cassandra_object_rails

== Cassandra Object Rails

Cassandra Object uses ActiveModel to mimic much of the behavior in ActiveRecord.

=== Installation

Add the following to your Gemfile:

gem 'cassandra_object_rails'

=== Defining Models

class Widget < CassandraObject::Base string :name string :description integer :price array :colors, unique: true

validates :name, presence: :true

before_create do
  self.description = "#{name} is the best product ever"
end

end

=== Connecting to the Server

CassandraObject::Base.config = { keyspace: 'my_app_development', servers: '127.0.0.1:9160', thrift: { timeout: 20, retries: 2 } }

=== Connecting your rails application with Cassandra

in your config/cassandra.yml

development: keyspace: 'my_app_development' servers: '127.0.0.1:9160'

test: keyspace: 'my_app_development' servers: '127.0.0.1:9160'

production: keyspace: 'my_app_development' servers: '127.0.0.1:9160'

=== Creating and updating records

Cassandra Object has equivalent methods as ActiveRecord:

widget = Widget.new widget.valid? widget = Widget.create(name: 'Acme', price: 100) widget.update_attribute(:price, 1200) widget.update_attributes(price: 1200, name: 'Acme Corporation') widget.attributes = {price: 300} widget.price_was widget.save widget.save!

=== Finding records

widget = Widget.find(uuid) widget = Widget.first widgets = Widget.all Widget.find_each do |widget| ... end

=== Query

Some lightweight scoping features are available:

Widget.where('color' => 'red') Widget.select(['name', 'color']) Widget.limit(10)

=== Keyspace

Creating cassandra keyspace defined on cassandra.yml

rake cassandra:create

Droping cassandra keyspace

rake cassandra:drop

=== Adding column family

CassandraObject::Schema.create_column_family 'Widgets'