes



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
 
# File 'lib/lutaml/model/serialize/format_conversion.rb', line 83

def format_error_types
  @format_error_types_base ||= begin
    errors = [
      Lutaml::Model::RuntimeCompatibility.safe_constantize("Psych::SyntaxError"),
      Lutaml::Model::RuntimeCompatibility.safe_constantize("JSON::ParserError"),
      NoMethodError,
      TypeError,
      ArgumentError,
    ]

    # Collect format-specific error types from FormatRegistry
    compatibility = Lutaml::Model::RuntimeCompatibility
    FormatRegistry.all.each_value do |info|
      next unless info[:error_types]

      info[:error_types].each do |error_class|
        cls = if error_class.is_a?(String)
                compatibility.safe_constantize(error_class)
              else
                error_class
              end
        errors << cls
      end
    end

    errors.compact.freeze
  end

  # Legacy TOML error types are lazy, so check them on each call.
  compatibility = Lutaml::Model::RuntimeCompatibility
  toml_errors = compatibility.safe_constantize("TomlRB::ParseError")
  toml_errors = Array(toml_errors)
  tomllib_err = compatibility.safe_constantize("Tomlib::ParseError")
  toml_errors << tomllib_err if tomllib_err

  @format_error_types_base + toml_errors
end

#from(format, data, options = {}) ⇒ Object

Deserialize from a format

Parameters:

  • format (Symbol) —

    The format to deserialize from

  • data (String, Object) —

    The data to deserialize

  • options (Hash) (defaults to: {}) —

    Additional options

Returns:

  • (Object) —

    The deserialized model instance



42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
 
# File 'lib/lutaml/model/serialize/format_conversion.rb', line 42

def from(format, data, options = {})
  Instrumentation.instrument(:from, model: name, format: format) do
    adapter = resolve_adapter(format, options.delete(:adapter))

    raise Lutaml::Model::FormatAdapterNotSpecifiedError.new(format) if adapter.nil?

    # Resolve imports at the entry point of deserialization
    register = options[:register] || Lutaml::Model::Config.default_register

    # Hook for format-specific pre-deserialization (e.g., XML mapping import resolution)
    pre_deserialize_hook(format, register)

    # Recursively resolve child model imports
    # This ensures the entire model tree is finalized before parsing
    ensure_child_imports_resolved!(register)

    doc = adapter.parse(data, options)
    send("of_#{format}", doc, options)
  end
rescue *format_error_types => e
  raise Lutaml::Model::InvalidFormatError.new(format, e.message)
end

#key_value(&block) ⇒ Object

Define key-value mappings for multiple formats. Uses FormatRegistry to discover key-value formats dynamically, falling back to Config::KEY_VALUE_FORMATS for bootstrap.

Parameters:

  • block (Proc) —

    The DSL block



262
263
264
265
266
267
268
269
270
271
272
273
274
 
# File 'lib/lutaml/model/serialize/format_conversion.rb', line 262

def key_value(&block)
  formats = if FormatRegistry.formats.any?
              FormatRegistry.key_value_formats
            else
              Lutaml::Model::Config::KEY_VALUE_FORMATS
            end

  formats.each do |format|
    mappings[format] ||= Lutaml::KeyValue::Mapping.new(format)
    mappings[format].instance_eval(&block)
    mappings[format].finalize(self)
  end
end

#mappings_for(format, register = nil) ⇒ Mapping?

Get resolved mapping for a format

Delegates to TransformationRegistry for centralized caching (Single Source of Truth - Phase 11.5).

Register resolution: If the caller passes a parent register (e.g., :default) but this class declares its own ‘lutaml_default_register`, the child’s register takes precedence. This ensures mappings are resolved in the correct context for cross-register embedding.

Parameters:

  • format (Symbol) —

    The format (:xml, :json, :yaml, :toml, :hash)

  • register (Symbol, Register, nil) (defaults to: nil) —

    The register for import resolution

Returns:

  • (Mapping, nil) —

    The resolved mapping or nil



289
290
291
292
293
294
 
# File 'lib/lutaml/model/serialize/format_conversion.rb', line 289

def mappings_for(format, register = nil)
  resolved_register = Lutaml::Model::Register.resolve_for_child(self,
                                                                register)
  TransformationRegistry.instance.get_or_build_mapping(self, format,
                                                       resolved_register)
end

#of(format, doc, options = {}) ⇒ Object

Create a model instance from a parsed document

Parameters:

  • format (Symbol) —

    The format

  • doc (Object) —

    The parsed document

  • options (Hash) (defaults to: {}) —

    Additional options

Returns:

  • (Object) —

    The model instance



132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
 
# File 'lib/lutaml/model/serialize/format_conversion.rb', line 132

def of(format, doc, options = {})
  if doc.is_a?(Array) && !array_passthrough_format?(format)
    return doc.map { |item| send(:"of_#{format}", item) }
  end

  register = extract_register_id(options[:register])

  # Hook for format-specific document validation (e.g., XML root/encoding/doctype)
  validate_document(format, doc, options, register)

  options[:register] = register

  transformer = Lutaml::Model::Config.transformer_for(format)
  transformer.data_to_model(self, doc, format, options)
end

#post_process_mapping(_format) ⇒ Object

Hook for format-specific post-processing after mapping DSL evaluation. XML overrides this to call check_sort_configs!.

Parameters:

  • _format (Symbol) —

    The format



32
33
34
 
# File 'lib/lutaml/model/serialize/format_conversion.rb', line 32

def post_process_mapping(_format)
  # No-op by default; XML overrides via prepend
end

#pre_deserialize_hook(_format, _register) ⇒ Object

Hook for format-specific pre-deserialization logic. XML overrides to resolve XML mapping imports.

Parameters:

  • _format (Symbol) —

    The format

  • _register (Symbol) —

    The register



70
71
72
 
# File 'lib/lutaml/model/serialize/format_conversion.rb', line 70

def pre_deserialize_hook(_format, _register)
  # No-op by default; XML overrides via prepend
end

#pre_serialize_hook(_format, _register) ⇒ Object

Hook for format-specific pre-serialization logic. XML overrides to resolve XML mapping imports.

Parameters:

  • _format (Symbol) —

    The format

  • _register (Symbol) —

    The register



253
254
255
 
# File 'lib/lutaml/model/serialize/format_conversion.rb', line 253

def pre_serialize_hook(_format, _register)
  # No-op by default; XML overrides via prepend
end

#prepare_to_options(_format, _instance, options) ⇒ Hash

Hook for format-specific options preparation before serialization. XML overrides to handle prefix, namespace overrides, declaration plan.

Parameters:

  • _format (Symbol) —

    The format

  • _instance (Object) —

    The model instance

  • options (Hash) —

    The options hash

Returns:

  • (Hash) —

    The modified options hash



215
216
217
 
# File 'lib/lutaml/model/serialize/format_conversion.rb', line 215

def prepare_to_options(_format, _instance, options)
  options
end

#process_mapping(format, *_args) ⇒ Object

Process mapping DSL for a format

Parameters:

  • format (Symbol) —

    The format (:xml, :json, etc.)

  • args (Array) —

    Additional arguments (e.g., mapping class for XML)

  • block (Proc) —

    The DSL block to evaluate



16
17
18
19
20
21
22
23
24
25
26
 
# File 'lib/lutaml/model/serialize/format_conversion.rb', line 16

def process_mapping(format, *_args, &)
  klass = ::Lutaml::Model::Config.mappings_class_for(format)
  mappings[format] ||= klass.new
  mappings[format].instance_eval(&)

  if mappings[format].respond_to?(:finalize)
    mappings[format].finalize(self)
  end

  post_process_mapping(format)
end

#reset_format_error_types_cache! ⇒ Object

Reset cached error types (for test isolation)



122
123
124
 
# File 'lib/lutaml/model/serialize/format_conversion.rb', line 122

def reset_format_error_types_cache!
  @format_error_types_base = nil
end

#to(format, instance, options = {}) ⇒ String

Serialize a model instance to a format

Parameters:

  • format (Symbol) —

    The format to serialize to

  • instance (Object) —

    The model instance

  • options (Hash) (defaults to: {}) —

    Additional options

Options Hash (options):

  • :prefix (Symbol, String, Boolean) —

    XML namespace prefix control

    • nil (default): Preserve input format during round-trip

    • true: Force prefix format using namespace’s prefix_default

    • :default: Force default namespace format (no prefix on element)

    • String: Use custom prefix string (e.g., ‘custom’)

    For round-trip fidelity, the original namespace URI (alias or canonical) is always preserved when available, regardless of this option.

Returns:

  • (String) —

    The serialized output



189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
 
# File 'lib/lutaml/model/serialize/format_conversion.rb', line 189

def to(format, instance, options = {})
  Instrumentation.instrument(:to, model: name, format: format) do
    adapter_override = options.is_a?(Hash) && options.delete(:adapter)
    if adapter_override && options.is_a?(Hash)
      options[:_adapter_override] =
        true
    end
    value = public_send(:"as_#{format}", instance, options)
    adapter = resolve_adapter(format, adapter_override)

    # Hook for format-specific options preparation (e.g., XML prefix/namespace/declaration)
    options = prepare_to_options(format, instance, options)

    adapter.new(value, register: options[:register]).public_send(
      :"to_#{format}", options
    )
  end
end

#validate_document(_format, _doc, _options, _register) ⇒ Object

Hook for format-specific document validation. XML overrides to validate root mapping and extract encoding/doctype.

Parameters:

  • _format (Symbol) —

    The format

  • _doc (Object) —

    The parsed document

  • _options (Hash) —

    Options hash (may be modified)

  • _register (Symbol) —

    The register



155
156
157
 
# File 'lib/lutaml/model/serialize/format_conversion.rb', line 155

def validate_document(_format, _doc, _options, _register)
  # No-op by default; XML overrides via prepend
end