app/models/raises_post.rb db/migrate/001_create_raises_posts.rb test/fixtures/raises_posts.yml test/unit/raises_post_test.rb @@ -1,4 +1,7 @@ +May 26 += finished first rough implementation + May 25 = add the needed parts of the Rails framework to run tests = README: the raison d'être \ No newline at end of file CHANGELOG @@ -1,19 +1,19 @@ = save_or_raise This plugin includes one new method for ActiveRecord::Base called - save_or_raise which does pretty much the same thing as + save_or_raise which does almost the same thing as ActiveRecord::Base#save! - == save() vs save!() + == save vs save! - The ActiveRecord::Base save() method returns true if the model save - is successful and false if it is not successful. The save!() method + The ActiveRecord::Base save method returns true if the model save + is successful and false if it is not successful. The save! method returns true if the model save is successful and raises an exception if it is not successful. == utility - The save() method is useful for control flow in cases where a failed + The save method is useful for control flow in cases where a failed save can be handled gracefully: if model.save @@ -22,22 +22,23 @@ ... end - Sometimes the control flow - often in or called by a controller - + Sometimes the control flow - often within or called by a controller - cannot handle an unsuccessful save gracefully. The programmer's choices are: - 1. Do not branch on the save() call and ignore failures. + 1. Do not branch on the save call and ignore failures. 2. Throw an exception: - raise "Save failed!" unless model.save + raise "Save failed!" unless model.save - 3. Call save!() which does the same as 2 + 3. Call save! which does the same as 2 The exception thrown by 2 and 3 will generate a 500 HTTP code for the user in production but it will also notify an admin by email when used in combination - with a plugin like exception_notification. The alternative situation generated - by 1 is possible data corruption and invalid application state. Doing 1 is just - not a good idea. + with a plugin like exception_notification. Result of choice 1 is possible data + corruption and invalid application state. + + So doing 1 is just not a good idea! == The problem with save! @@ -52,9 +53,12 @@ => "hello" >> a => "hello" + + The method strip! returns the result to b but also changes a. - The save! method does not change the ActiveRecord model it is called on. Also - the name save! does not hint that it throws an exception in the failure case. + The save! method does not change the ActiveRecord model it is called on any more + than the save method does. Also the name save! does not hint that it throws an + exception in the failure case. Both of these things make the code that uses save! less readable. @@ -62,15 +66,16 @@ This plugin implements a new ActiveRecord#Base method - save_or_raise(raiseable=RecordNotSaved) + save_or_raise(raiseable = ActiveRecord::RecordNotSaved) which can be used the following ways: model.save_or_raise # instead of model.save! - model.save_or_raise "Save failed!" - model.save_or_raise CustomException + model.save_or_raise "Save failed!" # raises RuntimeError with this message on failure + model.save_or_raise CustomException # raises CustomException on failure In all three cases the raised exception presents a 500 HTTP error to - the user in production. + the user in production if the save fails. - The save! method remains untouched and can still be used. \ No newline at end of file + The save! method remains untouched and can still be used. + \ No newline at end of file README @@ -1,2 +1 @@ -require 'save_or_raise' -ActiveRecord::Base.send(:include, ActiveRecord::SaveOrRaise) \ No newline at end of file +require 'save_or_raise' \ No newline at end of file init.rb @@ -1,13 +1,10 @@ -module ActiveRecord #:nodoc: +class ActiveRecord::Base - module SaveOrRaise #:nodoc: - - def save_or_raise(raiseable = RecordNotSaved) - success = save - raise raiseable unless success - success - end - + def save_or_raise(raiseable = ActiveRecord::RecordNotSaved) + raiseable = ActiveRecord::RecordNotSaved if raiseable.nil? + success = save + raise raiseable unless success + success end - + end \ No newline at end of file lib/save_or_raise.rb @@ -2,6 +2,8 @@ ENV["RAILS_ENV"] = "test" require File.expand_path(File.dirname(__FILE__) + "/../config/environment") require 'test_help' +require "#{File.dirname(__FILE__)}/../init" + class Test::Unit::TestCase # Transactional fixtures accelerate your tests by wrapping each test method # in a transaction that's rolled back on completion. This ensures that the test/test_helper.rb @@ -1,9 +1,189 @@ require File.dirname(__FILE__) + '/../test_helper' class SaveOrRaiseTest < Test::Unit::TestCase + fixtures :raises_posts - def test_stuff - assert true + # + # regular Rails behaviour + # + + def test_new_save + rp = RaisesPost.new + assert !rp.save + assert_raises(ActiveRecord::RecordInvalid) { + rp.save! + } + + rp.title = "Title" + assert rp.save + assert rp.save! + end + + def test_changed_save + rp = raises_posts(:hello) + assert_equal "Hello World!", rp.title + + rp.title = "" + assert !rp.save + assert_raises(ActiveRecord::RecordInvalid) { + rp.save! + } + + rp.title = "Goodbye" + assert rp.save + assert rp.save! + end + + def test_unchanged_save + rp = raises_posts(:hello) + assert_equal "Hello World!", rp.title + + rp.title = "Hello World!" + assert rp.save + assert rp.save! + end + + # + # save_or_raise + # + + def test_new_save_or_raise + rp = RaisesPost.new + assert_raises(ActiveRecord::RecordNotSaved) { + rp.save_or_raise + } + + rp.title = "Title" + assert rp.save_or_raise + end + + def test_changed_save_or_raise + rp = raises_posts(:hello) + assert_equal "Hello World!", rp.title + + rp.title = "" + assert_raises(ActiveRecord::RecordNotSaved) { + rp.save_or_raise + } + + rp.title = "Goodbye" + assert rp.save_or_raise + end + + def test_unchanged_save_or_raise + rp = raises_posts(:hello) + assert_equal "Hello World!", rp.title + + rp.title = "Hello World!" + assert rp.save_or_raise + end + + # + # save_or_raise(nil) + # + + def test_new_save_or_raise_nil + rp = RaisesPost.new + assert_raises(ActiveRecord::RecordNotSaved) { + rp.save_or_raise(nil) + } + + rp.title = "Title" + assert rp.save_or_raise(nil) + end + + def test_changed_save_or_raise_nil + rp = raises_posts(:hello) + assert_equal "Hello World!", rp.title + + rp.title = "" + assert_raises(ActiveRecord::RecordNotSaved) { + rp.save_or_raise(nil) + } + + rp.title = "Goodbye" + assert rp.save_or_raise(nil) + end + + def test_unchanged_save_or_raise_nil + rp = raises_posts(:hello) + assert_equal "Hello World!", rp.title + + rp.title = "Hello World!" + assert rp.save_or_raise(nil) + end + + # + # save_or_raise("woops!") + # + + def test_new_save_or_raise_message + rp = RaisesPost.new + assert_raises(RuntimeError,"woops!") { + rp.save_or_raise("woops!") + } + + rp.title = "Title" + assert rp.save_or_raise("woops!") + end + + def test_changed_save_or_raise_message + rp = raises_posts(:hello) + assert_equal "Hello World!", rp.title + + rp.title = "" + assert_raises(RuntimeError,"woops!") { + rp.save_or_raise("woops!") + } + + rp.title = "Goodbye" + assert rp.save_or_raise("woops!") + end + + def test_unchanged_save_or_raise_message + rp = raises_posts(:hello) + assert_equal "Hello World!", rp.title + + rp.title = "Hello World!" + assert rp.save_or_raise("woops!") + end + + # + # save_or_raise(CustomException) + # + + class CustomException < StandardError + end + + def test_new_save_or_raise_exception + rp = RaisesPost.new + assert_raises(CustomException) { + rp.save_or_raise(CustomException) + } + + rp.title = "Title" + assert rp.save_or_raise(CustomException) + end + + def test_changed_save_or_raise_exception + rp = raises_posts(:hello) + assert_equal "Hello World!", rp.title + + rp.title = "" + assert_raises(CustomException) { + rp.save_or_raise(CustomException) + } + + rp.title = "Goodbye" + assert rp.save_or_raise(CustomException) + end + + def test_unchanged_save_or_raise_exception + rp = raises_posts(:hello) + assert_equal "Hello World!", rp.title + + rp.title = "Hello World!" + assert rp.save_or_raise(CustomException) end end \ No newline at end of file test/unit/save_or_raise_test.rb 2842215ca54d6b23fb4b15243bbda29eae499d52 Ryan Lowe ryanlowe@gmail.com http://github.com/ryanlowe/save_or_raise/commit/3d47934779fb8783dae85b30ef2507c6aa8eab98 3d47934779fb8783dae85b30ef2507c6aa8eab98 2008-05-25T16:17:33-07:00 2008-05-25T16:17:33-07:00 finished first rough implementation 1b2abad4ffbc3c0738fc466e25d34e59b8f112c5 Ryan Lowe ryanlowe@gmail.com