Runnable minimapper example (you just need some version of ruby installed)

0_how_to_run.sh

# Copy and paste this into a terminal:
gem install minimapper
gem install activemodel # required for Minimapper::Entity[::Rails] (you can use Minimapper::Entity::Core without it)
curl https://gist.github.com/joakimk/3904952/raw/56b592e6eaa5a0206bf9207b0ee53aa0114a53eb/minimapper_example.rb > minimapper_example.rb
ruby minimapper_example.rb

minimapper_example.rb

# minimapper_example.rb
require "rubygems"
require "minimapper"
require "minimapper/entity"
require "minimapper/mapper/memory"

class User
  include Minimapper::Entity

  attributes :name, :email
  validates :name, :presence => true
end

class UserMapper < Minimapper::Mapper::Memory
end

## Creating
user = User.new(:name => "Joe")
user_mapper = UserMapper.new
user_mapper.create(user)

## Finding
user = user_mapper.find(user.id)
p user.name              # => Joe
p user_mapper.first.name # => Joe

## Updating
user.name = "Joey"
user_mapper.update(user)
p user_mapper.first.name # => Joey

## Deleting
old_id = user.id
user_mapper.delete(user)
p user.id                        # => nil
p user_mapper.find_by_id(old_id) # => nil
# user_mapper.find(old_id)       # raises Minimapper::Common::CanNotFindEntity
# user_mapper.delete_all
# user_mapper.delete_by_id(1)

## Using a repository
require "minimapper/repository"

repository = Minimapper::Repository.build({
  :users    => UserMapper.new
  # :projects => ProjectMapper.new
})

user = User.new(:name => "Joe")
repository.users.create(user)
p repository.users.find(user.id).name # => Joe
repository.users.delete_all

## Using ActiveModel validations
user = User.new
repository.users.create(user)
p repository.users.count    # => 0
p user.errors.full_messages # Name can't be blank