cos.getObject({
    Bucket: 'examplebucket-1250000000', /* Your bucket name. Required. */
    Region: 'COS_REGION',  /* Bucket region, such as `ap-beijing`. Required. */
    Key: '1.jpg',  /* Object key stored in the bucket (such as `1.jpg` and `a/b/test.txt`). Required. */
}, function(err, data) {
    console.log(err || data.Body);
});

cos.getObject({
    Bucket: 'examplebucket-1250000000', /* Your bucket name. Required. */
    Region: 'COS_REGION',  /* Bucket region, such as `ap-beijing`. Required. */
    Key: '1.jpg',  /* Object key stored in the bucket (such as `1.jpg` and `a/b/test.txt`). Required. */
    Range: 'bytes=1-3', /*Optional*/
}, function(err, data) {
    console.log(err || data.Body);
});

cos.getObject({
    Bucket: 'examplebucket-1250000000', /* Required */
    Region: 'COS_REGION',     /* Bucket region. Required */
    Key: 'exampleobject', /* Required */
    Headers: {
      'x-cos-traffic-limit': 819200, // The speed range is 819200 to 838860800, that is 100 KB/s to 100 MB/s. If the value is not within this range, 400 will be returned.
    },
}, function(err, data) {
    console.log(err || data.Body);
});

cos.getObjectUrl({
    Bucket: 'examplebucket-1250000000', /* Your bucket name. Required. */
    Region: 'COS_REGION',  /* Bucket region, such as `ap-beijing`. Required. */
    Key: '1.jpg',  /* Object key stored in the bucket (such as `1.jpg` and `a/b/test.txt`). Required. */
    Sign: true
}, function (err, data) {
    if (err) return console.log(err);
    wx.downloadFile({
        url: data.Url, // The “url” domain name needs to be added to the download allowlist
        success (res) {
            console.log(res.statusCode, res.tempFilePath);
        },
        fail: function (err) {
            console.log(err);
        },
    });
});

function(err, data) { ... }