Hello there,
If you want to connect to a cassandra database with the ruby-filter, you can do it the following way.
All you need for this, is the datastax cassandra ruby driver:
https://github.com/datastax/ruby-driver
Logstash 2.4.0 works on an embedded jruby1.9 and the driver is compatible for this version,
My plan is to install the driver for the embedded jruby version of Logstash. So i run the following commands:
env GEM_HOME=/opt/logstash/vendor/bundle/jruby/1.9 /opt/logstash/vendor/jruby/bin/jruby /opt/logstash/vendor/jruby/bin/gem install cassandra-driver
I hope i could help somebody, who wants to do that =)