Most interesting links of October ’12

Recommended Readings David Veksler: Some lesser-known truths about programming – things newcomers into the field of IT don’t know and don’t expect, true and an interesting read. Not backed by good data but anyway. F.ex.: “[..] a programmer spends about 10-20% of his time writing code [..] much of the other 90% thinking, researching, andContinue reading “Most interesting links of October ’12”

Do You Know Why You Are Testing?! (On The Principles Underlying TDD)

Kent Beck in his recent post Functional TDD: A Clash of Cultures summarizes well the key principles and benefits that underlie test-driven development. I think it is really worthwhile becoming aware of and thinking over these foundation stones of TDD (and testing in general). Knowing them enables you to apply TDD in the most effectiveContinue reading “Do You Know Why You Are Testing?! (On The Principles Underlying TDD)”

Tip: Import Leiningen Project to IntelliJ (With Dependencies)

To import a Leiningen-based project into IntelliJ with the Clojure plugin, the best way seems to be: Run lein pom to generate a Maven pom.xml from project.clj Import the project as a Maven project (File – New Project… – Import project from external model – Maven – browse to the directory – …) Versions: LeiningenContinue reading “Tip: Import Leiningen Project to IntelliJ (With Dependencies)”

Tool Tip: Byob – Screen With Text UI

Screen (man) is very useful for running terminal sessions on remote computers that enable the user to disconnect and re-connect. Byobu (man), formerly also called screen-profiles, is a wrapper script for screen that adds status lines with useful info to screen and provides text UI for configuring it (byobu-config). Screen allows you to have multipleContinue reading “Tool Tip: Byob – Screen With Text UI”

Puppet Troubleshooting: Compiling Catalog, Locating a Cached Catalog

Few troubleshooting tips for Puppet. Where to Find the Cached Catalog On Client Puppet Agent caches its compiled (text/Ruby) catalog under its $vardir, for example Puppet 0.25.x stores it into /var/lib/puppet/client_yaml/catalog/<hostname>.yaml. It might be useful when troubleshooting. Compiling Catalog Manually You can compile the catalog for a particular node manually on the Puppet Master. Ex.:Continue reading “Puppet Troubleshooting: Compiling Catalog, Locating a Cached Catalog”

My Scala vs. Clojure Impression In Pictures

(By kristobalite) Clojure: Clean Structured Focused (By agiamba) Scala: Adorned Overflowing Magnificent Clojure has a zen-like quality to it. There is extreme focus on simplicity, on defining few elementary orthogonal concepts that can be combined in powerful ways. For example it took 3 years for Clojure to get named parameters – but the result, destructuring,Continue reading “My Scala vs. Clojure Impression In Pictures”

Note: Loading Tab-Separated Data In Cascalog

To load all fields from a tab-separated text file in Cascalog we need to use the generic hfs-tap and specify the “scheme” (notice that loading all fields and expecting tab as the separator is the default behavior of TextDelimited): With a custom separator and fields: Hadoop doesn’t manage to load data files from nested sub-directoriesContinue reading “Note: Loading Tab-Separated Data In Cascalog”