Quieter Cascalog
Tonight I attended a meetup on Cascalog, a clojure DSL built on top of the Hadoop map-reduce framework. (Slides here and code here if you’d like to check it out yourself).
Running huge, complicated queries with a few lines of code was
awesome, but my Hadoop installation made a lot of noise whenever I
tried a query in the REPL using the ?<-
query executor, printing
lots of unwanted log info to
stdout. (I was using Hadoop
installed over homebrew
instead of the
readme
recommendation).
Fortunately, it’s easy to
hush the logger a little by
running queries inside
cascalog.io/with-log-level
.
Here’s a quick two-line
macro that wraps calls to
?<-
in with-log-level
to
quiet down Hadoop:
(require '[cascalog.io :refer [with-log-level]])
(defmacro ?<-- [& forms] `(with-log-level :fatal (?<- ~@forms)))
For future reference, you can find a gist here.