Merge pull request #119 from godfat/sequel

Add sequel support.

README.md

@@ -278,6 +278,23 @@ class Job < ActiveRecord::Base
 end
 ```
 
+### Sequel
+
+AASM also supports Sequel besides ActiveRecord.
+
+```ruby
+class Job < Sequel::Model
+  include AASM
+
+  aasm do # default column: aasm_state
+    ...
+  end
+end
+```
+
+However it's not yet feature completed as ActiveRecord. For example,
+no scope would be defined as in ActiveRecord. See _Automatic Scopes_.
+
 ### Mongoid
 
 AASM also supports persistence to Mongodb if you're using Mongoid. Make sure

lib/aasm/persistence.rb

@@ -12,6 +12,9 @@ module AASM
         elsif hierarchy.include?("Mongoid::Document")
           require_files_for(:mongoid)
           base.send(:include, AASM::Persistence::MongoidPersistence)
+        elsif hierarchy.include?("Sequel::Model")
+          require_files_for(:sequel)
+          base.send(:include, AASM::Persistence::SequelPersistence)
         end
       end
 

lib/aasm/persistence/sequel_persistence.rb

@@ -0,0 +1,108 @@
+module AASM
+  module Persistence
+    module SequelPersistence
+      def self.included(base)
+        base.send(:include, AASM::Persistence::Base)
+        base.send(:include, AASM::Persistence::SequelPersistence::InstanceMethods)
+      end
+
+      module InstanceMethods
+        def before_validation
+          aasm_ensure_initial_state
+          super
+        end
+
+        def before_create
+          aasm_ensure_initial_state
+          super
+        end
+
+        # Returns the value of the aasm_column - called from <tt>aasm.current_state</tt>
+        #
+        # If it's a new record, and the aasm state column is blank it returns the initial state
+        #
+        #   class Foo < Sequel::Model
+        #     include AASM
+        #     aasm :column => :status do
+        #       state :opened
+        #       state :closed
+        #     end
+        #   end
+        #
+        #   foo = Foo.new
+        #   foo.current_state # => :opened
+        #   foo.close
+        #   foo.current_state # => :closed
+        #
+        #   foo = Foo[1]
+        #   foo.current_state # => :opened
+        #   foo.aasm_state = nil
+        #   foo.current_state # => nil
+        #
+        # NOTE: intended to be called from an event
+        #
+        # This allows for nil aasm states - be sure to add validation to your model
+        def aasm_read_state
+          state = send(self.class.aasm_column)
+          if new? && state.to_s.strip.empty?
+            aasm.determine_state_name(self.class.aasm.initial_state)
+          elsif state.nil?
+            nil
+          else
+            state.to_sym
+          end
+        end
+
+        # 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.enter_initial_state if
+            send(self.class.aasm_column).to_s.strip.empty?
+        end
+
+        # Writes <tt>state</tt> to the state column and persists it to the database
+        #
+        #   foo = Foo[1]
+        #   foo.aasm.current_state # => :opened
+        #   foo.close!
+        #   foo.aasm.current_state # => :closed
+        #   Foo[1].aasm.current_state # => :closed
+        #
+        # NOTE: intended to be called from an event
+        def aasm_write_state state
+          aasm_column = self.class.aasm_column
+          update_ony({aasm_column => state.to_s}, aasm_column)
+        end
+
+        # Writes <tt>state</tt> to the state column, but does not persist it to the database
+        #
+        #   foo = Foo[1]
+        #   foo.aasm.current_state # => :opened
+        #   foo.close
+        #   foo.aasm.current_state # => :closed
+        #   Foo[1].aasm.current_state # => :opened
+        #   foo.save
+        #   foo.aasm.current_state # => :closed
+        #   Foo[1].aasm.current_state # => :closed
+        #
+        # NOTE: intended to be called from an event
+        def aasm_write_state_without_persistence state
+          send("#{self.class.aasm_column}=", state.to_s)
+        end
+      end
+    end
+  end
+end

spec/unit/persistence/sequel_persistence_spec.rb

@@ -0,0 +1,103 @@
+
+describe 'sequel' do
+  begin
+    require 'sequel'
+    require 'logger'
+    require 'spec_helper'
+
+    before(:all) do
+      db = Sequel.sqlite
+      # if you want to see the statements while running the spec enable the following line
+      # db.loggers << Logger.new($stderr)
+      db.create_table(:models) do
+        primary_key :id
+        String :status
+      end
+
+      @model = Class.new(Sequel::Model(db)) do
+        set_dataset(:models)
+        attr_accessor :default
+        include AASM
+        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
+    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 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
+        allow(model).to receive(:new?).and_return(false)
+        model.status = "gamma"
+        expect(model.aasm.current_state).to eq(:gamma)
+      end
+
+      it "should allow a nil state" do
+        allow(model).to receive(:new?).and_return(false)
+        model.status = nil
+        expect(model.aasm.current_state).to be_nil
+      end
+
+      it "should call aasm_ensure_initial_state on validation before create" do
+        expect(model).to receive(:aasm_ensure_initial_state).and_return(true)
+        model.valid?
+      end
+
+      it "should call aasm_ensure_initial_state before create, even if skipping validations" do
+        expect(model).to receive(:aasm_ensure_initial_state).and_return(true)
+        model.save(:validate => false)
+      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_column).to eq(:status)
+        expect(Class.new(@model).aasm_column).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 "Not running Sequel specs because sequel gem if not installed!!!"
+  end
+end