How would I express XML tag attributes in JSON?

Question

I am designing an API for my webapp.

I was thinking to support only JSON responses (not XML) because more streamlined.

But I have just bumped to this XML:

Answer 1

edit

A similar method is advocated on http://www.jsonml.org/. They coined the term json markup language.

---

You can pick any mapping you like, but if you map

  txt

to

{"el":{"attr":"value","content":"txt"}}

then how would you map:

txt2

I'd make use of the fact that some attibute names are forbidden.

{"el":{"attr":"value", "content":"txt1", "":["txt"]}

Or a more compex example:

  on
  
    I just put some text here
    main_window
    500
    500
  
  
    250mm
    250
    center
  

could map to:

{"widget":{"":[
  {"debug":{"":["on"]}},
  {"window":{"title":"Sample Konfabulator Widget", "": [
    "I just put some text here",
    {"name":{"":["main window"]}},
    {"width":{"":["500"]}},
    {"height":{"":["500"]}}
  ]},
  {"image":{"src":"Images/Sun.png", "name":"sun1", "":[
    {"hOffset":{"":["250",{"unit":{"":["mm"]}}]}},
    {"vOffset":{"":["250"]}},
    {"alignment":{"":["center"]}}
  }
]}

The rules for this conversion are unambiguous:

• an element is converted to an object.
• The object key is the element name.
• The object value is an object itself, with:
  • an attibute is mapped to an object property. (key/value)
  • the object content is mapped to a special property.
    • The special property name is an empty string. This can never collide with an xml attribyte name.
    • The special property value is an array.
    • Within the array, plain text is represented as a string.
    • Within the array, elements are represented as objects, as described above.

To safe space, there is a way to unambigously simplify mentioned mapping:

{"widget":{"":[
  {"debug":"on"},
  {"window":{"title":"Sample Konfabulator Widget", "": [
    "I just put some text here",
    {"name":"main window"},
    {"width":"500"},
    {"height":"500"}
  ]},
  {"image":{"src":"Images/Sun.png", "name":"sun1", "":[
    {"hOffset":["250",{"unit":"mm"}]},
    {"vOffset":"250"},
    {"alignment":"center"}
  }
]}

• If an element doesn't have any attibutes, the value object (containing the special empty string mapping to an array) is replaced by the array directly. So instead of:

  {"hOffset":{"":["250",{"unit":{"":["mm"]}}]}}

you get

{"hOffset":["250",{"unit":["mm"]}]}

• If the element content is just text, the array containing the string value is replaced by the string value directly, so you get:

  {"hOffset":["250",{"unit":"mm"}]}

This way, there will always be exactly one way to map the jml (json markup language) back to xml (or html)