Module: HappyMapper

Extended by:
AnonymousMapper
Defined in:
lib/happymapper.rb,
lib/happymapper/item.rb,
lib/happymapper/element.rb,
lib/happymapper/version.rb,
lib/happymapper/attribute.rb,
lib/happymapper/text_node.rb,
lib/happymapper/supported_types.rb,
lib/happymapper/anonymous_mapper.rb

Defined Under Namespace

Modules: AnonymousMapper, ClassMethods, SupportedTypes Classes: AnonymousWrapperClassFactory, Attribute, Boolean, Element, Item, TextNode, XmlContent

Constant Summary collapse

DEFAULT_NS = 
"happymapper"
VERSION = 
"0.5.10"

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.included(base) ⇒ Object 



14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
 
# File 'lib/happymapper.rb', line 14

def self.included(base)
  if !(base.superclass <= HappyMapper)
    base.instance_eval do
      @attributes = {}
      @elements = {}
      @registered_namespaces = {}
      @wrapper_anonymous_classes = {}
    end
  else
    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
  end

  base.extend ClassMethods
end

Instance Method Details

#initialize ⇒ Object

Set all attributes with a default to their default values



488
489
490
491
492
493
 
# File 'lib/happymapper.rb', line 488

def initialize
  super
  self.class.attributes.reject {|attr| attr.default.nil?}.each do |attr|
    send("#{attr.method_name}=", attr.default)
  end
end

#parse(xml, options = {}) ⇒ Object

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.



744
745
746
 
# File 'lib/happymapper.rb', line 744

def parse(xml, options = {})
  self.class.parse(xml, options.merge!(:update => self))
end

#to_xml(builder = nil, default_namespace = nil, tag_from_parent = nil) ⇒ String, Nokogiri::XML::Builder

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.

Parameters:

  • builder (Nokogiri::XML::Builder) (defaults to: nil) —

    an instance of the XML builder which is being used when called recursively.

  • default_namespace (String) (defaults to: nil) —

    the name of the namespace which is the default for the xml being produced; this is specified by the element declaration when calling #to_xml recursively.

  • tag_from_parent (String) (defaults to: nil) —

    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.

Returns:

  • (String, Nokogiri::XML::Builder) —

    return XML representation of the HappyMapper object; when called recursively this is going to return and Nokogiri::XML::Builder object.



515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
 
# File 'lib/happymapper.rb', line 515

def to_xml(builder = nil,default_namespace = 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

  #
  # 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 wiill not go into any of
    # the below process
    #
    unless attribute.options[:read_only]

      value = send(attribute.method_name)
      value = nil if value == attribute.default

      #
      # If the attribute 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.
      #
      if on_save_action = attribute.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

      #
      # Attributes that have a nil value should be ignored unless they explicitly
      # state that they should be expressed in the output.
      #
      if not value.nil? || attribute.options[:state_when_nil]
        attribute_namespace = attribute.options[:namespace] || default_namespace
        [ "#{attribute_namespace ? "#{attribute_namespace}:" : ""}#{attribute.tag}", value ]
      else
        []
      end

    else
      []
    end

  end.flatten

  attributes = Hash[ *attributes ]

  #
  # 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|

    #
    # Add all the registered namespaces to the root element.
    # When this is called recurisvely 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 namesapce of the code.
    #
    if self.class.instance_variable_get('@registered_namespaces') && builder.doc.root
      self.class.instance_variable_get('@registered_namespaces').each_pair do |name,href|
        name = nil if name == "xmlns"
        builder.doc.root.add_namespace(name,href)
      end
    end

    #
    # If the object we are persisting 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
    #
    if self.class.respond_to?(:namespace) && self.class.namespace
      xml.parent.namespace = builder.doc.root.namespace_definitions.find { |x| x.prefix == self.class.namespace }
    elsif default_namespace
      xml.parent.namespace = builder.doc.root.namespace_definitions.find { |x| x.prefix == default_namespace }
    end


    #
    # When a content has been defined we add the resulting value
    # the output xml
    #
    if content = self.class.instance_variable_get('@content')

      unless content.options[:read_only]
        text_accessor = content.tag || content.name
        value = send(text_accessor)

        if on_save_action = content.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

        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|

      #
      # If an element is marked as read only do not consider at all when
      # saving to XML.
      #
      unless 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)

        #
        # If the element defines an on_save lambda/proc then we will call that
        # operation on the specified value. This allows for operations to be
        # performed to convert the value to a specific value to be saved to the xml.
        #
        if on_save_action = element.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

        #
        # Normally a nil value would be ignored, however if specified then
        # an empty element will be written to the xml
        #
        if value.nil? && element.options[:single] && element.options[:state_when_nil]
          xml.send("#{tag}_","")
        end

        #
        # To allow for us to treat both groups of items and singular items
        # equally we wrap the value and treat it as an array.
        #
        if value.nil?
          values = []
        elsif value.respond_to?(:to_ary) && !element.options[:single]
          values = value.to_ary
        else
          values = [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,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

          else

            #
            # Normally a nil value would be ignored, however if specified then
            # an empty element will be written to the xml
            #
            xml.send("#{tag}_","") if element.options[:state_when_nil]

          end

        end

      end
    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 : builder

end