code: function streamFile(namespace, fileName) {
    var file;
    if (namespace) {
      file = path.join(namespace, fileName);
    } else {
      file = fileName;
    }
    var deferred = q.defer();
    var paramsStream = {
      Bucket: config.bucket,
      Key: file
    };
    try {
      var stream = awsClient.downloadStream(paramsStream);
      deferred.resolve(stream);
    } catch (error) {
      console.log(error);
      deferred.reject(error);
    }
    return deferred.promise;
  }
docs: Retrieve file stream from storage
  
  @param {string} namespace - location (folder) used to place saved file.
  @param {string} fileName - filename that should be unique within namespace