Add [dynamoid](http://github.com/Veraticus/Dynamoid) support.

.travis.yml

@@ -26,6 +26,11 @@ gemfile:
   - gemfiles/rails_4.2_mongoid_5.gemfile
   - gemfiles/rails_4.2_mongo_mapper.gemfile
 
+before_script:
+  - mkdir /tmp/dynamodb
+  - wget -O - http://dynamodb-local.s3-website-us-west-2.amazonaws.com/dynamodb_local_latest | tar xz --directory /tmp/dynamodb
+  - java -Djava.library.path=/tmp/dynamodb/DynamoDBLocal_lib -jar /tmp/dynamodb/DynamoDBLocal.jar -inMemory -delayTransientStatuses -port 30180 &
+
 matrix:
   allow_failures:
     - rvm: rbx-2.2.1

Gemfile

@@ -7,6 +7,8 @@ gem "activerecord-jdbcsqlite3-adapter", :platforms => :jruby
 gem "rails", "~>4.2"
 gem 'mongoid', '~>4.0' if Gem::Version.create(RUBY_VERSION.dup) >= Gem::Version.create('1.9.3')
 gem 'sequel'
+gem 'dynamoid', '~> 1'
+gem 'aws-sdk', '~>2'
 # Since mongoid V4 requires incompatible bson V2, cannot have mongoid (V4 or greater)
 # and mongo_mapper ( or mongo ) in the same application
 # gem 'mongo_mapper', '~> 0.13'

gemfiles/rails_4.0.gemfile

@@ -8,5 +8,7 @@ gem "activerecord-jdbcsqlite3-adapter", :platforms => :jruby
 gem "rails", "4.0.13"
 gem 'mongoid', '~>4.0' if Gem::Version.create(RUBY_VERSION.dup) >= Gem::Version.create('1.9.3')
 gem 'sequel'
+gem 'dynamoid', '~> 1',                 :platforms => :ruby
+gem 'aws-sdk', '~>2',                   :platforms => :ruby
 
 gemspec :path => "../"

gemfiles/rails_4.0_mongo_mapper.gemfile

@@ -10,5 +10,7 @@ gem "rails", "4.0.13"
 gem 'sequel'
 gem 'mongo_mapper', '~>0.13'
 gem 'bson_ext',                          :platforms => :ruby
+gem 'dynamoid', '~> 1',                  :platforms => :ruby
+gem 'aws-sdk', '~>2',                    :platforms => :ruby
 
 gemspec :path => "../"

gemfiles/rails_4.1.gemfile

@@ -8,5 +8,7 @@ gem "activerecord-jdbcsqlite3-adapter", :platforms => :jruby
 gem "rails", "4.1.9"
 gem 'mongoid', '~>4.0' if Gem::Version.create(RUBY_VERSION.dup) >= Gem::Version.create('1.9.3')
 gem 'sequel'
+gem 'dynamoid', '~> 1',                 :platforms => :ruby
+gem 'aws-sdk', '~>2',                   :platforms => :ruby
 
 gemspec :path => "../"

gemfiles/rails_4.1_mongo_mapper.gemfile

@@ -10,5 +10,7 @@ gem "rails", "4.1.9"
 gem 'sequel'
 gem 'mongo_mapper', '~> 0.13'
 gem 'bson_ext',                          :platforms => :ruby
+gem 'dynamoid', '~> 1',                  :platforms => :ruby
+gem 'aws-sdk', '~>2',                    :platforms => :ruby
 
 gemspec :path => "../"

gemfiles/rails_4.2.gemfile

@@ -8,5 +8,7 @@ gem "activerecord-jdbcsqlite3-adapter", :platforms => :jruby
 gem "rails", "4.2.0"
 gem 'mongoid', '~>4.0' if Gem::Version.create(RUBY_VERSION.dup) >= Gem::Version.create('1.9.3')
 gem 'sequel'
+gem 'dynamoid', '~> 1',                 :platforms => :ruby
+gem 'aws-sdk', '~>2',                   :platforms => :ruby
 
 gemspec :path => "../"

gemfiles/rails_4.2_mongo_mapper.gemfile

@@ -10,5 +10,7 @@ gem "rails", "4.2.0"
 gem 'sequel'
 gem 'mongo_mapper'
 gem 'bson_ext',                          :platforms => :ruby
+gem 'dynamoid', '~> 1',                  :platforms => :ruby
+gem 'aws-sdk', '~>2',                    :platforms => :ruby
 
 gemspec :path => "../"

gemfiles/rails_4.2_mongoid_5.gemfile

@@ -8,5 +8,7 @@ gem "activerecord-jdbcsqlite3-adapter", :platforms => :jruby
 gem "rails", "4.2.0"
 gem 'mongoid', '~>5.0' if Gem::Version.create(RUBY_VERSION.dup) >= Gem::Version.create('1.9.3')
 gem 'sequel'
+gem 'dynamoid', '~> 1',                 :platforms => :ruby
+gem 'aws-sdk', '~>2',                   :platforms => :ruby
 
 gemspec :path => "../"

lib/aasm/persistence.rb

@@ -14,6 +14,8 @@ module AASM
           include_persistence base, :mongo_mapper
         elsif hierarchy.include?("Sequel::Model")
           include_persistence base, :sequel
+        elsif hierarchy.include?("Dynamoid::Document")
+          include_persistence base, :dynamoid
         else
           include_persistence base, :plain
         end

lib/aasm/persistence/dynamoid_persistence.rb

@@ -0,0 +1,94 @@
+require_relative 'base'
+
+module AASM
+  module Persistence
+    module DynamoidPersistence
+      def self.included(base)
+        base.send(:include, AASM::Persistence::Base)
+        base.send(:include, AASM::Persistence::DynamoidPersistence::InstanceMethods)
+
+        base.after_initialize :aasm_ensure_initial_state
+
+        # Because Dynamoid only use define_method to add attribute assignment method in Class.
+        #
+        # In AASM::Base.initialize, it redefines and calls super in this method without superclass method.
+        # We override method_missing to solve this problem.
+        #
+        base.class_eval %Q(
+          def method_missing(method_name, *arguments, &block)
+            if (AASM::StateMachine[self.class].keys.map { |state_machine_name| self.class.aasm(state_machine_name).attribute_name.to_s + "=" }).include? method_name.to_s
+              attribute_name = method_name.to_s.gsub("=", '')
+              write_attribute(attribute_name.to_sym, *arguments)
+            else
+              super
+            end
+          end
+        )
+      end
+
+      module InstanceMethods
+
+        # Writes <tt>state</tt> to the state column and persists it to the database
+        # using update_attribute (which bypasses validation)
+        #
+        #   foo = Foo.find(1)
+        #   foo.aasm.current_state # => :opened
+        #   foo.close!
+        #   foo.aasm.current_state # => :closed
+        #   Foo.find(1).aasm.current_state # => :closed
+        #
+        # NOTE: intended to be called from an event
+        def aasm_write_state(state, name=:default)
+          old_value = read_attribute(self.class.aasm(name).attribute_name)
+          write_attribute(self.class.aasm(name).attribute_name, state.to_s)
+
+          unless self.save(:validate => false)
+            write_attribute(self.class.aasm(name).attribute_name, old_value)
+            return false
+          end
+
+          true
+        end
+
+        # Writes <tt>state</tt> to the state column, but does not persist it to the database
+        #
+        #   foo = Foo.find(1)
+        #   foo.aasm.current_state # => :opened
+        #   foo.close
+        #   foo.aasm.current_state # => :closed
+        #   Foo.find(1).aasm.current_state # => :opened
+        #   foo.save
+        #   foo.aasm.current_state # => :closed
+        #   Foo.find(1).aasm.current_state # => :closed
+        #
+        # NOTE: intended to be called from an event
+        def aasm_write_state_without_persistence(state, name=:default)
+          write_attribute(self.class.aasm(name).attribute_name, state.to_s)
+        end
+
+      private
+
+        # Ensures that if the aasm_state column is nil and the record is new
+        # that the initial state gets populated before validation on create
+        #
+        #   foo = Foo.new
+        #   foo.aasm_state # => nil
+        #   foo.valid?
+        #   foo.aasm_state # => "open" (where :open is the initial state)
+        #
+        #
+        #   foo = Foo.find(:first)
+        #   foo.aasm_state # => 1
+        #   foo.aasm_state = nil
+        #   foo.valid?
+        #   foo.aasm_state # => nil
+        #
+        def aasm_ensure_initial_state
+          AASM::StateMachine[self.class].keys.each do |state_machine_name|
+            aasm(state_machine_name).enter_initial_state if send(self.class.aasm(state_machine_name).attribute_name).blank?
+          end
+        end
+      end # InstanceMethods
+    end
+  end # Persistence
+end # AASM

spec/models/dynamoid/complex_dynamoid_example.rb

@@ -0,0 +1,37 @@
+class ComplexDynamoidExample
+  include Dynamoid::Document
+  include AASM
+
+  field :left
+  field :right
+
+  aasm :left, :column => 'left' do
+    state :one, :initial => true
+    state :two
+    state :three
+
+    event :increment do
+      transitions :from => :one, :to => :two
+      transitions :from => :two, :to => :three
+    end
+    event :reset do
+      transitions :from => :three, :to => :one
+    end
+  end
+
+  aasm :right, :column => 'right' do
+    state :alpha, :initial => true
+    state :beta
+    state :gamma
+
+    event :level_up do
+      transitions :from => :alpha, :to => :beta
+      transitions :from => :beta, :to => :gamma
+    end
+    event :level_down do
+      transitions :from => :gamma, :to => :beta
+      transitions :from => :beta, :to => :alpha
+    end
+  end
+
+end

spec/models/dynamoid/dynamoid_multiple.rb

@@ -0,0 +1,18 @@
+class DynamoidMultiple
+  include Dynamoid::Document
+  include AASM
+
+  field :status
+
+  attr_accessor :default
+
+  aasm :left, :column => :status
+  aasm :left do
+    state :alpha, :initial => true
+    state :beta
+    state :gamma
+    event :release do
+      transitions :from => [:alpha, :beta, :gamma], :to => :beta
+    end
+  end
+end

spec/models/dynamoid/dynamoid_simple.rb

@@ -0,0 +1,18 @@
+class DynamoidSimple
+  include Dynamoid::Document
+  include AASM
+
+  field :status
+
+  attr_accessor :default
+
+  aasm :column => :status
+  aasm do
+    state :alpha, :initial => true
+    state :beta
+    state :gamma
+    event :release do
+      transitions :from => [:alpha, :beta, :gamma], :to => :beta
+    end
+  end
+end

spec/spec_helper.rb

@@ -18,6 +18,39 @@ def load_schema
   require File.dirname(__FILE__) + "/database.rb"
 end
 
+# Dynamoid initialization
+begin
+  require 'dynamoid'
+  require 'aws-sdk-resources'
+
+  ENV['ACCESS_KEY'] ||= 'abcd'
+  ENV['SECRET_KEY'] ||= '1234'
+
+  Aws.config.update({
+    region: 'us-west-2',
+    credentials: Aws::Credentials.new(ENV['ACCESS_KEY'], ENV['SECRET_KEY'])
+  })
+
+  Dynamoid.configure do |config|
+    config.namespace = "dynamoid_tests"
+    config.endpoint = 'http://127.0.0.1:30180'
+    config.warn_on_scan = false
+  end
+
+  Dynamoid.logger.level = Logger::FATAL
+
+  RSpec.configure do |c|
+    c.before(:each) do
+      Dynamoid.adapter.list_tables.each do |table|
+        Dynamoid.adapter.delete_table(table) if table =~ /^#{Dynamoid::Config.namespace}/
+      end
+      Dynamoid.adapter.tables.clear
+    end
+  end
+rescue LoadError
+  # Without Dynamoid settings
+end
+
 # custom spec helpers
 Dir[File.dirname(__FILE__) + "/spec_helpers/**/*.rb"].sort.each { |f| require File.expand_path(f) }
 

spec/unit/persistence/dynamoid_persistence_multiple_spec.rb

@@ -0,0 +1,140 @@
+describe 'dynamoid' do
+  begin
+    require 'dynamoid'
+    require 'logger'
+    require 'spec_helper'
+
+    Dir[File.dirname(__FILE__) + "/../../models/dynamoid/*.rb"].sort.each do |f|
+      require File.expand_path(f)
+    end
+
+    before(:all) do
+      @model = DynamoidMultiple
+    end
+
+    describe "instance methods" do
+      let(:model) {@model.new}
+
+      it "should respond to aasm persistence methods" do
+        expect(model).to respond_to(:aasm_read_state)
+        expect(model).to respond_to(:aasm_write_state)
+        expect(model).to respond_to(:aasm_write_state_without_persistence)
+      end
+
+      it "should return the initial state when new and the aasm field is nil" do
+        expect(model.aasm(:left).current_state).to eq(:alpha)
+      end
+
+      it "should save the initial state" do
+        model.save
+        expect(model.status).to eq("alpha")
+      end
+
+      it "should return the aasm column when new and the aasm field is not nil" do
+        model.status = "beta"
+        expect(model.aasm(:left).current_state).to eq(:beta)
+      end
+
+      it "should return the aasm column when not new and the aasm_column is not nil" do
+        model.save
+        model.status = "gamma"
+        expect(model.aasm(:left).current_state).to eq(:gamma)
+      end
+
+      it "should allow a nil state" do
+        model.save
+        model.status = nil
+        expect(model.aasm(:left).current_state).to be_nil
+      end
+
+      it "should not change the state if state is not loaded" do
+        model.release
+        model.save
+        model.reload
+        expect(model.aasm(:left).current_state).to eq(:beta)
+      end
+    end
+
+    describe 'subclasses' do
+      it "should have the same states as its parent class" do
+        expect(Class.new(@model).aasm(:left).states).to eq(@model.aasm(:left).states)
+      end
+
+      it "should have the same events as its parent class" do
+        expect(Class.new(@model).aasm(:left).events).to eq(@model.aasm(:left).events)
+      end
+
+      it "should have the same column as its parent even for the new dsl" do
+        expect(@model.aasm(:left).attribute_name).to eq(:status)
+        expect(Class.new(@model).aasm(:left).attribute_name).to eq(:status)
+      end
+    end
+
+    describe 'initial states' do
+      it 'should support conditions' do
+        @model.aasm(:left) do
+          initial_state lambda{ |m| m.default }
+        end
+
+        expect(@model.new(:default => :beta).aasm(:left).current_state).to eq(:beta)
+        expect(@model.new(:default => :gamma).aasm(:left).current_state).to eq(:gamma)
+      end
+    end
+
+    describe "complex example" do
+      it "works" do
+        record = ComplexDynamoidExample.new
+        expect(record.aasm(:left).current_state).to eql :one
+        expect(record.aasm(:right).current_state).to eql :alpha
+
+        record.save
+        expect_aasm_states record, :one, :alpha
+        record.reload
+        expect_aasm_states record, :one, :alpha
+
+        record.increment!
+        expect_aasm_states record, :two, :alpha
+        record.reload
+        expect_aasm_states record, :two, :alpha
+
+        record.level_up!
+        expect_aasm_states record, :two, :beta
+        record.reload
+        expect_aasm_states record, :two, :beta
+
+        record.increment!
+        expect { record.increment! }.to raise_error(AASM::InvalidTransition)
+        expect_aasm_states record, :three, :beta
+        record.reload
+        expect_aasm_states record, :three, :beta
+
+        record.level_up!
+        expect_aasm_states record, :three, :gamma
+        record.reload
+        expect_aasm_states record, :three, :gamma
+
+        record.level_down # without saving
+        expect_aasm_states record, :three, :beta
+        record.reload
+        expect_aasm_states record, :three, :gamma
+
+        record.level_down # without saving
+        expect_aasm_states record, :three, :beta
+        record.reset!
+        expect_aasm_states record, :one, :beta
+      end
+
+      def expect_aasm_states(record, left_state, right_state)
+        expect(record.aasm(:left).current_state).to eql left_state.to_sym
+        expect(record.left).to eql left_state.to_s
+        expect(record.aasm(:right).current_state).to eql right_state.to_sym
+        expect(record.right).to eql right_state.to_s
+      end
+    end
+
+  rescue LoadError
+    puts "------------------------------------------------------------------------"
+    puts "Not running Dynamoid multiple-specs because dynamoid gem is not installed!!!"
+    puts "------------------------------------------------------------------------"
+  end
+end

spec/unit/persistence/dynamoid_persistence_spec.rb

@@ -0,0 +1,89 @@
+describe 'dynamoid' do
+  begin
+    require 'dynamoid'
+    require 'logger'
+    require 'spec_helper'
+
+    Dir[File.dirname(__FILE__) + "/../../models/dynamoid/*.rb"].sort.each do |f|
+      require File.expand_path(f)
+    end
+
+    before(:all) do
+      @model = DynamoidSimple
+    end
+
+    describe "instance methods" do
+      let(:model) {@model.new}
+
+      it "should respond to aasm persistence methods" do
+        expect(model).to respond_to(:aasm_read_state)
+        expect(model).to respond_to(:aasm_write_state)
+        expect(model).to respond_to(:aasm_write_state_without_persistence)
+      end
+
+      it "should return the initial state when new and the aasm field is nil" do
+        expect(model.aasm.current_state).to eq(:alpha)
+      end
+
+      it "should save the initial state" do
+        model.save
+        expect(model.status).to eq("alpha")
+      end
+
+      it "should return the aasm column when new and the aasm field is not nil" do
+        model.status = "beta"
+        expect(model.aasm.current_state).to eq(:beta)
+      end
+
+      it "should return the aasm column when not new and the aasm_column is not nil" do
+        model.save
+        model.status = "gamma"
+        expect(model.aasm.current_state).to eq(:gamma)
+      end
+
+      it "should allow a nil state" do
+        model.save
+        model.status = nil
+        expect(model.aasm.current_state).to be_nil
+      end
+
+      it "should not change the state if state is not loaded" do
+        model.release
+        model.save
+        model.reload
+        expect(model.aasm.current_state).to eq(:beta)
+      end
+    end
+
+    describe 'subclasses' do
+      it "should have the same states as its parent class" do
+        expect(Class.new(@model).aasm.states).to eq(@model.aasm.states)
+      end
+
+      it "should have the same events as its parent class" do
+        expect(Class.new(@model).aasm.events).to eq(@model.aasm.events)
+      end
+
+      it "should have the same column as its parent even for the new dsl" do
+        expect(@model.aasm.attribute_name).to eq(:status)
+        expect(Class.new(@model).aasm.attribute_name).to eq(:status)
+      end
+    end
+
+    describe 'initial states' do
+      it 'should support conditions' do
+        @model.aasm do
+          initial_state lambda{ |m| m.default }
+        end
+
+        expect(@model.new(:default => :beta).aasm.current_state).to eq(:beta)
+        expect(@model.new(:default => :gamma).aasm.current_state).to eq(:gamma)
+      end
+    end
+
+  rescue LoadError
+    puts "------------------------------------------------------------------------"
+    puts "Not running Dynamoid specs because dynamoid gem is not installed!!!"
+    puts "------------------------------------------------------------------------"
+  end
+end