Node.js TypeError:locations.join不是google距离矩阵中的函数

我正在使用

google distance matrix

npm包在服务器端使用google distance matrix api

我的代码如下

var distance = require('google-distance-matrix');

      getDistance: function (origin, destination) {

        distance.key('XXXXXXXXXXXXXXXXXXXXXX');
        distance.matrix(origin, destination, function (err, distance) {

          if (!err) {
            console.log(distance);
          }
        });
}

这给了我如下的错误

error: Sending 500 ("Server Error") response: 
 TypeError: locations.join is not a function

非常感谢您的帮助

var distance = require('google-distance-matrix');

      getDistance: function (origin, destination) {

        distance.key('XXXXXXXXXXXXXXXXXXXXXX');
        distance.matrix([origin], [destination], function (err, distance) {

          if (!err) {
            console.log(distance);
          }
        });
}