Running Apache Pig Scripts from Apache NiFi and Storing the Results in HDFS

[#1]

Starting My Hadoop Tools

NiFi can interface directly with Hive, HDFS, HBase, Flume and Phoenix. And I can also trigger Spark and Flink through Kafka and Site-To-Site. Sometimes I need to run some Pig scripts. Apache Pig is very stable and has a lot of functions and tools that make for some smart processing. You can easily augment and add this piece to a larger pipeline or part of the process.

Pig Setup

I like to use Ambari to install the HDP 2.5 clients on my NiFi box to have access to all the tools I may need.

Then I can just do:

yum install pig

Pig to Apache NiFi 1.0.0

ExecuteProcess

We call a shell script that wraps the Pig script.

Output of script is stored to HDFS: hdfs dfs -ls /nifi-logs

Shell Script

export JAVA_HOME=/opt/jdk1.8.0_101/ 
pig -x local -l /tmp/pig.log -f /opt/demo/pigscripts/test.pig

You can run in different Pig modes like local, mapreduce and tez. You can also pass in parameters or the script.

Pig Script

messages = LOAD '/opt/demo/HDF/centos7/tars/nifi/nifi-1.0.0.2.0.0.0-579/logs/nifi-app.log';
warns = FILTER messages BY $0 MATCHES '.*WARN+.*';
DUMP warns
store warns into 'warns.out'

This is a basic example from the internet, with the NIFI 1.0 log used as the source.

As an aside, I run a daily script with the schedule 1 * * * * ? to clean up my logs.

Simply: /bin/rm -rf /opt/demo/HDF/centos7/tars/nifi/nifi-1.0.0.2.0.0.0-579/logs/*2016*

PutHDFS

Hadoop Configuration: /etc/hadoop/conf/core-site.xml

Pick a directory and store away.

Results

HadoopVersionPigVersionUserIdStartedAtFinishedAtFeatures
2.7.3.2.5.0.0-12450.16.0.2.5.0.0-1245root2016-11-03 19:53:572016-11-03 19:53:59FILTER
Success!
Job Stats (time in seconds):
JobIdMapsReducesMaxMapTimeMinMapTimeAvgMapTimeMedianMapTimeMaxReduceTimeMinReduceTimeAvgReduceTimeMedianReducetimeAliasFeatureOutputs
job_local72884441_000110n/an/an/an/a0000messages,warnsMAP_ONLYfile:/tmp/temp1540654561/tmp-600070101,
Input(s):
Successfully read 30469 records from: "/opt/demo/HDF/centos7/tars/nifi/nifi-1.0.0.2.0.0.0-579/logs/nifi-app.log"
Output(s):
Successfully stored 1347 records in: "file:/tmp/temp1540654561/tmp-600070101"
Counters:
Total records written : 1347
Total bytes written : 0
Spillable Memory Manager spill count : 0
Total bags proactively spilled: 0
Total records proactively spilled: 0
Job DAG:
job_local72884441_0001

Reference:

• http://hortonworks.com/hadoop-tutorial/hello-world-an-introduction-to-hadoop-hcatalog-hive-and-pig/#...
• http://hortonworks.com/apache/pig/#section_2
• http://hortonworks.com/blog/jsonize-anything-in-pig-with-tojson/
• https://github.com/dbist/pig
• https://github.com/sudar/pig-samples
• http://hortonworks.com/hadoop-tutorial/how-to-use-basic-pig-commands/
• http://hadooptutorial.info/built-in-load-store-functions-in-pig/
• https://cwiki.apache.org/confluence/display/PIG/PigTutorial
• https://docs.hortonworks.com/HDPDocuments/HDP2/HDP-2.4.3/bk_installing_manually_book/content/validat...
• http://pig.apache.org/docs/r0.16.0/start.html
• http://hortonworks.com/hadoop-tutorial/how-to-process-data-with-apache-pig
• https://github.com/alanfgates/programmingpig/tree/master/examples/ch2