active_redis_orm

ActiveRedis

Installation

Add this line to your application's Gemfile:

gem 'active_redis_orm'

And then execute:

$ bundle

Or install it yourself as:

$ gem install active_redis_orm

Usage

In an initializer, make sure that you're using the correct connection:

ActiveRedis.redis = Redis.new(connection_details)

Creating an ActiveRedis class looks like a combination of ActiveRecord and Mongoid:

class User < ActiveRedis::Base
  field :username, finder_field: true
  field :name
  field :birthday, type: :date
  field :age, type: :integer, default: lambda{|user| user.age_from_birthday}
  field :things, type: :set
end

Declaring fields is similar to Mongoid - you declare the field, and its type (the default is string). We use symbols for type, unlike Mongoid which uses the data type's class.

Available types are: :string, :set, :sorted_set, :list, :hash, :float, :integer (or :int), :counter, :boolean, :date, :time (or :datetime, :timestamp).

You can declare a default value with either a value or a lambda.

Finder Fields

When you want to be able to find an object by something other than its ID, you can define an index by stating a field to be a finder_field. This will allow you to do this:

User.create(username: "some_guy")

User.find_by_username("some_guy") #=> our user

When finding by ID, returns the object or nil. By default, every ActiveRedis class has a #presence_field method which is defaulted to "1", you can override the need for this if you have another way to determine presence (i.e. another field which says "this object surely exists"), in which case, override the "presence_field" class variable:

class User < ActiveRedis::Base
  field :name

  self.presence_field = :name
end

This way the #present? method on User will call the name method and check if it's present.

Redis Data Structures

Using hashes, sets, sorted sets and lists is simple-ish.

Hash simply acts like a hash

Sets and Lists act like any ruby array

Sorted sets' getters act as an array, but setters are hash-like, where the hash key is the value and hash value is the score. Yes, it's a bit confusing.

class User < ActiveRedis::Base
  field :foo, type: :sorted_set
end

user = User.new

user.foo["value2"] = 1

user.foo["value1"] = 0
user.save

user.foo #=> ["value1", "value2"]

Callbacks and Validations

Callbacks and validations work just like in Mongoid or ActiveRecord

class Messages < ActiveRedis::Base
  include ActiveRedis::Timestamps

  field :text
  field :user_id

  validates :text, presence: true, length: {maximum: 256}
  validates :user_id, presence: true

  after_create :do_something

  def do_something
    #this gets called after create
  end
end

message = Message.new(text: "I am new text")
message.save #=> false

message.errors.messages #=> {:user_id=>["can't be blank"]}

available callbacks are before/after/around for create/update/save

available validations are any validations which come with ActiveModel (we're still missing the uniqueness validation, as it's a problem in redis, but it'll happen)

Contributing

1. Fork it ( http://github.com//active_redis_orm/fork )
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create new Pull Request