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) 


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# File 'lib/lutaml/model/serialize/format_conversion.rb', line 170

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



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# File 'lib/lutaml/model/serialize/format_conversion.rb', line 230

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



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# File 'lib/lutaml/model/serialize/format_conversion.rb', line 316

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



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# File 'lib/lutaml/model/serialize/format_conversion.rb', line 88

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



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# File 'lib/lutaml/model/serialize/format_conversion.rb', line 47

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



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# File 'lib/lutaml/model/serialize/format_conversion.rb', line 267

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



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# File 'lib/lutaml/model/serialize/format_conversion.rb', line 305

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



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# File 'lib/lutaml/model/serialize/format_conversion.rb', line 137

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



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# File 'lib/lutaml/model/serialize/format_conversion.rb', line 37

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



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# File 'lib/lutaml/model/serialize/format_conversion.rb', line 75

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



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# File 'lib/lutaml/model/serialize/format_conversion.rb', line 258

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



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# File 'lib/lutaml/model/serialize/format_conversion.rb', line 220

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



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# File 'lib/lutaml/model/serialize/format_conversion.rb', line 16

def process_mapping(format, *_args, &)
  klass = ::Lutaml::Model::Config.mappings_class_for(format)
  existing = mappings[format]
  mappings[format] = if existing.nil? || !existing.is_a?(klass)
                       klass.new
                     else
                       existing
                     end
  mappings[format].instance_eval(&)

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

  post_process_mapping(format)
end

#rdf(&block) ⇒ Object

Define RDF mappings for multiple formats (Turtle, JSON-LD, etc.). Discovers RDF formats dynamically from FormatRegistry.

Parameters:

  • block (Proc) —

    The DSL block



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# File 'lib/lutaml/model/serialize/format_conversion.rb', line 285

def rdf(&block)
  Lutaml::Model::FormatRegistry.rdf_formats.each do |format|
    mappings[format] = Lutaml::Rdf::Mapping.new
    mappings[format].instance_eval(&block)
  end
end

#reset_format_error_types_cache! ⇒ Object

Reset cached error types (for test isolation)



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# File 'lib/lutaml/model/serialize/format_conversion.rb', line 127

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



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# File 'lib/lutaml/model/serialize/format_conversion.rb', line 194

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



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# File 'lib/lutaml/model/serialize/format_conversion.rb', line 160

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