Unable to create RDD from data in HDFS - apache-spark

Question

I am tying to create an RDD using the code but unable to do it. Is there any solution to this issue.
I have tried to run it with the localhost:port details. I have also tried running it with the entire path of the HDFS:/user/training/intel/NYSE.csv. Any path i am using is being serached only on the local directory but not on hdfs.
Thanks
scala> val myrdd = sc.textFile("/training/intel/NYSE.csv")
myrdd: org.apache.spark.rdd.RDD[String] = /training/intel/NYSE.csv MapPartitionsRDD[5] at textFile at <console>:24
scala> myrdd.collect
org.apache.hadoop.mapred.InvalidInputException: Input path does not exist: file:/training/intel/NYSE.csv
at org.apache.hadoop.mapred.FileInputFormat.singleThreadedListStatus(FileInputFormat.java:287)
at org.apache.hadoop.mapred.FileInputFormat.listStatus(FileInputFormat.java:229)
at org.apache.hadoop.mapred.FileInputFormat.getSplits(FileInputFormat.java:315)
at org.apache.spark.rdd.HadoopRDD.getPartitions(HadoopRDD.scala:200)
at org.apache.spark.rdd.RDD$$anonfun$partitions$2.apply(RDD.scala:248)
at org.apache.spark.rdd.RDD$$anonfun$partitions$2.apply(RDD.scala:246)
at scala.Option.getOrElse(Option.scala:121)
at org.apache.spark.rdd.RDD.partitions(RDD.scala:246)
at org.apache.spark.rdd.MapPartitionsRDD.getPartitions(MapPartitionsRDD.scala:35)
at org.apache.spark.rdd.RDD$$anonfun$partitions$2.apply(RDD.scala:248)
at org.apache.spark.rdd.RDD$$anonfun$partitions$2.apply(RDD.scala:246)
at scala.Option.getOrElse(Option.scala:121)
at org.apache.spark.rdd.RDD.partitions(RDD.scala:246)
at org.apache.spark.SparkContext.runJob(SparkContext.scala:1911)
at org.apache.spark.rdd.RDD$$anonfun$collect$1.apply(RDD.scala:893)
at org.apache.spark.rdd.RDDOperationScope$.withScope(RDDOperationScope.scala:151)
at org.apache.spark.rdd.RDDOperationScope$.withScope(RDDOperationScope.scala:112)
at org.apache.spark.rdd.RDD.withScope(RDD.scala:358)
at org.apache.spark.rdd.RDD.collect(RDD.scala:892)
... 48 elided
I also tried the following:
scala> val myrdd = sc.textFile("hdfs://localhost:8020/training/intel/NYSE.csv")
myrdd: org.apache.spark.rdd.RDD[String] = hdfs://localhost:8020/training/intel/NYSE.csv MapPartitionsRDD[7] at textFile at <console>:24
scala> myrdd.collect
java.io.IOException: Failed on local exception: com.google.protobuf.InvalidProtocolBufferException: Protocol message contained an invalid tag (zero).; Host Details : local host is: "hadoop/127.0.0.1"; destination host is: "localhost":8020;
at org.apache.hadoop.net.NetUtils.wrapException(NetUtils.java:776)
at org.apache.hadoop.ipc.Client.call(Client.java:1479)
at org.apache.hadoop.ipc.Client.call(Client.java:1412)
at org.apache.hadoop.ipc.ProtobufRpcEngine$Invoker.invoke(ProtobufRpcEngine.java:229)
at com.sun.proxy.$Proxy24.getFileInfo(Unknown Source)
at org.apache.hadoop.hdfs.protocolPB.ClientNamenodeProtocolTranslatorPB.getFileInfo(ClientNamenodeProtocolTranslatorPB.java:771)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at org.apache.hadoop.io.retry.RetryInvocationHandler.invokeMethod(RetryInvocationHandler.java:191)
at org.apache.hadoop.io.retry.RetryInvocationHandler.invoke(RetryInvocationHandler.java:102)
at com.sun.proxy.$Proxy25.getFileInfo(Unknown Source)
at org.apache.hadoop.hdfs.DFSClient.getFileInfo(DFSClient.java:2108)
at org.apache.hadoop.hdfs.DistributedFileSystem$22.doCall(DistributedFileSystem.java:1305)
at org.apache.hadoop.hdfs.DistributedFileSystem$22.doCall(DistributedFileSystem.java:1301)
at org.apache.hadoop.fs.FileSystemLinkResolver.resolve(FileSystemLinkResolver.java:81)
at org.apache.hadoop.hdfs.DistributedFileSystem.getFileStatus(DistributedFileSystem.java:1317)
at org.apache.hadoop.fs.Globber.getFileStatus(Globber.java:57)
at org.apache.hadoop.fs.Globber.glob(Globber.java:252)
at org.apache.hadoop.fs.FileSystem.globStatus(FileSystem.java:1674)
at org.apache.hadoop.mapred.FileInputFormat.singleThreadedListStatus(FileInputFormat.java:259)
at org.apache.hadoop.mapred.FileInputFormat.listStatus(FileInputFormat.java:229)
at org.apache.hadoop.mapred.FileInputFormat.getSplits(FileInputFormat.java:315)
at org.apache.spark.rdd.HadoopRDD.getPartitions(HadoopRDD.scala:200)
at org.apache.spark.rdd.RDD$$anonfun$partitions$2.apply(RDD.scala:248)
at org.apache.spark.rdd.RDD$$anonfun$partitions$2.apply(RDD.scala:246)
at scala.Option.getOrElse(Option.scala:121)
at org.apache.spark.rdd.RDD.partitions(RDD.scala:246)
at org.apache.spark.rdd.MapPartitionsRDD.getPartitions(MapPartitionsRDD.scala:35)
at org.apache.spark.rdd.RDD$$anonfun$partitions$2.apply(RDD.scala:248)
at org.apache.spark.rdd.RDD$$anonfun$partitions$2.apply(RDD.scala:246)
at scala.Option.getOrElse(Option.scala:121)
at org.apache.spark.rdd.RDD.partitions(RDD.scala:246)
at org.apache.spark.SparkContext.runJob(SparkContext.scala:1911)
at org.apache.spark.rdd.RDD$$anonfun$collect$1.apply(RDD.scala:893)
at org.apache.spark.rdd.RDDOperationScope$.withScope(RDDOperationScope.scala:151)
at org.apache.spark.rdd.RDDOperationScope$.withScope(RDDOperationScope.scala:112)
at org.apache.spark.rdd.RDD.withScope(RDD.scala:358)
at org.apache.spark.rdd.RDD.collect(RDD.scala:892)
... 48 elided
Caused by: com.google.protobuf.InvalidProtocolBufferException: Protocol message contained an invalid tag (zero).
at com.google.protobuf.InvalidProtocolBufferException.invalidTag(InvalidProtocolBufferException.java:89)
at com.google.protobuf.CodedInputStream.readTag(CodedInputStream.java:108)
at org.apache.hadoop.ipc.protobuf.RpcHeaderProtos$RpcResponseHeaderProto.<init>(RpcHeaderProtos.java:2201)
at org.apache.hadoop.ipc.protobuf.RpcHeaderProtos$RpcResponseHeaderProto.<init>(RpcHeaderProtos.java:2165)
at org.apache.hadoop.ipc.protobuf.RpcHeaderProtos$RpcResponseHeaderProto$1.parsePartialFrom(RpcHeaderProtos.java:2295)
at org.apache.hadoop.ipc.protobuf.RpcHeaderProtos$RpcResponseHeaderProto$1.parsePartialFrom(RpcHeaderProtos.java:2290)
at com.google.protobuf.AbstractParser.parsePartialFrom(AbstractParser.java:200)
at com.google.protobuf.AbstractParser.parsePartialDelimitedFrom(AbstractParser.java:241)
at com.google.protobuf.AbstractParser.parseDelimitedFrom(AbstractParser.java:253)
at com.google.protobuf.AbstractParser.parseDelimitedFrom(AbstractParser.java:259)
at com.google.protobuf.AbstractParser.parseDelimitedFrom(AbstractParser.java:49)
at org.apache.hadoop.ipc.protobuf.RpcHeaderProtos$RpcResponseHeaderProto.parseDelimitedFrom(RpcHeaderProtos.java:3167)
at org.apache.hadoop.ipc.Client$Connection.receiveRpcResponse(Client.java:1086)
at org.apache.hadoop.ipc.Client$Connection.run(Client.java:979)
No matter how I run it, i am getting that the path doesn't exist.

Answer 1

The files are in HDFS.
Spark has been configured to read from your local filesystem file:/
You need to edit your core-site.xml file in your Spark installation directory to make sure that fs.defaultFS is set up correctly to use your Hadoop Namenode
InvalidProtocolBufferException: Protocol message contained an invalid tag (zero).; Host Details : local host is: "hadoop/127.0.0.1"; destination host is: "localhost":8020;
This would imply that your Spark HDFS client is not compatible with the installed Hadoop server APIs or you're connecting to the wrong port
And also, the file is not at hdfs:///training/.. anyway.
Besides that, HDFS isn't required to learn Spark, so maybe try playing with hadoop fs commands first or move files to local system, depending on what your goals are

Answer 2

This happens due to internal mapping between directories. First go to the directory where your file (NYSE.csv) is kept. run command :
df -k
You will get the actual mount point of the directory. For example: /xyz
Now, try finding your file(NYSE.csv) within this mount point. For example: /xyz/training/intel/NYSE.csv and use this path in your code.
val myrdd = sc.textfile("/xyz/training/intel/NYSE.csv");

Answer 3

"/training/intel/NYSE.csv"
means "start looking from the top level directory". Either change it to "/user/training/intel/NYSE.csv" or just "training/intel/NYSE.csv" (no leading /) to reference a file relative to your current directory.