Redis Classy
Class-style namespace prefixing for Redis.
With Redis Classy, class names become the prefix part of the Redis keys.
class Something < Redis::Classy
end
Something.set "foo", "bar" # equivalent of => redis.set "Something:foo", "bar"
Something.get "foo" # => redis.get "Something:foo"
=> "bar"
This library contains only 33 lines of code, yet powerful when you need better abstraction on Redis objects to keep things organized.
Requies the redis-namespace
gem.
What's new:
- v1.0.0: Play nice with Mongoid
Synopsis
With the vanilla redis gem, you've been doing this:
redis = Redis.new
redis.set "foo", "bar"
With the redis-namespace gem, you can add a prefix in the following manner:
redis_ns = Redis::Namespace.new('ns', :redis => redis)
redis_ns['foo'] = 'bar' # equivalent of => redis.set "ns:foo", "bar"
Now, with the redis-classy gem, you could finally do:
class Something < Redis::Classy
end
Something.set "foo", "bar" # equivalent of => redis.set "Prefix:foo", "bar"
Something.get "foo"
=> "bar"
Install
gem install redis-classy
Usage
In Gemfile:
gem "redis-classy"
In config/initializers/redis_classy.rb:
Redis::Classy.db = Redis.new
Now you can write models that inherit the Redis::Classy class, automatically prefixing keys with its class name. You can use any Redis commands on the class, since they are simply passed to the Redis instance.
class UniqueUser < Redis::Classy
def self.nuke
self.keys.each{|key| self.del(key) }
end
end
UniqueUser.sadd "2011-02-28", @user_a.id
UniqueUser.sadd "2011-02-28", @user_b.id
UniqueUser.sadd "2011-03-01", @user_c.id
UniqueUser.smembers "2011-02-28"
=> ["123", "456"]
UniqueUser.nuke
=> ["2011-02-28", "2011-03-01"]
UniqueUser.keys
=> []
In most cases you may be just fine with class methods, but by creating an instance with a key, even further binding is possible.
class Counter < Redis::Classy
def initialize(object)
super("#{object.class.name}:#{object.id}")
end
end
class Room < ActiveRecord::Base
end
@room = Room.create
counter = Counter.new(@room)
counter.incr
counter.incr
counter.get
=> "2"
counter.key
=> "Room:123"
You also have access to the non-namespaced, raw Redis instance via Redis::Classy
Redis::Classy.keys "UniqueUser:*"
=> ["UniqueUser:2011-02-28", "UniqueUser:2011-03-01"]
Redis::Classy.multi do
UniqueUser.sadd "2011-02-28", @user_a.id
UniqueUser.sadd "2011-02-28", @user_b.id
end
Since the "db" attribute is a class instance variable, you can dynamically assign different databases for each class.
UniqueUser.db = Redis::Namespace.new("UniqueUser", :redis => Redis.new(:host => "another.host"))
Reference
Dependency:
Use case: