lytol / redistry

A set of useful Redis patterns/abstractions for Ruby (and Rails)

Getting Started

Rails 3

Add redistry to your Gemfile

gem "redistry"

You can also use your own redis client connection rather than the default Redis.new (in an initializer, for example)

Redistry.client = Redis.new(:host => 'my-redis-host', :port => 6379)

Using has_list

Associate a Redis list with each ActiveRecord item:

class Notification < ActiveRecord::Base

end

...

class User < ActiveRecord::Base
  has_list :recent_notifications, :class => Notification, :size => 10

  ...
end

You can add items to the list with add:

user.recent_notifications.add(notification)

Since you specified :size, Redistry will treat the list as a queue (first in, last out) with a maximum of size elements. If you don't specify :size, the list will not limit the size at all.

You can fetch the items with all:

@notifications = user.recent_notifications.all

And you can clear all the notifications with clear:

user.recent_notifications.clear

Using list

Sometimes, you want to associate a list generically with an entire class (or a module)

class User
  list :popular, :size => 10
  ...
end

Note that since we didn't specify :class, Redistry will assume the objects are of the same type as the outer class (in this case, User).

Use the same interface as has_list to access the items:

User.popular.add(@user)
@popular_users = User.popular.all
User.popular.clear

Known Issues / TODO

• JSON serializer does not work with strings... not sure how to deal since this technically is not valid json

Copyright (c) 2011 Brian Smith ([email protected])