What is correct directory path format on Windows for StreamingContext.textFileStream? - scala

Question

I am trying to execute a spark streaming application to process the stream of files data to perform word count.
The directory I am reading is from Windows. As shown I using the local directory like "Users/Name/Desktop/Stream".It is not HDFS.
I created a folder as "Stream" in desktop.
I started the Spark Streaming application and after that I added some text files into the folder 'Stream'. But my spark application is not able to read the files. It is always giving the empty results.
Here is my code.
//args(0) = local[2]
object WordCount {
def main(args: Array[String]) {
val ssc = new StreamingContext(args(0), "word_count",Seconds(5))
val lines = ssc.textFileStream("Users/name/Desktop/Stream")
val words = lines.flatMap(_.split(" "))
val wordCounts = words.map(x => (x, 1)).reduceByKey(_ + _)
wordCounts.print()
ssc.start()
ssc.awaitTermination()
}
}
Output: Getting empty data every 5 seconds
17/05/18 07:35:00 INFO Executor: Running task 0.0 in stage 71.0 (TID 35)
-------------------------------------------
Time: 1495107300000 ms
-------------------------------------------
I tried giving the path as C:/Users/name/Desktop/Stream as well - still the same issue and application could not read the files.
Can anyone please guide if I am giving the incorrect directory path ?

Answer 1

Your code's fine so the only issue is to use proper path to the directory. Please use file:// prefix to denote local file system that would give file://C:/Users/name/Desktop/Stream.
Please start one step at a time to confirm that our understanding is at the same level.
When you execute the Spark Streaming application, create the directory to be in the same directory where you start the application, say Stream. Once you confirm that the application works fine with the local directory we'll fix it globally to read from any directory on Windows (if that's still needed).
Please also make sure that you "move" your files as the operation to create a file in the monitored directory has to be atomic (partial writes will mark the file as processed - see StreamingContext).
Files must be written to the monitored directory by "moving" them from another location within the same file system.
As you can see in the code the directory path will eventually be "wrapped" using Hadoop's File so the issue is to convince it to accept your path:
if (_path == null) _path = new Path(directory)