print('ss: ' + ss + ' request.data: ' + str(request.data))
return ss

@app.route('/test/')
def t():
    return """
<html><head></head><body>
<script src="http://code.jquery.com/jquery.min.js" type="text/javascript"></script>
<script type='text/javascript'>
jQuery.ajax(
   {
      type: "POST",
      dataType: "json",
      data: "adasdasd",
    url: 'http://127.0.0.1:5000/',
complete: function(xhr, statusText)
      {  alert(xhr.responseText) }})
var oReq = new XMLHttpRequest();
oReq.open("POST", "/", false);
oReq.setRequestHeader("Content-Type", "unknown");
oReq.send('sync call');
alert(oReq.responseXML);
</script></body></html>
"""
if __name__ == '__main__':
    app.run()
Flask не получает никаких данных из данных запроса jQuery