David Worms

About David Worms

Passionate with programming, data and entrepreneurship, I participate in shaping Adaltas to be a team of talented engineers to share our skills and experiences.

Open Source Summit 2017 – a week in Pragues

The Adaltas crew went to the Open Source Summit 2017 as well as the Mesos Summit 2017 held in Pragues about 3 weeks back. On this occasion, we compiled a series of articles about the conferences that have marked us most. Over the 3-day period of the Open Source Summit, there is no doubt [...]

By |2018-06-05T22:36:44+00:00November 23rd, 2017|Categories: Events|0 Comments

Micro Services

Back in the days, applications were monolithic and we could use an IP address to access a service. With virtual machines (VM), multiple hosts started to appear on the same machine with multiple apps. Things were still similar with VMs and physical machines as services were still accessible from an IP. With MicroServices, things changed [...]

By |2018-06-05T22:36:46+00:00November 14th, 2017|Categories: Open Source Summit Europe 2017|0 Comments

Hive, Calcite and Druid

BI/OLAP requires interactive visualization of complex data streams: Real time bidding events User activity streams Voice call logs Network trafic flows Firewall events Application KPIs Traditionnal solutions RDBMS (Mysql..): don't scale, need caching but adhoc queries remain slow Key/value store (HBase...): quick but takes forever to compute (pre-materialization of data) Context Created in 2011, open-sourced [...]

By |2018-06-05T22:37:07+00:00July 14th, 2016|Categories: Big Data|0 Comments

A simple connect middleware to transpile CoffeeScript files

This new module called connect-coffee-script is a Connect middleware used to serve javascript files written in CoffeeScript. This middleware is to be used by connect or any Connect compatible framework such as Express and Zappa. For those not familiar with CoffeeScript, it is a transpiler which compile into Javascript. […]

By |2018-06-05T22:37:08+00:00July 4th, 2016|Categories: Hack|0 Comments

Catch ‘uncaughtException’ error in your mocha test

This isn't the first time I faced this situation. Today, I finally found the time and energy to look for a solution. In your mocha test, let's say you need to test an expected "uncaughtException" event, the Node.js technique to catch the uncatchable. Easy, just register an "uncaughtException" listener to the process event emitter. Well, [...]

By |2019-02-22T16:38:45+00:00July 27th, 2013|Categories: Hack|0 Comments

Oracle to Apache Hive with the Oracle SQL Connector

In a previous article published last week, I introduced the choices available to connect Oracle and Hadoop. In a follow up article, I covered the Oracle SQL Connector, its installation and integration with Apache Hadoop and more specifically how to declare a file present inside HDFS, the Hadoop filesystem, as a database table inside the [...]

By |2019-02-22T16:33:53+00:00July 27th, 2013|Categories: Big Data|2 Comments

Crawl you website including login form with Phantomjs

With PhantomJS, we start a headless WebKit and pilot it with our own scripts. Said differently, we write a script in JavaScript or CoffeeScript which controls an Internet browser and manipulates the webpage loaded inside. In the past, I've used a similar solution called Selenium. PhantomJS is much faster, it doesn't start a graphical browser [...]

By |2019-02-22T16:31:08+00:00July 27th, 2013|Categories: Hack|0 Comments

Kerberos and delegation tokens security with WebHDFS

WebHDFS is an HTTP Rest server bundle with the latest version of Hadoop. What interests me on this article is to dig into security with the Kerberos and delegation tokens functionalities. I will cover its usages from the command line and a programming language perspective. Don't crawl the web looking for a command to start [...]

By |2019-02-22T16:09:53+00:00July 25th, 2013|Categories: Big Data|0 Comments

Remote connection with SSH

While teaching Big Data and Hadoop, a student asks me about SSH and how to use. I’ll discuss about the protocol and the tools to benefit from it. Lately, I’ve been supervising the deployment of [Hadoop] clusters and its core components including [Kerberos] and [LDAP] servers from a single host to a full [...]

By |2019-02-22T15:54:24+00:00July 24th, 2013|Categories: Hack|0 Comments