Class: Lutaml::Lml::Executor::XmlAdapter

Inherits:
Object
  • Object
show all
Extended by:
AdapterHelpers
Defined in:
lib/lutaml/lml/executor/xml_adapter.rb

Overview

XML format adapter. Reads XML files and maps elements to hydrated compiled-class instances, and writes instances back to XML.

Registered for format "xml" via FormatAdapter::BUILTIN_ADAPTERS.

Element-to-attribute mapping is provided by the lutaml-model XML mapping generated on each compiled class by ModelCompiler. This adapter only selects which XML elements correspond to records (via the where XPath from the import definition) and hands each one to target_class.from_xml for deserialization.

Import shape (from LML import { xml "..." { map_to X; where "/y" } }):

- imp.file             = path to XML file
- imp.attributes       = TopElementAttribute list including:
  map_to: TargetClass (compiled-class key)
  where:  XPath selector for each record element

Export shape (from LML export { format xml { file "..."; root "X" } }):

- exp.attributes       = TopElementAttribute list including:
  file:      output path
  root:      root tag name (defaults to compiled class name)
  indent:    "true" / "false" (default true)
  encoding:  encoding string (default UTF-8)

Constant Summary collapse

DEFAULT_ENCODING = 
"UTF-8"
DEFAULT_SELECTOR = 
"/*/*"
DEFAULT_ROOT_SUFFIX = 
"s"

Class Method Summary collapse

Methods included from AdapterHelpers

attribute_value, find_attribute, find_class_for_instance, resolve_target_class

Class Method Details

.export(exp, instances, compiled:) ⇒ Object

Write instances to an XML file.



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# File 'lib/lutaml/lml/executor/xml_adapter.rb', line 60

def export(exp, instances, compiled:)
  return if instances.empty?

  path = attribute_value(exp.attributes, "file")
  return unless path && !path.empty?

  class_name, target_class = find_class_for_instance(instances.first, compiled)
  return unless target_class

  options = export_options(exp, class_name)
  File.write(path, build_export_xml(instances, options))
end

.import(imp, compiled:) ⇒ Object

Read an XML file and map elements to compiled-class instances. Returns an array of hydrated objects.



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# File 'lib/lutaml/lml/executor/xml_adapter.rb', line 41

def import(imp, compiled:)
  return [] unless imp.file
  return [] unless imp.attributes&.any?

  target_class = resolve_target_class(imp.attributes, compiled)
  return [] unless target_class

  path = imp.file
  return [] unless File.exist?(path)

  doc = Moxml.parse(File.read(path))
  selector = attribute_value(imp.attributes, "where") || DEFAULT_SELECTOR

  doc.xpath(selector).map do |element|
    target_class.from_xml(element.to_xml)
  end
end