Posting JSON using JQuery and to set HTTP content type - 'application /json'
Can you try this,
$.ajax({ beforeSend: function(xhrObj){ xhrObj.setRequestHeader("Content-Type","application/json"); xhrObj.setRequestHeader("Accept","application/json"); }, type: "POST", url: uri, data: jsonStrJson, dataType: "json", success: function(json){ console.log(json); }});