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Re: use S3 as input to MR job
I'm having a similar issue

I'm running a wordcount MR as follows

hadoop jar WordCount.jar wordcount.WordCountDriver
> s3n://bucket/wordcount/input s3n://bucket/wordcount/output
s3n://bucket/wordcount/input is a s3 object that contains other input files.

However I get following NPE error

12/10/02 18:56:23 INFO mapred.JobClient:  map 0% reduce 0%
> 12/10/02 18:56:54 INFO mapred.JobClient:  map 50% reduce 0%
>         12/10/02 18:56:56 INFO mapred.JobClient: Task Id :
> attempt_201210021853_0001_m_000001_0, Status : FAILED
> java.lang.NullPointerException
>         at
> org.apache.hadoop.fs.s3native.NativeS3FileSystem$NativeS3FsInputStream.close(NativeS3FileSystem.java:106)
>         at java.io.BufferedInputStream.close(BufferedInputStream.java:451)
>         at java.io.FilterInputStream.close(FilterInputStream.java:155)
>         at org.apache.hadoop.util.LineReader.close(LineReader.java:83)
>         at
> org.apache.hadoop.mapreduce.lib.input.LineRecordReader.close(LineRecordReader.java:144)
>         at
> org.apache.hadoop.mapred.MapTask$NewTrackingRecordReader.close(MapTask.java:497)
>         at org.apache.hadoop.mapred.MapTask.runNewMapper(MapTask.java:765)
>         at org.apache.hadoop.mapred.MapTask.run(MapTask.java:370)
>         at org.apache.hadoop.mapred.Child$4.run(Child.java:255)
>         at java.security.AccessController.doPrivileged(Native Method)
>         at javax.security.auth.Subject.doAs(Subject.java:396)
>         at
> org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1121)
>         at org.apache.hadoop.mapred.Child.main(Child.java:249)
MR runs fine if i specify more specific input path such as
s3n://bucket/wordcount/input/file.txt
what i want is to be able to pass s3 folders as parameters
Does anyone knows how to do this?

Best regards,
Ben Kim
On Fri, Jul 20, 2012 at 10:33 AM, Harsh J <[EMAIL PROTECTED]> wrote:

> Dan,
>
> Can you share your error? The plain .gz files (not .tar.gz) are natively
> supported by Hadoop via its GzipCodec, and if you are facing an error, I
> believe its cause of something other than compression.
>
>
> On Fri, Jul 20, 2012 at 6:14 AM, Dan Yi <[EMAIL PROTECTED]> wrote:
>
>> i have a MR job to read file on amazon S3 and process the data on local
>> hdfs. the files are zipped text file as .gz. i tried to setup the job as
>> below but it won't work, anyone know what might be wrong? do i need to add
>> extra step to unzip the file first? thanks.
>>
>> String S3_LOCATION = "s3n://access_key:private_key@bucket_name"
>>
>> protected void prepareHadoopJob() throws Exception {
>>
>>     this.getHadoopJob().setMapperClass(Mapper1.class);
>>     this.getHadoopJob().setInputFormatClass(TextInputFormat.class);
>>
>>     FileInputFormat.addInputPath(this.getHadoopJob(), new Path(S3_LOCATION));
>>
>>     this.getHadoopJob().setNumReduceTasks(0);
>>     this.getHadoopJob().setOutputFormatClass(TableOutputFormat.class);
>>     this.getHadoopJob().getConfiguration().set(TableOutputFormat.OUTPUT_TABLE, myTable.getTableName());
>>     this.getHadoopJob().setOutputKeyClass(ImmutableBytesWritable.class);
>>     this.getHadoopJob().setOutputValueClass(Put.class);
>> }
>>
>>
>>
>>
>> *
>>
>> Dan Yi | Software Engineer, Analytics Engineering
>>   Medio Systems Inc | 701 Pike St. #1500 Seattle, WA 98101
>> Predictive Analytics for a Connected World
>>  *
>>
>>
>
>
> --
> Harsh J
>

--

*Benjamin Kim*
*benkimkimben at gmail*