apache spark - check if file exists

hadoop apache-spark hdfs
Chandra picture Chandra · May 22, 2015 · Viewed 50.7k times · Source

I am new to spark and I have a question. I have a two step process in which the first step write a SUCCESS.txt file to a location on HDFS. My second step which is a spark job has to verify if that SUCCESS.txt file exists before it starts processing the data.

I checked the spark API and didnt find any method which checks if a file exists. Any ideas how to handle this?

The only method I found was sc.textFile(hdfs:///SUCCESS.txt).count() which would throw an exception when the file does not exist. I have to catch that exception and write my program accordingly. I didnt really like this approach. Hoping to find a better alternative.

Answer

DPM picture DPM · May 23, 2015

For a file in HDFS, you can use the hadoop way of doing this:

val conf = sc.hadoopConfiguration
val fs = org.apache.hadoop.fs.FileSystem.get(conf)
val exists = fs.exists(new org.apache.hadoop.fs.Path("/path/on/hdfs/to/SUCCESS.txt"))

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