nzkoz / cassandra_object Goto Github PK

Have found that cassandra_object is compatible with cassandra 0.7.6 gem. I have used cassandra_object and cassandra 0.7.6 gem, rails3 beta 3, ruby 1.9.1. At the moment I just get
NameError: uninitialized constant CassandraObject::Base error
although this gems are written in Gemfile.
(CassandraObject class is visible, but CassandraObject::Base is not)

after_create is never being called because the run_callbacks :create .... block always returns false. Patch and crappy test:

http://github.com/tomafro/cassandra_object/commit/467acc99d95b7b37247b39f527dd4bba611e7812

With Gemfile:
gem "rails", '3.0.0.beta'
gem "cassandra_object", :git => "git://github.com/NZKoz/cassandra_object.git"
This works:
IRB> User.new(:nick => 'Tuxie')
#<User:0x4b271f0 @changed_attributes={"nick"=>nil}, @key=nil, @new_record=true, @attributes={"nick"=>"Tuxie"}, @schema_version=0>

But with Gemfile:
gem "rails", :git => "git://github.com/rails/rails.git"
gem "cassandra_object", :git => "git://github.com/NZKoz/cassandra_object.git"
This happens:
IRB> User.new(:nick => 'Tuxie')
NoMethodError: You have a nil object when you didn't expect it!
You might have expected an instance of Array.
The error occurred while evaluating nil.include?
from /home/tuxie/.bundle/ruby/1.8/bundler/gems/rails-16a5e918a06649ffac24fd5873b875daf66212ad-master/activemodel/lib/active_model/dirty.rb:125:in attribute_changed?' from /home/tuxie/.bundle/ruby/1.8/bundler/gems/cassandra_object-13c3c2c8949e63e16c17dc38b03522e12e5a8476-master/lib/cassandra_object/dirty.rb:19:inwrite_attribute'
from /home/tuxie/.bundle/ruby/1.8/bundler/gems/cassandra_object-13c3c2c8949e63e16c17dc38b03522e12e5a8476-master/lib/cassandra_object/attributes.rb:89:in attribute=' from /home/tuxie/.bundle/ruby/1.8/bundler/gems/rails-16a5e918a06649ffac24fd5873b875daf66212ad-master/activemodel/lib/active_model/attribute_methods.rb:262:insend'
from /home/tuxie/.bundle/ruby/1.8/bundler/gems/rails-16a5e918a06649ffac24fd5873b875daf66212ad-master/activemodel/lib/active_model/attribute_methods.rb:262:in nick=' from /home/tuxie/.bundle/ruby/1.8/bundler/gems/cassandra_object-13c3c2c8949e63e16c17dc38b03522e12e5a8476-master/lib/cassandra_object/attributes.rb:74:insend'
from /home/tuxie/.bundle/ruby/1.8/bundler/gems/cassandra_object-13c3c2c8949e63e16c17dc38b03522e12e5a8476-master/lib/cassandra_object/attributes.rb:74:in attributes=' from /home/tuxie/.bundle/ruby/1.8/bundler/gems/cassandra_object-13c3c2c8949e63e16c17dc38b03522e12e5a8476-master/lib/cassandra_object/attributes.rb:73:ineach'
from /home/tuxie/.bundle/ruby/1.8/bundler/gems/cassandra_object-13c3c2c8949e63e16c17dc38b03522e12e5a8476-master/lib/cassandra_object/attributes.rb:73:in attributes=' from /home/tuxie/.bundle/ruby/1.8/bundler/gems/cassandra_object-13c3c2c8949e63e16c17dc38b03522e12e5a8476-master/lib/cassandra_object/base.rb:98:ininitialize'
from (irb):1:in `new'
from (irb):1

Given the following association:

class Zoo < CassandraObject
  association :animals, :unique=>false
end

Reading this association would fail, with an error from the cassandra gem stating 'Required field reversed is unset!'. This is because the reversed option is passed as nil, not false.

Patch: http://github.com/tomafro/cassandra_object/commit/b2b504469c7720eced76aeb24d353a94cc83353c

The readme installation is a bit out of date. Could this be updated?

I'm trying to get the latest version integrated into our app (plus another changeset on my branch) and I'm getting this:

CassandraStatus
NameError: uninitialized constant ActiveSupport::Callbacks
from /Users/ryan/code/twitter/vendor/rails/activerecord/lib/../../activesupport/lib/active_support/dependencies.rb:263:in load_missing_constant' from /Users/ryan/code/twitter/vendor/rails/activerecord/lib/../../activesupport/lib/active_support/dependencies.rb:453:inconst_missing_not_from_s3_library'
from /Users/ryan/code/twitter/vendor/gems/aws-s3-0.6.2/lib/aws/s3/extensions.rb:206:in const_missing' from /Users/ryan/code/twitter/vendor/gems/cassandra_object/lib/cassandra_object/legacy_callbacks.rb:4 from /opt/ruby-enterprise-1.8.7-2009.10/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:ingem_original_require'
from /opt/ruby-enterprise-1.8.7-2009.10/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in require' from /Users/ryan/code/twitter/vendor/rails/activerecord/lib/../../activesupport/lib/active_support/dependencies.rb:496:inrequire'
from /Users/ryan/code/twitter/vendor/rails/activerecord/lib/../../activesupport/lib/active_support/dependencies.rb:342:in new_constants_in' from /Users/ryan/code/twitter/vendor/rails/activerecord/lib/../../activesupport/lib/active_support/dependencies.rb:496:inrequire'
from /Users/ryan/code/twitter/vendor/gems/cassandra_object/lib/cassandra_object/base.rb:8
from /opt/ruby-enterprise-1.8.7-2009.10/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in gem_original_require' from /opt/ruby-enterprise-1.8.7-2009.10/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:inrequire'
from /Users/ryan/code/twitter/vendor/rails/activerecord/lib/../../activesupport/lib/active_support/dependencies.rb:496:in require' from /Users/ryan/code/twitter/vendor/rails/activerecord/lib/../../activesupport/lib/active_support/dependencies.rb:342:innew_constants_in'
from /Users/ryan/code/twitter/vendor/rails/activerecord/lib/../../activesupport/lib/active_support/dependencies.rb:496:in require' from /Users/ryan/code/twitter/vendor/gems/cassandra_object/lib/cassandra_object.rb:28 from /opt/ruby-enterprise-1.8.7-2009.10/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:ingem_original_require'
from /opt/ruby-enterprise-1.8.7-2009.10/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in require' from /Users/ryan/code/twitter/vendor/rails/activerecord/lib/../../activesupport/lib/active_support/dependencies.rb:496:inrequire'
from /Users/ryan/code/twitter/vendor/rails/activerecord/lib/../../activesupport/lib/active_support/dependencies.rb:342:in new_constants_in' from /Users/ryan/code/twitter/vendor/rails/activerecord/lib/../../activesupport/lib/active_support/dependencies.rb:496:inrequire'
from /Users/ryan/code/twitter/app/models/cassandra_status.rb:1
from /Users/ryan/code/twitter/vendor/rails/activerecord/lib/../../activesupport/lib/active_support/dependencies.rb:203:in load_without_new_constant_marking' from /Users/ryan/code/twitter/vendor/rails/activerecord/lib/../../activesupport/lib/active_support/dependencies.rb:203:inload_file'
from /Users/ryan/code/twitter/vendor/rails/activerecord/lib/../../activesupport/lib/active_support/dependencies.rb:342:in new_constants_in' from /Users/ryan/code/twitter/vendor/rails/activerecord/lib/../../activesupport/lib/active_support/dependencies.rb:202:inload_file'
from /Users/ryan/code/twitter/vendor/rails/activerecord/lib/../../activesupport/lib/active_support/dependencies.rb:94:in require_or_load' from /Users/ryan/code/twitter/vendor/rails/activerecord/lib/../../activesupport/lib/active_support/dependencies.rb:248:inload_missing_constant'
from /Users/ryan/code/twitter/vendor/rails/activerecord/lib/../../activesupport/lib/active_support/dependencies.rb:453:in const_missing_not_from_s3_library' from /Users/ryan/code/twitter/vendor/gems/aws-s3-0.6.2/lib/aws/s3/extensions.rb:206:inconst_missing'
from /Users/ryan/code/twitter/vendor/rails/activerecord/lib/../../activesupport/lib/active_support/dependencies.rb:465:in `const_missing'
from (irb):2>>

In the first example there is index :date_of_birth string. How will this influence Cassandra database? What additional queries will I be able to make?

Is there some ability to use full text search with Cassandra object?

Currently, accessing an association (such as customer.invoices) throws an exception if the association is empty. Here's a patch to stop that happening:

http://github.com/tomafro/cassandra_object/commit/d2bb3fa1b19a9cabf01ce1606d6f1fcb67817127

Seems like cassandra gem has no Cassandra::UUID class. I replaced it with SimpleUUID::UUID and I could require cassandra and cassandra_object without errors. But then when I created class inherited from CassandraObject::Base and tried to create new user instance with some parameters: User.new(:first_name => "name"), I got error:

irb(main):020:0> User.new(:first_name => "name")
NoMethodError: undefined method 'encode' for nil:NilClass
from /home/ras/Programming/NoSQL/cassandra_object/lib/cassandra_object/attributes.rb:14:in `check_value!'
from /home/ras/Programming/NoSQL/cassandra_object/lib/cassandra_object/attributes.rb:62:in `write_attribute'
from /home/ras/Programming/NoSQL/cassandra_object/lib/cassandra_object/dirty.rb:23:in `write_attribute'
from /home/ras/Programming/NoSQL/cassandra_object/lib/cassandra_object/attributes.rb:89:in `attribute='
from /usr/local/lib/ruby/gems/1.9.1/gems/activemodel-3.0.0.beta3/lib/active_model/attribute_methods.rb:273:in `first_name='
from /home/ras/Programming/NoSQL/cassandra_object/lib/cassandra_object/attributes.rb:74:in `block in attributes='
from /home/ras/Programming/NoSQL/cassandra_object/lib/cassandra_object/attributes.rb:73:in `each'
from /home/ras/Programming/NoSQL/cassandra_object/lib/cassandra_object/attributes.rb:73:in `attributes='
from /home/ras/Programming/NoSQL/cassandra_object/lib/cassandra_object/base.rb:98:in `initialize'
from (irb):20:in `new'
from (irb):20
from /usr/local/bin/irb:12:in '<main>'

although :first_name attribute was set in User class.
I was using ruby 1.9.1, rails3 beta3, cassandra 0.8.2 gem, cassandra 0.6.

Because there is not get_key_range method at there.

Running the newest Cassandra Beta (0.6 Beta 3) in combination with the HEAD of the Cassandra Ruby Library, querying for "all" objects returns "nil" objects.

Currently, the get_range() function returns on ore more columns wrapped into "CassandraThrift::KeySlice" objects. The current implementation expects the columns keys as return values.

The added patch fixes this problem by "getting" the key from the retrieved object. For compatibility with older versions, maybe check the version of the libraries and act appropriately (as type checking is too costly)?

http://gist.github.com/340381

I was wondering why attributes can't be of type :boolean. I was looking in 'lib/types.rb' and found a BooleanType but it wasn't registered in 'lib/type_registration.rb'. Was this intentional?

Thanks!

If I am planning to use Cassandra, but in my application I have different kinds of filters - by status, by project, by user and so on. As I know - cassandra_object (as well as Cassandra itself) has no support of :conditions statement. The only way to avoid this problem is to write indexes of all this information just as you put some new values. Can anybody suggest some best practices about storing such information?

uninitialized constant Cassandra::UUID error, on Cassandra Gem >= 0.7.6.

This patch use SimpleUUID::UUID instead of Cassandra::UUID:

http://github.com/jusnavigandi/cassandra_object/commit/d6e898ce243de8ff5bb52871089d6efc70651342