From: "NAKAMURA, Hiroshi" <nahi@...>
Date: 2002-03-19T13:23:10+09:00
Subject: Re: [ANN] Xml Serialization for Ruby

Hi Chris,

> From: Chris Morris [mailto:chrismo@charter.net] 
> Sent: Tuesday, March 19, 2002 12:07 PM

> In your opinion, do you possibly see a need for a
> serializer like mine?

Yes.  Regarding "human readable and editable XML", there
must be a need for a new serializer.  SOAP might oriented
to do so but the current SOAP spec is too complex to
read/edit by human.  SOAP4R is following SOAP spec so
that the serializer of SOAP4R is unsuitable for this
purpose.

> Or do you think it'd mostly be 
> duplicated effort?

Hmm.  I'm sorry but I think so for now.  From my SOAP
experience, the balance between "human readable" and
"completion as a program".  For example, you said the
envelope stuff wass superfluous but the envelope and
id/hrefs are for multi-referenced object.  You may think
Header and Body is also superfluous but the Header
element can be used for extension.

require 'soap/marshal'

class Hobbit
  attr_accessor :name, :friend
end

class Hobbits < Array
  @@typeName = 'Hobbit'
end

frodo = Hobbit.new
frodo.name = 'Frodo'
peregrin = Hobbit.new
peregrin.name = 'Peregrin'
peregrin.friend = frodo
meriadoc = Hobbit.new
meriadoc.name = 'Meriadoc'
meriadoc.friend = frodo

puts SOAP::Marshal.marshal( Hobbits[ frodo, peregrin, meriadoc ] )
# Sorry, Sam.

=>

<?xml version="1.0" ?>
<env:Envelope xmlns:xsd="http://www.w3.org/2001/XMLSchema"
    xmlns:env="http://schemas.xmlsoap.org/soap/envelope/"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
  <env:Body>
    <Hobbits
        xmlns:n1="http://schemas.xmlsoap.org/soap/encoding/"
        xmlns:n2="http://www.ruby-lang.org/xmlns/ruby/type/1.6"
        xsi:type="n1:Array"
        n1:arrayType="n2:Hobbit[3]"
        env:encodingStyle="http://schemas.xmlsoap.org/soap/encoding/">
      <item href="#id84945296"></item>
      <item
          xmlns:n3="http://www.ruby-lang.org/xmlns/ruby/type/custom"
          xsi:type="n3:Hobbit">
        <name xsi:type="xsd:string">Peregrin</name>
        <friend href="#id84945296"></friend>
      </item>
      <item
          xmlns:n4="http://www.ruby-lang.org/xmlns/ruby/type/custom"
          xsi:type="n4:Hobbit">
        <name xsi:type="xsd:string">Meriadoc</name>
        <friend href="#id84945296"></friend>
      </item>
    </Hobbits>
    <item
        id="id84945296"
        xmlns:n5="http://schemas.xmlsoap.org/soap/encoding/"
        xsi:type="n6:Hobbit"
        xmlns:n6="http://www.ruby-lang.org/xmlns/ruby/type/custom"
        env:encodingStyle="http://schemas.xmlsoap.org/soap/encoding/">
      <name xsi:type="xsd:string">Frodo</name>
    </item>
  </env:Body>
</env:Envelope>

As against SOAP, XML-RPC drops multi-ref-ed object,
user defined type and so on so that XML instance of
XML-RPC may be much readable/editable for human.  Instead
of this, it is hard for XML-RPC to unmarshal multi-ref-ed
object and user defined type information.  You must
extend the spec proprietary if you want. (__class__
thing in [ruby-talk:36086] is a kind of this extension,
IIRC.  That might be a bad example.  XML instance of
XML-RPC usually more simple.  Sorry, Michael)

Regards,
// NaHi