cassandra_client

A client for the Cassandra distributed database.

License

Copyright 2009 Twitter, Inc. See included LICENSE file. Portions copyright 2004-2009 David Heinemeier Hansson, and used with permission.

The public certificate for this gem is here.

Features

• clean encapsulation of the Thrift API

• pluggable serialization and compression

• Ruby 1.9 compatibility

This is an alpha release and does not yet support the full Thrift API.

Cassandra is a rapidly moving target; this library is currently tested againt Cassandra trunk revision 789419.

Installation

You need Ruby 1.8 or 1.9, and Thrift.

If you don’t want to install Thrift from source, you can use this pre-packaged gem. Once you have Thrift, just run:

sudo gem install cassandra_client

Usage

Require the library:

require 'cassandra_client'

Connect to a server:

client = CassandraClient.new("127.0.0.1")

Get a keyspace:

users = client.table('Users')

Insert into a column family. You can insert a CassandraClient::OrderedHash, or a regular Hash, if order doesn’t matter:

users.insert("5", :row, {'screen_name' => "buttonscat"})

Insert into a super column family:

users.insert("5", :relationships, {"user_timeline" => {"1" => ""}})

Query a super column:

timeline = users.get("5", :relationships, "user_timeline")

The returned result will always be a CassandraClient::OrderedHash.

See CassandraClient::Table for more methods.

Reporting problems

The Github issue tracker is here. If you have problems with Cassandra itself, please use the cassandra-user mailing list.

Patches and contributions are very welcome. Please note that contributors are required to assign copyright for their additions to Twitter, Inc.