Add transaction_with for transaction multiple models related

lib/switch_point/model.rb

@@ -47,11 +47,36 @@ def switch_point_proxy
         end
       end
 
+      def transaction_with(*models, &block)
+        unless can_transaction_with?(*models)
+          raise RuntimeError.new("switch_point's model names must be consistent")
+        end
+
+        with_writable do
+          self.transaction(&block)
+        end
+      end
+
       private
 
       def assert_existing_switch_point!(name)
         SwitchPoint.config.fetch(name)
       end
+
+      def can_transaction_with?(*models)
+        writable_switch_points = [self, *models].map do |model|
+          if model.instance_variable_defined?(:@switch_point_name)
+            SwitchPoint.config.model_name(
+              model.instance_variable_get(:@switch_point_name),
+              :writable
+            )
+          else
+            nil
+          end
+        end
+
+        writable_switch_points.uniq.size == 1
+      end
     end
   end
 end

spec/models.rb

@@ -2,6 +2,9 @@
   config.define_switch_point :main,
     readonly: :main_readonly,
     writable: :main_writable
+  config.define_switch_point :main2,
+    readonly: :main2_readonly,
+    writable: :main2_writable
   config.define_switch_point :user,
     readonly: :user,
     writable: :user
@@ -31,6 +34,14 @@ def do_after_save
   end
 end
 
+class Book2 < ActiveRecord::Base
+  use_switch_point :main
+end
+
+class Book3 < ActiveRecord::Base
+  use_switch_point :main2
+end
+
 class Publisher < ActiveRecord::Base
   use_switch_point :main
 end
@@ -66,6 +77,8 @@ class Nanika3 < ActiveRecord::Base
 ActiveRecord::Base.configurations = {
   'main_readonly' => base.merge(database: 'main_readonly.sqlite3'),
   'main_writable' => base.merge(database: 'main_writable.sqlite3'),
+  'main2_readonly' => base.merge(database: 'main2_readonly.sqlite3'),
+  'main2_writable' => base.merge(database: 'main2_writable.sqlite3'),
   'main_readonly_special' => base.merge(database: 'main_readonly_special.sqlite3'),
   'user' => base.merge(database: 'user.sqlite3'),
   'comment_readonly' => base.merge(database: 'comment_readonly.sqlite3'),

spec/spec_helper.rb

@@ -38,8 +38,19 @@
     Book.with_writable do
       Book.connection.execute('CREATE TABLE books (id integer primary key autoincrement)')
     end
+
+    Book2.with_writable do
+      Book2.connection.execute('CREATE TABLE book2s (id integer primary key autoincrement)')
+    end
+
     FileUtils.cp('main_writable.sqlite3', 'main_readonly.sqlite3')
 
+    Book3.with_writable do
+      Book3.connection.execute('CREATE TABLE book3s (id integer primary key autoincrement)')
+    end
+
+    FileUtils.cp('main2_writable.sqlite3', 'main2_readonly.sqlite3')
+
     Note.connection.execute('CREATE TABLE notes (id integer primary key autoincrement)')
 
     Nanika3.connection.execute('CREATE TABLE nanika3s (id integer primary key)')

spec/switch_point/model_spec.rb

@@ -261,4 +261,112 @@
       end
     end
   end
+
+  describe '.transaction_with' do
+    context "when each model has a same writable" do
+      before do
+        @before_book_count  = Book.count
+        @before_book2_count = Book2.count
+
+        Book.transaction_with(Book2) do
+          new_book  = Book.create
+          new_book2 = Book2.create
+        end
+
+        @after_book_count = Book.with_writable do
+          Book.count
+        end
+        @after_book2_count = Book2.with_writable do
+          Book2.count
+        end
+      end
+
+      it 'should create a new record' do
+        expect(
+          Book.with_writable do
+            Book.count
+          end
+        ).to be > @before_book_count
+
+        expect(
+          Book2.with_writable do
+            Book2.count
+          end
+        ).to be > @before_book2_count
+      end
+    end
+
+    context "when each model has a other writable" do
+      it {
+        expect {
+          Book.transaction_with(Book3) do
+            new_book  = Book.create
+            new_book3 = Book3.create
+          end
+        }.to raise_error RuntimeError
+      }
+    end
+
+    context "when raise exception in transaction that include some model, and models each have other writable" do
+      before do
+        @before_book_count  = Book.count
+        @before_book3_count = Book3.count
+
+        Book.transaction_with(Book2) do
+          new_book  = Book.create
+          new_book3 = Book3.with_writable do
+            Book3.create
+          end
+          raise ActiveRecord::Rollback
+        end
+      end
+
+      it 'Book should not create a new record (rollbacked)' do
+        expect(
+          Book.with_writable do
+            Book.count
+          end
+        ).to eq @before_book_count
+      end
+
+      it 'Book3 should create a new record (not rollbacked)' do
+        expect(
+          Book3.with_writable do
+            Book3.count
+          end
+        ).to be > @before_book3_count
+      end
+    end
+
+    context "when nested transaction_with then parent transaction rollbacked" do
+      before do
+        @before_book_count  = Book.count
+        @before_book3_count = Book3.count
+
+        Book.transaction_with do
+          Book.create
+
+          Book3.transaction_with do
+            Book3.create
+          end
+
+          raise ActiveRecord::Rollback
+        end
+
+        it {
+          expect(
+            Book.with_writable do
+              Book.count
+            end
+          ).to be = @before_book_count
+
+          expect(
+            Book3.with_writable do
+              Book3.count
+            end
+          ).to be > @before_book3_count
+        }
+      end
+    end
+  end
 end