class ActiveFedora::MetadataDatastream

whenever you edit the field's values.
you will end up replicating the values in the underlying datastream, resulting in mysterious dubling, quadrupling, etc.
!! Careful: If you declare two fields that correspond to the same xml node without any qualifiers to differentiate them,

There is quite a good example of this class in use in spec/examples/oral_history.rb

At some point, these modifiers will be ported up to work for any +ActiveFedora::MetadataDatastream+.

:multiple=>true - mark this field as a multivalue field (on by default)
:encoding=>foo, or encodings_scheme - causes an xsi:type attribute to be set to 'foo'
:xml_node => :nodename - The xml node to be used to represent this object (in dcterms namespace)
:element_attrs =>{:foo=>:bar} - hash of xml element attributes
For +QualifiedDublinCorDatastreams+:
Currently supported modifiers:

opts is an options hash, which will affect the generation of the xml representation of this datastream.

'tupe' is a datatype, currently :string, :text and :date are supported.

Calling any of the generated methods marks self as dirty.


name_append(arg)
name_values
name_values=(arg)
each field will have the 3 magic methods:
This method generates the various accessor and mutator methods on self for the datastream metadata attributes.

def field(name, tupe, opts={})
  @fields[name.to_s.to_sym]={:type=>tupe, :values=>[]}.merge(opts)
  eval <<-EOS
    def #{name}_values=(arg)
      @fields["#{name.to_s}".to_sym][:values]=[arg].flatten
      self.dirty=true
    end
    def #{name}_values
      @fields["#{name}".to_sym][:values]
    end
    def #{name}_append(arg)
      @fields["#{name}".to_sym][:values] << arg
      self.dirty =true
    end
  EOS
end