跳过数据流javascript udf中的记录

对于要跳过的记录,可以从UDF中发出未定义的记录,这些记录将不再包含在输出中。

您可以在此处查看此功能的示例: https://github.com/GoogleCloudPlatform/DataflowTemplates#filtering-records

/**
 * A transform function which only accepts 42 as the answer to life.
 * @param {string} inJson
 * @return {string} outJson
 */
function transform(inJson) {
  var obj = JSON.parse(inJson);
  // only output objects which have an answer to life of 42.
  if (obj.hasOwnProperty('answerToLife') && obj.answerToLife === 42) {
    return JSON.stringify(obj);
  }
}