code: function ImageUploader (inputConfig) {
      var config = Object.assign({}, defaultConfig, inputConfig)
      AWS.config.update({
        accessKeyId: config.accessKeyId,
        secretAccessKey: config.secretAccessKey,
        region: config.region
      })
      this._err = {}
      this._accessKeyId = config.accessKeyId
      this._secretAccessKey = config.secretAccessKey
      this._region = config.region
      this._bucketName = config.bucketName
      this._bucketUrl = config.bucketUrl
      this._file = config.file
      this._uploadProgress = config.uploadProgress
      this._sizeLimit = config.sizeLimit
      this._bucket = new AWS.S3({ params: { Bucket: this._bucketName } })
      return this
    }
docs: ImageUploader class