node.js - Post request method on server calling twice. Why so? -

1st time, doing expected thing. don't know why calling again , though have undefined checks over, still printing.

router.post('/:id?', function (req, res) {     var id = req.params.id;     console.log(id);     if (id!== 'undefined') {         debugger;     console.log(req.method);       console.log('body: ' + json.stringify(req.body));         console.log(req.body.query.tostring());     }      if(req.body != 'undefined')         res.render('index', { title: 'shisodia mimanshu', query: 'random query', text: 'success 111' + req.body.query }); }); 

output @ console:

1  post body: {"query":"hahahhahahha"}  hahahhahahha  post /1 200 55.494 ms - 1015  undefined  post  body: {}  post / 500 13.445 ms - 1408 

the response post method not sent reason getting 2 outputs.the server call ends once response sent client. , checking id null should changes 'undefined', 'undefined' string.

router.post('/:id?', function (req, res) { var id = req.params.id; console.log(id); if (id!= null) {     debugger; console.log(req.method);   console.log('body: ' + json.stringify(req.body));     console.log(req.body.query.tostring()); res.end('completed') }  if(req.body != null)     res.render('index', { title: 'shisodia mimanshu', query: 'random query', text: 'success     111' + req.body.query }); res.end('done') }); 

hope helps.