XEP-xxxx: JSON Content Type support

4.1.1 Request

POST /http-bind HTTP/1.1
Host: httpcm.jabber.org
Accept-Encoding: gzip, deflate
Content-Type: application/jsonrequest
Content-Length: 230
    

4.1.2 Response

HTTP/1.1 200 OK
Content-Type: application/jsonrequest
Content-Length: 513

4.2.1 Client request

POST /http-bind HTTP/1.1
Host: httpcm.jabber.org
Accept-Encoding: gzip, deflate
Content-Type: application/jsonrequest
Content-Length: 230

{ "body" : {
  "hold" : 1,
  "ver" : "1.6",
  "wait" : 285,
  "requests" : 2,
  "rid" : 2669000493,
  "to" : "server.com",
  "lang" : { "$$" : "xml", "$" : "en" },
  "version" : { "$$" : "xmpp", " : "1.0" },
  "xmlns" : {
    "$", "http://jabber.org/protocol/httpbind",
    "@xmpp" : "urn:xmpp:xbosh" }
  }
}

4.2.2 Server response

HTTP/1.1 200 OK
Content-Type: application/jsonrequest
Content-Length: 513

{ "body" : {
  "sid" : "b1165122e8856a087c0be4c53c229713a95d8ce6",
  "wait" : "285",
  "requests" : "2",
  "inactivity" : "30",
  "maxpause" : "120",
  "polling" : "2",
  "ver" : "1.6",
  "from" : "server.com",
  "secure" : "true",
  "authid" : "1402940319",
  "xmlns" : {
    "$" : "http://jabber.org/protocol/httpbind",
    "@xmpp" : "urn:xmpp:xbosh",
    "@stream" : "http://etherx.jabber.org/streams"
  },
  "version" : { "$$" : "xmpp", "$" : "1.0" },
  "$" : {
    "features" : {
      "$$" : "stream",
      "$" : {
        "mechanisms" : {
          "xmlns" : "urn:ietf:params:xml:ns:xmpp-sasl",
          "$" : { "mechanism" : "PLAIN" }
        }
      }
    }
  }
}

4.2.3 JSON syntax explained

• Tag with text value
XMPP-XML:

<tag>txt-value</tag>

JSON:

{ "tag" : "txt-value" }

• Tag with another tag
XMPP-XML:

<tag>
 <tag2>txt-value</tag2>
</tag>

JSON:

{ "tag" : {
  "$" : {
    "tag2" : "txt-value" }
  }
}

• Multiple text value tags as array
XMPP-XML:

<tag>
 <tag2>txt-value1</tag2>
 <tag2>txt-value2</tag2>
</tag>

JSON:

{ "tag" : {
  "$" : {
    "tag2" : [ "txt-value1", "txt-value2" ] }
  }
}

• Tag with attribute, no value
XMPP-XML:

<tag attr="attr-value" />

JSON:

{ "tag" : { "attr" : "attr-value" } }

• Tag with multiple attributes as array, no value
XMPP-XML:

<tag attr="attr-value1" attr="attr-value2" />

JSON:

{ "tag" : {
  "attr" : [ "attr-value1", "attr-value2" ] }
}

• Tags as array with unique attributes, no value
XMPP-XML:

<tag>
 <tag2 attr="attr-value1" />
 <tag2 attr="attr-value2" />
</tag>

JSON:

{ "tag" : {
  "tag2" : [ 
    { "attr" : "attr-value1" },
    { "attr" : "attr-value2" } ]
  }
}

• Tag with namespace attribute, no value
XMPP-XML:

<tag xmlns:ns="ns-value" />

JSON:

{ "tag" : {
  "xmlns" : {
    "@ns" : "attr-value" }
  }
}

• Tag with many attributes to namespace, no value
XMPP-XML:

<tag xmlns="root-value" xmlns:ns="ns-value" />

JSON:

{ "tag" : {
  "xmlns" : {
    "$" : "root-value",
    "@ns" : "attr-value" }
  }
}

• Tag with namespace attribute, no value
XMPP-XML:

<ns:tag attr="attr-value" />

JSON:

{ "tag" : {
  "$$" : "ns",
  "attr" : "attr-value" }
}

• Tag with attribute and text value
XMPP-XML:

<tag attr="attr-value">txt-value</tag>

JSON:

{ "tag" : {
  "attr" : "attr-value",
  "$" : "txt-value" }
}

• Namespace tag with attribute and text value
XMPP-XML:

<ns:tag attr="attr-value">txt-value</tag>

JSON:

{ "tag" : {
  "$$" : "ns",
  "attr" : "attr-value",
  "$" : "txt-value" }
}

• Complex combination
• Tag name conversions

JSON data is typically converted to JS-object in browser client. Practically this means that tag string name / value string pairs are converted to tag name / value string pairs. Example:

var s = '{ "key" : "value" }';
var sObj = JSON.parse(s);        // sObj = { key : "value" };
var sStr = JSON.stringify(sObj); // sStr = '{"key":"value"}';

Javascript variable naming doesn't support full colon characters ':'. Intented conversion between JSON and JS-objects is based on native JavaScript class JSON, more spesifically methods JSON.stringify() for converting object to JSON, and JSON.parse() from JSON to object.
Because of this namespace definitions are constructed hiearchically and their scope is within tag it is defined. Currently only reserved namespace name is 'xml'.

First draft.