module HappyMapper
Constants
- VERSION
Public Class Methods
# File lib/happymapper.rb, line 17 def self.included(base) if base.superclass <= HappyMapper base.instance_eval do @attributes = superclass.instance_variable_get(:@attributes).dup @elements = superclass.instance_variable_get(:@elements).dup @registered_namespaces = superclass.instance_variable_get(:@registered_namespaces).dup @wrapper_anonymous_classes = superclass.instance_variable_get(:@wrapper_anonymous_classes).dup end else base.instance_eval do @attributes = {} @elements = {} @registered_namespaces = {} @wrapper_anonymous_classes = {} end end base.extend ClassMethods end
Set all attributes with a default to their default values
# File lib/happymapper.rb, line 487 def initialize super self.class.attributes.reject { |attr| attr.default.nil? }.each do |attr| send("#{attr.method_name}=", attr.default) end end
# File lib/happymapper.rb, line 13 def self.parse(xml_content) AnonymousMapper.new.parse(xml_content) end
Public Instance Methods
Parse the xml and update this instance. This does not update instances of HappyMappers that are children of this object. New instances will be created for any HappyMapper
children of this object.
Params and return are the same as the class parse() method above.
# File lib/happymapper.rb, line 591 def parse(xml, options = {}) self.class.parse(xml, options.merge!(update: self)) end
Create an xml representation of the specified class based on defined HappyMapper
elements and attributes. The method is defined in a way that it can be called recursively by classes that are also HappyMapper
classes, allowg for the composition of classes.
@param [Nokogiri::XML::Builder] builder an instance of the XML builder which
is being used when called recursively.
@param [String] default_namespace The name of the namespace which is the
default for the xml being produced; this is the namespace of the parent
@param [String] namespace_override The namespace specified with the element
declaration in the parent. Overrides the namespace declaration in the element class itself when calling #to_xml recursively.
@param [String] tag_from_parent The xml tag to use on the element when being
called recursively. This lets the parent doc define its own structure. Otherwise the element uses the tag it has defined for itself. Should only apply when calling a child HappyMapper element.
@return [String,Nokogiri::XML::Builder] return XML representation of the
HappyMapper object; when called recursively this is going to return and Nokogiri::XML::Builder object.
# File lib/happymapper.rb, line 517 def to_xml(builder = nil, default_namespace = nil, namespace_override = nil, tag_from_parent = nil) # # If to_xml has been called without a passed in builder instance that # means we are going to return xml output. When it has been called with # a builder instance that means we most likely being called recursively # and will return the end product as a builder instance. # unless builder write_out_to_xml = true builder = Nokogiri::XML::Builder.new end attributes = collect_writable_attributes # # If the object we are serializing has a namespace declaration we will want # to use that namespace or we will use the default namespace. # When neither are specifed we are simply using whatever is default to the # builder # namespace_name = namespace_override || self.class.namespace || default_namespace # # Create a tag in the builder that matches the class's tag name unless a tag was passed # in a recursive call from the parent doc. Then append # any attributes to the element that were defined above. # builder.send("#{tag_from_parent || self.class.tag_name}_", attributes) do |xml| register_namespaces_with_builder(builder) xml.parent.namespace = builder.doc.root.namespace_definitions.find { |x| x.prefix == namespace_name } # # When a content has been defined we add the resulting value # the output xml # if (content = self.class.defined_content) unless content.options[:read_only] value = send(content.name) value = apply_on_save_action(content, value) builder.text(value) end end # # for every define element (i.e. has_one, has_many, element) we are # going to persist each one # self.class.elements.each do |element| element_to_xml(element, xml, default_namespace) end end # Write out to XML, this value was set above, based on whether or not an XML # builder object was passed to it as a parameter. When there was no parameter # we assume we are at the root level of the #to_xml call and want the actual # xml generated from the object. If an XML builder instance was specified # then we assume that has been called recursively to generate a larger # XML document. write_out_to_xml ? builder.to_xml.force_encoding('UTF-8') : builder end
Private Instance Methods
If the item defines an on_save lambda/proc or value that maps to a method that the class has defined, then call it with the value as a parameter. This allows for operations to be performed to convert the value to a specific value to be saved to the xml.
# File lib/happymapper.rb, line 614 def apply_on_save_action(item, value) if (on_save_action = item.options[:on_save]) if on_save_action.is_a?(Proc) value = on_save_action.call(value) elsif respond_to?(on_save_action) value = send(on_save_action, value) end end value end
Find the attributes for the class and collect them into a Hash structure
# File lib/happymapper.rb, line 628 def collect_writable_attributes # # Find the attributes for the class and collect them into an array # that will be placed into a Hash structure # attributes = self.class.attributes.collect do |attribute| # # If an attribute is marked as read_only then we want to ignore the attribute # when it comes to saving the xml document; so we will not go into any of # the below process # if attribute.options[:read_only] [] else value = send(attribute.method_name) value = nil if value == attribute.default # # Apply any on_save lambda/proc or value defined on the attribute. # value = apply_on_save_action(attribute, value) # # Attributes that have a nil value should be ignored unless they explicitly # state that they should be expressed in the output. # if !(value.nil? || attribute.options[:state_when_nil]) attribute_namespace = attribute.options[:namespace] ["#{attribute_namespace ? "#{attribute_namespace}:" : ''}#{attribute.tag}", value] else [] end end end.flatten Hash[*attributes] end
Persist a single nested element as xml
# File lib/happymapper.rb, line 686 def element_to_xml(element, xml, default_namespace) # # If an element is marked as read only do not consider at all when # saving to XML. # return if element.options[:read_only] tag = element.tag || element.name # # The value to store is the result of the method call to the element, # by default this is simply utilizing the attr_accessor defined. However, # this allows for this method to be overridden # value = send(element.name) # # Apply any on_save action defined on the element. # value = apply_on_save_action(element, value) # # To allow for us to treat both groups of items and singular items # equally we wrap the value and treat it as an array. # values = if value.respond_to?(:to_ary) && !element.options[:single] value.to_ary else [value] end values.each do |item| if item.is_a?(HappyMapper) # # Other items are convertable to xml through the xml builder # process should have their contents retrieved and attached # to the builder structure # item.to_xml(xml, self.class.namespace || default_namespace, element.options[:namespace], element.options[:tag] || nil) elsif !item.nil? item_namespace = element.options[:namespace] || self.class.namespace || default_namespace # # When a value exists we should append the value for the tag # if item_namespace xml[item_namespace].send("#{tag}_", item.to_s) else xml.send("#{tag}_", item.to_s) end elsif element.options[:state_when_nil] # # Normally a nil value would be ignored, however if specified then # an empty element will be written to the xml # xml.send("#{tag}_", '') end end end
Add all the registered namespaces to the builder's root element. When this is called recursively by composed classes the namespaces are still added to the root element
However, we do not want to add the namespace if the namespace is 'xmlns' which means that it is the default namespace of the code.
# File lib/happymapper.rb, line 676 def register_namespaces_with_builder(builder) return unless self.class.instance_variable_get('@registered_namespaces') self.class.instance_variable_get('@registered_namespaces').sort.each do |name, href| name = nil if name == 'xmlns' builder.doc.root.add_namespace(name, href) end end