apiquery.js

app.post('/api/query', function (req, res) {
  if (req.body.query) {
      async.waterfall([
        function (next) {
          var query=req.body.query;
          
          console.log(query);
          connection.query(query, next);
        },
        function (rows, fields, next) {
          next(null,rows);
        }
      ], function (error, result) {
        if (error) {
          res.send(403, error.toString());
        } else {
          res.json(result);
        }
      });
    } else {
      res.send(500, "Internal Server Error");
    }
});