aws-sdk 上传图片成功后没有给返回值，而且我要怎么获取到上传成功后图片的 url 呢

let file = item.file console.log(file.name) let accessKeyId = this.appData.accessKeyId let accessKeySecret = this.appData.accessKeySecret let bucket = this.appData.bucket let region = this.appData.region; let securityToken = this.appData.securityToken; let type = this.appData.type;

  let s3 = new AWS.S3({
    'apiVersion' : '2006-03-01',
    'accessKeyId' : accessKeyId,
    'secretAccessKey' : accessKeySecret,
    'sessionToken' : securityToken,
    'region': region,
  });
  let params = {
    Bucket: bucket, /* required */
    Key: file.name, /* required */
    Body: file
  };
  s3.putObject(params, (err, data) =>{
    if (err) {
      console.log('失败');
      console.log(err, err.stack) // an error occurred
    } else {
      // successful response
      console.log('成功');
      console.log(data)

    }

  });