Acts As Saveable (aka Favorite Lists)

Favorite Lists is a Ruby Gem specifically written for Rails/ActiveRecord models. The main goals of this gem are:

Allow any model to be saved on, like/dislike, upsaved/downsaved, for later reading and viewing etc.
Allow any model to be saved under arbitrary scopes.
Allow any model to saved. In other words, saves do not have to come from a user, they can come from any model (such as a Group or Team).
Provide an easy to write/read syntax.

Installation

Supported Ruby and Rails versions

Ruby 1.8.7, 1.9.2, 1.9.3
Ruby 2.0.0, 2.1.0
Rails 3.0, 3.1, 3.2
Rails 4.0, 4.1+

Install

Just add the following to your Gemfile.

gem 'acts_as_saveable', '~> 0.10.1'

And follow that up with a bundle install.

Database Migrations

Acts As Saveable uses a saves table to store all saving information. To generate and run the migration just use.

rails generate acts_as_saveable:migration
rake db:migrate

You will get a performance increase by adding in cached columns to your model's tables. You will have to do this manually through your own migrations. See the caching section of this document for more information.

Usage

Saveable Models

class Post < ActiveRecord::Base
  acts_as_saveable
end

@post = Post.new(:name => 'my post!')
@post.save

@post.upsaved_by @user
@post.saves_for.size # => 1

Like/Dislike Yes/No Up/Down

Here are some saving examples. All of these calls are valid and acceptable. The more natural calls are the first few examples.

@post.upsaved_by @user1
@post.downsave_from @user2
@post.save_by :saver => @user3
@post.save_by :saver => @user4, :saved => 'bad'
@post.save_by :saver => @user5, :saved => 'like'

By default all saves are positive, so @user3 has cast a 'good' saved for @post.

@user1, @user3, and @user5 all saved in favor of @post.

@user2 and @user4 on the other had has saved against @post.

Just about any word works for casting a saved in favor or against post. Up/Down, Like/Dislike, Positive/Negative... the list goes on-and-on. Boolean flags true and false are also applicable.

Revisiting the previous example of code.

# positive saves
@post.upsaved_by @user1
@post.save_by :saver => @user3
@post.save_by :saver => @user5, :saved => 'like'

# negative saves
@post.downsave_from @user2
@post.save_by :saver => @user2, :saved => 'bad'

# tally them up!
@post.saves_for.size # => 5
@post.get_upsaves.size # => 3
@post.get_downsaves.size # => 2

Active Record scopes are provided to make life easier.

@post.saves_for.up.by_type(User)
@post.saves_for.down
@user1.saves.up
@user1.saves.down
@user1.saves.up.by_type(Post)

Once scoping is complete, you can also trigger a get for the saver/saveable

@post.saves_for.up.by_type(User).savers
@post.saves_for.down.by_type(User).savers

@user.saves.up.for_type(Post).saveables
@user.saves.up.saveables

You can also 'unsaved' a model to remove a previous saved.

@post.upsaved_by @user1
@post.unsaved_by @user1

Unsaving works for both positive and negative saves.

Examples with scopes

You can add a scope to your saved

# positive saves
@post.upsaved_by @user1, :save_scope => 'rank'
@post.save_by :saver => @user3, :save_scope => 'rank'
@post.save_by :saver => @user5, :saved => 'like', :save_scope => 'rank'

# negative saves
@post.downsave_from @user2, :save_scope => 'rank'
@post.save_by :saver => @user2, :saved => 'bad', :save_scope => 'rank'

# tally them up!
@post.find_saves_for(:save_scope => 'rank').size # => 5
@post.get_upsaves(:save_scope => 'rank').size # => 3
@post.get_downsaves(:save_scope => 'rank').size # => 2

# saveable model can be saved under different scopes
# by the same user
@post.save_by :saver => @user1, :save_scope => 'week'
@post.save_by :saver => @user1, :save_scope => 'month'

@post.saves_for.size # => 2
@post.find_saves_for(:save_scope => 'week').size # => 1
@post.find_saves_for(:save_scope => 'month').size # => 1

Adding weights to your saves

You can add weight to your saved. The default value is 1.

# positive saves
@post.upsaved_by @user1, :save_weight => 1
@post.save_by :saver => @user3, :save_weight => 2
@post.save_by :saver => @user5, :saved => 'like', :save_scope => 'rank', :save_weight => 3

# negative saves
@post.downsave_from @user2, :save_scope => 'rank', :save_weight => 1
@post.save_by :saver => @user2, :saved => 'bad', :save_scope => 'rank', :save_weight => 3

# tally them up!
@post.find_saves_for(:save_scope => 'rank').sum(:save_weight) # => 6
@post.get_upsaves(:save_scope => 'rank').sum(:save_weight) # => 6
@post.get_downsaves(:save_scope => 'rank').sum(:save_weight) # => 4

The Saver

You can have your savers acts_as_saver to provide some reserve functionality.

class User < ActiveRecord::Base
  acts_as_saver
end


@article.saves.size # => 1

To check if a saver has saved on a model, you can use saved_for?. You can check how the saver saved by using saved_as_when_saved_for.

@user.up_saves @comment2
# user has not saved on @comment3

@user.saved_for? @comment1 # => true
@user.saved_for? @comment2 # => true
@user.saved_for? @comment3 # => false

@user.saved_as_when_saved_for @comment1 # => true, he liked it
@user.saved_as_when_saved_for @comment2 # => false, he didnt like it
@user.saved_as_when_saved_for @comment3 # => nil, he has yet to saved

You can also check whether the saver has saved up or down.

@user.saves @comment1
# user has not saved on @comment3

@user.saved_up_on? @comment1 # => true
@user.saved_down_on? @comment1 # => false

@user.saved_down_on? @comment2 # => true
@user.saved_up_on? @comment2 # => false

@user.saved_up_on? @comment3 # => false
@user.saved_down_on? @comment3 # => false

Aliases for methods saved_up_on? and saved_down_on? are: saved_up_for?, saved_down_for?.

Also, you can obtain a list of all the objects a user has saved for. This returns the actual objects instead of instances of the Vote model. All objects are eager loaded

@user.find_saved_items

@user.find_up_saved_items

@user.find_down_saved_items

Members of an individual model that a user has saved for can also be displayed. The result is an ActiveRecord Relation.

@user.get_saved Comment

@user.get_up_saved Comment

@user.get_down_saved Comment

Registered Votes

Savers can only saved once per model. In this example the 2nd saved does not count because @user has already saved for @shoe.

@user.save_up_for @shoe
@user.save_up_for @shoe

@shoe.saves # => 1
@shoe.save_up_for # => 1

To check if a saved counted, or registered, use save_registered? on your model after saving. For example:

@hat.upsaved_by @user
@hat.save_registered? # => true

@hat.upsaved_by => @user
@hat.save_registered? # => false, because @user has already saved this way

@hat.dissaved_by @user
@hat.save_registered? # => true, because user changed their saved

@hat.saves.size # => 1
@hat.positives.size # => 0
@hat.negatives.size # => 1

To permit duplicates entries of a same saver, use option duplicate. Also notice that this will limit some other methods that didn't deal with multiples saves, in this case, the last saved will be considered.

@hat.save_by saver: @user, :duplicate => true

Caching

To speed up perform you can add cache columns to your saveable model's table. These columns will automatically be updated after each saved. For example, if we wanted to speed up @post we would use the following migration:

class AddCachedVotesToPosts < ActiveRecord::Migration
  def self.up
    add_column :posts, :cached_saves_total, :integer, :default => 0
    add_column :posts, :cached_saves_score, :integer, :default => 0
    add_column :posts, :cached_saves_up, :integer, :default => 0
    add_column :posts, :cached_saves_down, :integer, :default => 0
    add_column :posts, :cached_weighted_score, :integer, :default => 0
    add_column :posts, :cached_weighted_total, :integer, :default => 0
    add_column :posts, :cached_weighted_average, :float, :default => 0.0
    add_index  :posts, :cached_saves_total
    add_index  :posts, :cached_saves_score
    add_index  :posts, :cached_saves_up
    add_index  :posts, :cached_saves_down
    add_index  :posts, :cached_weighted_score
    add_index  :posts, :cached_weighted_total
    add_index  :posts, :cached_weighted_average

    # Uncomment this line to force caching of existing saves
    # Post.find_each(&:update_cached_saves)
  end

  def self.down
    remove_column :posts, :cached_saves_total
    remove_column :posts, :cached_saves_score
    remove_column :posts, :cached_saves_up
    remove_column :posts, :cached_saves_down
    remove_column :posts, :cached_weighted_score
    remove_column :posts, :cached_weighted_total
    remove_column :posts, :cached_weighted_average
  end
end

cached_weighted_average can be helpful for a rating system, e.g.:

Order by average rating:

Post.order(:cached_weighted_average => :desc)

Display average rating:

<%= post.weighted_average.round(2) %> / 5
<!-- 3.5 / 5 -->

Testing

All tests follow the RSpec format and are located in the spec directory. They can be run with:

rake spec

Changes

Fixes for saveable saver model

In version 0.8.0, there are bugs for a model that is both saveable and saver.
Some name-conflicting methods are renamed:

Renamed Saveable.saves to saves_for
Renamed Saveable.saved to save_by,
Removed Saveable.save_by alias (was an alias for :save_up)
Renamed Saveable.unsave_for to unsave_by
Renamed Saveable.find_saves to find_saves_for
Renamed Saveable.up_saves to get_upsaves
- and its aliases :get_true_saves, :get_ups, :get_upsaves, :get_for_saves
Renamed Saveable.down_saves to get_downsaves
- and its aliases :get_false_saves, :get_downs, :get_downsaves

License

Acts as saveable is released under the MIT License.

TODO

Pass in a block of options when creating acts_as. Allow for things like disabling the aliasing
The aliased methods are referred to by using the terms 'up/down' and/or 'true/false'. Need to come up with guidelines for naming these methods.
Create more aliases. Specifically for counting saves and finding saves.

acts_as_saveable

Development