# SmartAttr

This gem helps you make your model's attribute smart.You can get many useful methods with only a little code.

## Installation

Add this line to your application's Gemfile:

```ruby
gem 'smart_attr'
```

And then execute:

    $ bundle

Or install it yourself as:

    $ gem install smart_attr

## Usage

### Basic Usage(Without database)

'Without database' means that your model does not inherit from something like ActiveRecord::Base, and does not include something like Mongoid::Document.

You can see more details in the example below:

```ruby
class Movie

  include SmartAttr::Base

  smart_attr :star, config: {
    one:    { value: 1, desc: 'one star' },
    two:    { value: 2, desc: 'two star' },
    three:  { value: 3, desc: 'three star' },
    four:   { value: 4, desc: 'four star' },
    five:   { value: 5, desc: 'five star' }
  }
end

Movie.star_config_hash
# => { :one=>{:value=>1, :desc=>"one star"},
#      :two=>{:value=>2, :desc=>"two star"},
#      :three=>{:value=>3, :desc=>"three star"},
#      :four=>{:value=>4, :desc=>"four star"},
#      :five=>{:value=>5, :desc=>"five star"}
#    }

movie = Movie.new # => #<Movie:0x007fcc041b0490>

movie.star = 1  # => 1
movie.star_name # => :one
movie.star_desc # => "one star"
movie.star_one? # => true
movie.star_two? # => false

movie.star_two! # => 2
movie.star      # => 2
movie.star_two? # => true

movie.star_config # => {:value=>2, :desc=>"two star", :key=>:two}
```

In this situation, an instance_variable is created to store the value when you set value for the attribute.

For example:

```ruby
movie = Movie.new # => #<Movie:0x007fcc041b0490>
movie.star = 3 # =>3

# By run 'movie.inspect', you can see that there is an instance_variable named '@star'.
movie.inspect # => "#<Movie:0x007fcc041b0490 @star=3>"
```

### Used With ActiveRecord

It is almost the same like the basic usage when used with ActiveRecord.

The only difference is that it will not create an instance_variable to store the value when you set value for the attribute.
This is because it will store the value in the database. 

For example, suppose you have a class named "Movie" with database table 'movies', then you should ensure that 'movies' have column 'star' before you use 'smart_attr :star, config: { # something }'

```ruby
class Movie

  include SmartAttr::Base

  smart_attr :star, config: {
    one:    { value: 1, desc: 'one star' },
    two:    { value: 2, desc: 'two star' },
    three:  { value: 3, desc: 'three star' },
    four:   { value: 4, desc: 'four star' },
    five:   { value: 5, desc: 'five star' }
  }
end

Movie.star_config_hash
# => { :one=>{:value=>1, :desc=>"one star"},
#      :two=>{:value=>2, :desc=>"two star"},
#      :three=>{:value=>3, :desc=>"three star"},
#      :four=>{:value=>4, :desc=>"four star"},
#      :five=>{:value=>5, :desc=>"five star"}
#    }

movie = Movie.new # => #<Movie:0x007fcc041b0490>

movie.star = 1  # => 1
movie.star_name # => :one
movie.star_desc # => "one star"
movie.star_one? # => true
movie.star_two? # => false

movie.star_two! # => 2
movie.star      # => 2
movie.star_two? # => true

movie.star_config # => {:value=>2, :desc=>"two star", :key=>:two}
```

### Used With Mongoid

Same like used with ActiveRecord.


## Supported Ruby Version
From 2.0.0 To 2.3.3

NOTE: 2.4.0 is not supported yet!

## Status
[![Build Status](https://travis-ci.org/liukgg/smart_attr.png)](https://travis-ci.org/liukgg/smart_attr)

## TODO
- Introduce SimpleCov

## Development

After checking out the repo, run `bin/setup` to install dependencies. Then, run `rake spec` to run the tests. You can also run `bin/console` for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run `bundle exec rake install`. To release a new version, update the version number in `version.rb`, and then run `bundle exec rake release`, which will create a git tag for the version, push git commits and tags, and push the `.gem` file to [rubygems.org](https://rubygems.org).

## Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/liukgg/smart_attr. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the [Contributor Covenant](http://contributor-covenant.org) code of conduct.


## License

The gem is available as open source under the terms of the [MIT License](http://opensource.org/licenses/MIT).