Skip to main content

SolR, NiFi, Twitter and CDH 5.7

Listen:

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. 





Comments

Popular posts from this blog

Beyond Ctrl+F - Use LLM's For PDF Analysis

PDFs are everywhere, seemingly indestructible, and present in our daily lives at all thinkable and unthinkable positions. We've all got mountains of them, and even companies shouting about "digital transformation" haven't managed to escape their clutches. Now, I'm a product guy, not a document management guru. But I started thinking: if PDFs are omnipresent in our existence, why not throw some cutting-edge AI at the problem? Maybe Large Language Models (LLMs) and Retrieval Augmented Generation (RAG) could be the answer. Don't get me wrong, PDF search indexes like Solr exist, but they're basically glorified Ctrl+F. They point you to the right file, but don't actually help you understand what's in it. And sure, Microsoft Fabric's got some fancy PDF Q&A stuff, but it's a complex beast with a hefty price tag. That's why I decided to experiment with LLMs and RAG. My idea? An intelligent knowledge base built on top of our existing P...

Deal with corrupted messages in Apache Kafka

Under some strange circumstances, it can happen that a message in a Kafka topic is corrupted. This often happens when using 3rd party frameworks with Kafka. In addition, Kafka < 0.9 does not have a lock on Log.read() at the consumer read level, but does have a lock on Log.write(). This can lead to a rare race condition as described in KAKFA-2477 [1]. A likely log entry looks like this: ERROR Error processing message, stopping consumer: (kafka.tools.ConsoleConsumer$) kafka.message.InvalidMessageException: Message is corrupt (stored crc = xxxxxxxxxx, computed crc = yyyyyyyyyy Kafka-Tools Kafka stores the offset of each consumer in Zookeeper. To read the offsets, Kafka provides handy tools [2]. But you can also use zkCli.sh, at least to display the consumer and the stored offsets. First we need to find the consumer for a topic (> Kafka 0.9): bin/kafka-consumer-groups.sh --zookeeper management01:2181 --describe --group test Prior to Kafka 0.9, the only way to get this in...

What Makes You The Number 1 Product Manager?

Amazon often does this thing where they start with the customer instead of just coming up with a product and then trying to figure out how to sell it. They call it " working backwards. " This strategy totally works for any product decisions, but it's especially important when they're making something new. The Press Release Exercise When it comes to launching new stuff, product managers usually start by writing a press release for customers. This press release is all about their pain points, how current solutions fall short, and how the new product is going to crush it. If the benefits don't get customers excited, the product manager needs to keep tweaking the press release until it sounds super awesome. It's way easier and cheaper to make changes to a press release than it is to change the product itself. Here’s a template I use to describe a new service or product: Main heade r: The product name anyone directly understands, like “Ultra-compact power charger” ...