“Otherwise, you are losing some information in the translation and there is no more structural equivalence between the XML and JSON.”

Yes.

There are two problems though: is the child of items an array or an object? If it depends on the number of children, this is very error prone for the client.

People don’t want to write large code in JS to access data. For example compare:

mycart = ...
mycart.cart.items.item[0].name

vs.

mycart = ....
mycart.items[0].name

Many people consider the second one more readable.

one

to at least

{ cart: { “items”: { item: { “name”: “one” } } } }

Otherwise, you are losing some information in the translation and there is no more structural equivalence between the XML and JSON.

As other people pointed out, converting a one element nested tag to a singleton list is a matter of 1) conventions or 2) typing. I think in common XML based tools I use like Ant or Maven, it is a common assumption that the pattern … denotes a collection.

Regards.

PS; thanks for your excellent articles !

i think that we must separate problem:

1] XML is extensible because one document don’t have a real semantic, i want to say that a text like this means nothing:

one
two

when i say ‘this tag means that’ every things it’s ok and this is the task of DTD
and XSD

2] Namespaces born to avoid conflict and give a way to express some kind of semantic relations…

3] XML has a DOM and this is important: it’s the description of ‘HOW’ and not ‘WHAT’
Also for this XML it’s useful… Parsing…Parsing…

4] since other points, we can try with a simulation of DOM not of XML it’s self!
But one point of attention: this is a way to make a traslation… So it’s right
to say:”there’s no simple way to traslate XML to JSON”… Preserve the value
of X of XML it’s the real problem…

{
name:’cart’,
type:ROOT,
attributes:[],
value:”
childs:[
{
name:'items',
type:NODE,
attributes:[],
value:”
childs:[
{
name:'item',
type:NODE,
attributes:[],
value:”
childs:{
name:’name’,
type:NODE,
attributes:[],
value:’one’
childs:{}
}
} ,
{
name:’item’,
type:NODE,
attributes:[],
value:”
childs:{
name:’name’,
type:NODE,
attributes:[],
value:’one’
childs:{}
}
}
]
}
]
}

Now i can generate also schema or apply schema…
About me the summary is that XML is a textual specification with XSD as meta-specification and if i have some software that use it, complexity can’t be eliminated and must percolate to JSON…
All The Best

MrZ

@David: Yes, a schema is the same as “type” or a namespace like list:items – some meta information about the structure.

But when transforming XML to JSON within the browser using a schema

a.) the schema is slow, needs another request and isn’t very easy to implement
b.) is not generic, item needs to be defined. When not being generic but specific it would be easier to write a list_xml2json.xsl file

http://stephan.reposita.org/archives/2008/04/04/rest-lean-json-and-xml-from-the-same-code/

{ items: [ 1, 2, 3] } cannot be converted to XML, because the type of “1″ etc is missing.

One would need { items: { item: [1,2,3] } } to generate XML. Which is in itself no nice JSON.