方案一(使用ForeachWriter Sink方式):
val query = wordCounts.writeStream.trigger(ProcessingTime(5.seconds)) .outputMode("complete") .foreach(new ForeachWriter[Row] { var fileWriter: FileWriter = _ override def process(value: Row): Unit = { fileWriter.append(value.toSeq.mkString(",")) } override def close(errorOrNull: Throwable): Unit = { fileWriter.close() } override def open(partitionId: Long, version: Long): Boolean = { FileUtils.forceMkdir(new File(s"/tmp/example/${partitionId}")) fileWriter = new FileWriter(new File(s"/tmp/example/${partitionId}/temp")) true } }).start()
方案二(ds.writeStream().partitionBy(“field”)):
import org.apache.spark.sql.streaming.ProcessingTime val query = streamingSelectDF .writeStream .format("parquet") .option("path", "/mnt/sample/test-data") .option("checkpointLocation", "/mnt/sample/check") .partitionBy("zip", "day") .trigger(ProcessingTime("25 seconds")) .start()
java代码:
// Write new data to Parquet files // can be "orc", "json", "csv", etc. String hdfsFileFormat = SparkHelper.getInstance().getLTEBaseSaveHdfsFileFormat(); String queryName = "save" + this.getTopicEncodeName(topicName) + "DataToHdfs"; String saveHdfsPath = SparkHelper.getInstance().getLTEBaseSaveHdfsPath(); // The file path which partitioned by scan_start_time (format:yyyyMMddHH0000) dsParsed.writeStream() .format(hdfsFileFormat) .option("path", saveHdfsPath + topicName + "/") .option("checkpointLocation", this.checkPointPath + queryName + "/") .outputMode("append") .partitionBy("scan_start_time") .trigger(Trigger.ProcessingTime(5, TimeUnit.MINUTES)) .start();
更多方式,请参考《在Spark结构化流readStream、writeStream 输入输出,及过程ETL》