charlessimpson / clojure-accumulo-iterators

Use Clojure functions in Apache Accumulo iterators

This package allows Clojure functions to be used in Apache Accumulo iterators.

Installation

Build the package:

mvn package

Copy the package and dependencies to Accumulo's library:

cp ~/.m2/repository/org/clojure/clojure/1.3.0/clojure-1.3.0.jar $ACCUMULO_HOME/lib/ext
cp target/clojure-accumulo-iterators-0.0.1-SNAPSHOT.jar $ACCUMULO_HOME/lib/ext

Usage

The tests in test/main/java give an overview of calling the iterators from Java.

For a quick demonstration, from the Accumulo shell:

createtable foo
insert "a" "" "b" ""
insert "a" "" "c" ""
insert "d" "" "e" ""
setscaniter -p 20 -class clojure_accumulo.iterators.ClojureFilter -n filter
false
(fn [[k v]] (= (str (.getRow k)) "a"))
scan

Versions

This package has been tested against Clojure 1.3.0 and Accumulo 1.4.0. Because Accumulo tends to break its API between minor releases, this package will probably not work with 1.3.5 or 1.5.0, but it should not be difficult to port to either of those versions.