Understanding JSON structure - attributes and values

Question

Something is bothering me. I've used JSON in a few of my apps/websites, we all love it! However something entered my head today which I've never thought about.. take a look at the following example (this is taken from http://json.org/example.html ):

{"widget": {
    "debug": "on",
    "window": {
        "title": "Sample Konfabulator Widget",
        "name": "main_window",
        "width": 500,
        "height": 500
    },
    "image": { 
        "src": "Images/Sun.png",
        "name": "sun1",
        "hOffset": 250,
        "vOffset": 250,
        "alignment": "center"
    },
    "text": {
        "data": "Click Here",
        "size": 36,
        "style": "bold",
        "name": "text1",
        "hOffset": 250,
        "vOffset": 100,
        "alignment": "center",
        "onMouseUp": "sun1.opacity = (sun1.opacity / 100) * 90;"
    }
}}  

now if this was expressed as XML: we would have the following:

<widget>
    <debug>on</debug>
    <window title="Sample Konfabulator Widget">
        <name>main_window</name>
        <width>500</width>
        <height>500</height>
    </window>
    <image src="Images/Sun.png" name="sun1">
        <hOffset>250</hOffset>
        <vOffset>250</vOffset>
        <alignment>center</alignment>
    </image>
    <text data="Click Here" size="36" style="bold">
        <name>text1</name>
        <hOffset>250</hOffset>
        <vOffset>100</vOffset>
        <alignment>center</alignment>
        <onMouseUp>
            sun1.opacity = (sun1.opacity / 100) * 90;
        </onMouseUp>
    </text>
</widget>

When looking at JSON to XML transformation I'm wondering if is there is any way that you can distinguish if a pair ("key":"value") are a attribute of a tag. For example, in our JSON above

"window": {
            "title": "Sample Konfabulator Widget",
            "name": "main_window",

title is represented as an attribute of the window tag whilst name is a tag in it's own right, however this isn't expressed anywhere (that I can see).

<window title="Sample Konfabulator Widget">
    <name>main_window</name>

Why isn't this displayed as:

<window>
    <title>Sample Konfabulator Widget</title>
    <name>main_window</name>

Is their a way I can specify if a pair are an attribute of the parent tag or a child tag in their own right? Sorry if my wording is bad or if I'm not explaining myself well.

Answer 1

Some people tend to use a regular property named "@attributes", giving it the special meaning of "attributes container", but that name does not have any special meaning for the JSON specifications themselves.

To answer to your question, there is no way to distinguish between pairs "key":"value" and attributes, simply because json does not support attributes.

This kind of question usually comes from people who forget that the M in XML stands for "markup", which is a way of taking plain text and adding markup to create structured text. I guess that the misunderstanding cames from promoting JSON as a fat-free alternative to XML, while actually XML is a markup language, and JSON is a data interchange format. No one is really an alternative to the other.

The mixed content is one of the contexts where XML shows its power.

<p>What a <b>mess</b> we're in.</p>

Trying to express that as JSON, you'll realize that it wasn't designed for the that job.

On the other hand, XML may be quite useful as data interchanger, but that's not what it was designed for or where it's main strengths are.