There are two saveAs operators in DStream:
-
saveAsObjectFiles
-
saveAsTextFiles
They are output operators that return nothing as they save each RDD in a batch to a storage.
Their full signature is as follows:
saveAsObjectFiles(prefix: String, suffix: String = ""): Unit
saveAsTextFiles(prefix: String, suffix: String = ""): Unit
Note
|
SaveAs operators use foreachRDD output operator. |
saveAsObjectFiles
uses RDD.saveAsObjectFile while saveAsTextFiles
uses RDD.saveAsTextFile.
The file name is based on mandatory prefix
and batch time
with optional suffix
. It is in the format of [prefix]-[time in milliseconds].[suffix]
.