= active_finite

== What is active_finite?

The goal of active_finite is to provide a simple way to define
database enumerations with ActiveRecord. There are many[https://github.com/ikspres/enum_fu] existing[https://github.com/adzap/active_enum] projects[https://github.com/jeffp/enumerated_attribute] that bring some enum support to ActiveRecord. However, these projects tend to define the enums in code, instead of in the migration itself. 

== Hello, active_finite!

Let's start by defining a simple migration:

  require 'active_finite'
  require 'active_record'
  require 'active_support/core_ext'

  class Hellos < ActiveRecord::Migration
    self.up
      create_table :hellos do |t|
        t.string default_column_name, :null => false
      end
      create_finite in_table: :hellos, values: ['oy', 'que tal', 'hi']
    end

    self.down
      drop_finite in_table: :hellos, values: ['oy', 'que tal', 'hi']
      drop_table :hellos
    end
  end

Note that if it doesn't matter what the column's name is, the method 
default_column_name can be used.

Now that we some hellos in our Hello model, we can access them using:
hellos = active_finite :hellos

The variable hellos now holds a class derived from ActiveRecord named 
Hello, so all of the normal ActiveRecord methods can be used.
By using the method active_finite, there is no need to define the model classes
explicitly.

== Other options
If the column name must be different than the default (i.e. when working with
an existing database), the column_name option can be used. Also, a json
file can be used instead of explicitly listing the possible values in 
the migration. For example:

  require 'active_finite'
  require 'active_record'
  require 'active_support/core_ext'
  class HellosWithCustomColumn < ActiveRecord::Migration
    self.up
      create_table :hellos do |t|
        t.string :custom, :null => false
      end
      create_finite in_table: :hellos,
                    values: ['oy', 'que tal', 'hi']
                    column_name: :custom
                    from_file: 'hellos.json'
    end

    self.down
      drop_finite in_table: :hellos, values: ['oy', 'que tal', 'hi']
      drop_table :hellos
    end
  end

If both values and from_file are defined, active_finite will pull entries from both.

== Other ideas
Combine active_finite with foreigner[https://github.com/matthuhiggins/foreigner] to put foreign key constraints on users of defined enums.

== Contributing to active_finite
* Check out the latest master to make sure the feature hasn't been implemented or the bug hasn't been fixed yet
* Check out the issue tracker to make sure someone already hasn't requested it and/or contributed it
* Fork the project
* Start a feature/bugfix branch
* Commit and push until you are happy with your contribution
* Make sure to add tests for it. This is important so I don't break it in a future version unintentionally.
* Please try not to mess with the Rakefile, version, or history. If you want to have your own version, or is otherwise necessary, that is fine, but please isolate to its own commit so I can cherry-pick around it.

== Contact
me@stuffivemade.com

== Copyright

Copyright (c) 2011 me. See LICENSE.txt for
further details.