Tuesday, May 10, 2016

SolR, NiFi, Twitter and CDH 5.7

Since the most interesting Apache NiFi parts are coming from ASF [1] or Hortonworks [2], I thought to use CDH 5.7 and do the same, just to be curious. Here's now my 30 minutes playground, currently running in Googles Compute.

On one of my playground nodes I installed Apache NiFi per
mkdir /software && cd /software && wget http://mirror.23media.de/apache/nifi/0.6.1/nifi-0.6.1-bin.tar.gz && tar xvfz nifi-0.6.1-bin.tar.gz

Then I've set only nifi.sensitive.props.key property in conf/nifi.properties to an easy to remember secret. The next bash /software/nifi-0.6.1/bin/nifi.sh install installs Apache NiFi as an service. After log in into Apache NiFi's WebUI, download and add the template [3] to Apache NiFi, move the template icon to the drawer, open it and edit the twitter credentials to fit your developer account.

To use an  schema-less SolR index (or Cloudera Search in CDH) I copied some example files over into a local directory:
cp -r /opt/cloudera/parcels/CDH/share/doc/solr-doc-4.10.3+cdh5.7.0+389/example/example-schemaless/solr/collection1/conf/* $HOME/solr_configs/conf/

And added to solrconfig.xml into the <updateRequestProcessorChain name="add-unknown-fields-to-the-schema"> declaration below <updateRequestProcessorChain name="add-unknown-fields-to-the-schema">:
<str>EEE MMM d HH:mm:ss Z yyyy</str>

So it looks like:
<processor>
<arr name="format">
<str>EEE MMM d HH:mm:ss Z yyyy</str>


Since the new Twitter API HTML format the client source, I added a HTML strip processor into the same declaration:

</processor>
  <processor class="solr.HTMLStripFieldUpdateProcessorFactory">
  <str name="fieldName">source_s</str>
</processor>

All configs are available per Gist [4,5].

To get the configs running, initialize SolR:

solrctl --zk ZK_HOST:2181/solr instancedir --create twitter $HOME/solr_configs
solrctl --zk ZK_HOST:2181/solr collection --create twitter -s 2 -c twitter -r 2

Setup Banana for SolR is pretty easy:
cd /software && wget https://github.com/lucidworks/banana/archive/release.zip && unzip release.zip && mv banana-release banana && cp -r banana /opt/cloudera/parcels/CDH/lib/solr/webapps/ on one of the solr hosts and check if it's running per http://solr-node:8983/banana/src/index.html. To move fast forward, I have a dashboard available on gist [5], too.

Screenshot Dashboard:


Apache NiFi flow:


Conclusion
This demo shows that's pretty easy today by using available tools to setup more or less complex data flows within a few hours. Apache NiFi is pretty stable, has a lot of sinks available and runs now 2 weeks in Google Compute, captured over 200 mio tweets and stored them in SolR as well as in HDFS. It's interesting to play around with the data in realtime, interactive driven by Banana.