Class: SvgConform::Requirements::BaseRequirement

Inherits:
Lutaml::Model::Serializable
  • Object
show all
Includes:
Interfaces::RequirementInterface, NodeHelpers
Defined in:
lib/svg_conform/requirements/base_requirement.rb

Overview

Base class for all validation requirements

Validation modes

Requirements support two validation modes:

DOM validation (remediation mode)

Used when the full document is available and remediation is needed. Requirements implement validate_document to traverse the document once.

requirement.validate_document(document, context)

SAX validation (streaming mode)

Used for memory-efficient streaming validation without loading the full document. Requirements implement either immediate or deferred validation patterns.

Immediate validation (14 requirements)

Validates as it encounters each node during SAX parsing. No state is needed - validation is complete after validate_sax_element returns.

def validate_sax_element(element, context)
# Immediate validation logic
context.add_error(...) if invalid
end

Requirements using immediate validation:

  • AllowedElementsRequirement
  • FontFamilyRequirement
  • ColorRestrictionsRequirement
  • ViewboxRequiredRequirement
  • NamespaceRequirement
  • IdCollectionRequirement
  • StylePromotionRequirement
  • NoExternalImagesRequirement
  • NoExternalFontsRequirement
  • NamespaceAttributesRequirement
  • ForbiddenContentRequirement
  • StyleRequirement
  • LinkValidationRequirement (registers to ReferenceManifest)

Deferred validation (3 requirements)

Collects data during SAX parsing and validates at document end. Requires a nested State class to store collected data.

class State
attr_accessor :collected_data

def initialize
  @collected_data = []
end
end

def needs_deferred_validation?
true
end

def collect_sax_data(element, context)
state = context.state_for(self)
state.collected_data << extract_data(element)
end

def validate_sax_complete(context)
state = context.state_for(self)
# Validate collected data
end

Requirements using deferred validation:

  • IdReferenceRequirement (needs forward references to IDs)
  • InvalidIdReferencesRequirement (needs to collect IDs first)
  • NoExternalCssRequirement (needs to check style elements)

State management

Requirements needing deferred validation must define a nested State class. The ValidationContext manages state instances per requirement via state_for:

state = context.state_for(self)  # Returns State instance for this requirement

Each validation gets a fresh state instance, preventing state pollution when reusing the same profile for multiple validations.

Instance Method Summary collapse

Methods included from Interfaces::RequirementInterface

#reset_state

Methods included from NodeHelpers

#element?, #get_attribute, #has_attribute?, #remove_attribute, #set_attribute, #text?

Instance Method Details

#check(node, context) ⇒ Object

Main validation method - must be implemented by subclasses

Raises:

  • (NotImplementedError) 


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# File 'lib/svg_conform/requirements/base_requirement.rb', line 109

def check(node, context)
  raise NotImplementedError, "Subclasses must implement #check"
end

#collect_sax_data(element, context) ⇒ Object

Called for each element to collect data for deferred validation Override in subclasses that need to collect data



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# File 'lib/svg_conform/requirements/base_requirement.rb', line 131

def collect_sax_data(element, context)
  # Default: no data collection
end

#get_attributes(node) ⇒ Object

Helper method to get all attributes Note: Other attribute helpers are included via NodeHelpers module



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# File 'lib/svg_conform/requirements/base_requirement.rb', line 159

def get_attributes(node)
  return {} unless node.respond_to?(:attributes)

  attrs = node.attributes || []
  # Convert array of Moxml::Attribute objects to hash
  attrs.to_h do |attr|
    [attr.name, attr.value]
  end
end

#needs_deferred_validation? ⇒ Boolean

Indicates if requirement needs deferred validation Override to return true for requirements that need forward references

Returns:

  • (Boolean) 


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# File 'lib/svg_conform/requirements/base_requirement.rb', line 143

def needs_deferred_validation?
  false
end

#should_check_node?(node, context = nil) ⇒ Boolean

Determine if this requirement should check a specific node

Returns:

  • (Boolean) 


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# File 'lib/svg_conform/requirements/base_requirement.rb', line 148

def should_check_node?(node, context = nil)
  return false unless node.respond_to?(:name) && node.respond_to?(:attributes)

  # Skip structurally invalid nodes (and their children are automatically skipped by marking the parent)
  return false if context&.node_structurally_invalid?(node)

  true
end

#skip_attribute_validation?(node_or_element, context) ⇒ Boolean

Shared helper for skipping attribute validation on structurally invalid nodes Used by both DOM and SAX validation

Returns:

  • (Boolean) 


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# File 'lib/svg_conform/requirements/base_requirement.rb', line 171

def skip_attribute_validation?(node_or_element, context)
  # For DOM mode, also check if it's an element
  return true if element?(node_or_element) && context.node_structurally_invalid?(node_or_element)

  # For SAX mode (ElementProxy always has this method)
  if node_or_element.respond_to?(:path_id)
    return context.node_structurally_invalid?(node_or_element)
  end

  false
end

#to_s ⇒ Object 



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# File 'lib/svg_conform/requirements/base_requirement.rb', line 183

def to_s
  "#{@id}: #{@description}"
end

#validate_document(document, context) ⇒ Object

Validate the entire document (called once per requirement)



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# File 'lib/svg_conform/requirements/base_requirement.rb', line 114

def validate_document(document, context)
  document.traverse do |node|
    check(node, context) if should_check_node?(node, context)
  end
end

#validate_sax_complete(context) ⇒ Object

Called at end of document for deferred validation Override in subclasses that need full document data



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# File 'lib/svg_conform/requirements/base_requirement.rb', line 137

def validate_sax_complete(context)
  # Default: no deferred validation
end

#validate_sax_element(element, context) ⇒ Object

Called for each element during SAX parsing Override in subclasses for immediate validation



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# File 'lib/svg_conform/requirements/base_requirement.rb', line 124

def validate_sax_element(element, context)
  # Default: Empty - subclasses must override for SAX support
  # Cannot call check() here as it's abstract
end