pat / after_commit

A Ruby on Rails plugin to add an after_commit callback. This can be used to trigger things only after the entire transaction is complete.

after_commit

An ActiveRecord/Rails library to add before_commit, after_commit, before_rollback and after_rollback callbacks. These callbacks are focused on the transactions, instead of specific model actions. This is beneficial in situations where you are doing asynchronous processing and need committed objects.

Please note: Rails 3 (and thus, ActiveRecord 3) provides commit callbacks natively, so this library will remain just for versions 1.2.x to 2.x of ActiveRecord.

Installation

gem install after_commit

Usage

The following callbacks are provided:

• before_commit
• before_commit_on_create
• before_commit_on_update
• before_commit_on_save
• before_commit_on_destroy
• after_commit
• after_commit_on_create
• after_commit_on_update
• after_commit_on_save
• after_commit_on_destroy
• before_rollback
• after_rollback

You can use these just like you would any other callback:

class Article < ActiveRecord::Base
  after_commit :method_to_call_after_commit
  
  # ...
  
  private
  
  def method_to_call_after_commit
    # Do something knowing that the transaction is committed.
  end
end

In Tests

Keep in mind that transactions are finicky at best in tests, and so there’s a helper module to make after_commit play nicely in your testing context. You’ll need to add these two lines to your spec/test helper:

ActiveRecord::Base.send(:include, AfterCommit::AfterSavepoint)
ActiveRecord::Base.include_after_savepoint_extensions

Credits

This code first appeared in a blog post by Eli Miller, and was then included in Thinking Sphinx by Pat Allan, with modifications from Joost Hietbrink. The code was then put on GitHub as a plugin by Nick Muerdter, and many people forked and added their own contributions.

This version (maintained by Pat Allan) includes the following patches:

• Callbacks for specific types of actions (create, update, destroy) (DeLynn Berry)
• Fixes to extra callbacks (Xavier Shay)
• Thread-safety (Dmitry Galinsky)
• after_rollback callback (Justin Balthrop)
• Test environment fix (Pivotal Labs)
• Scoping callbacks to specific connections (Mat Brown)
• before_* callbacks (Trotter Cashion)
• Gemspec and extended tests, works as a plugin, doesn’t load ActiveRecord hooks twice, doesn’t add Test environment hook automatically. (David Yip)
• Exception propagation (George Ogata)
• Keeping callbacks focused on the correct transactions (Benjamin Stein)
• Using savepoints for test helper (Lars Klevan and Joel Chippindale)
• Only tracking objects from classes that have appropriate callbacks; Adding after/before_commit_on_save to cover creates and updates but not destroys (Jason Weathered)
• Fixing up exception handling and savepoints in the test helper, and cleaning up successful transactions correctly (Identified).
• Improved JRuby support (Kevin Menard)
• Stop transaction failures in tests (Ochko)

after_commit's Issues

Allow inline after_commit do blocks <-> make ar_after_transaction obsolote

I have a similar project (ar_after_transaction)[https://github.com/grosser/ar_after_transaction] that fixes the same problems, but also adds a after_transaction do block style callback, so users can e.g.

after_create :do_stuff, :oops

def do_stuff
  after_transaction do
    send_an_email # cannot be rolled back
  end
  comments.create(...) # will be rolled back
end

Is it possilbe to include this behavior -> id like to mark the project as obsolete and just link here.

1.0.9 breaks my tests... fixed it by adding gem "after_commit", "1.0.8"

I recently did a gem update... and 1.0.9 installed itself

Then all my tests broke with reuse of transaction messages and failure to reset Sham.

I'm using test::unit with transactional fixtures and Machinist (in case that matters)

i've fixed the version at 1.0.8 in my Gemfile and I'm back in action.

This could be related to the change in dependency ... my Gemfile.lock says activerecord < 3.0.0 with 1.0.8, but < 3.0.0, >=1.15.6 with 1.0.9.

so... to fix my test breakage i added this line to Gemfile
gem "after_commit", "1.0.8"

before this trouble, after_commit was only added as a dependency and was not explicitly listed.

activerecord-jdbc-adapter 1.2.1 breaks compatibility

ArJdbc 1.2.0 works, but 1.2.1 gives me this traceback:

$ script/server -e production -p 3002
=> Booting Mongrel
=> Rails 2.3.14 application starting on http://0.0.0.0:3002

NameError: undefined method `commit_db_transaction' for module `ArJdbc::MySQL'
                     alias_method at org/jruby/RubyModule.java:2221
               alias_method_chain at /Users/nilbus/.rvm/gems/jruby-1.6.5@robertson/gems/activesupport-2.3.14/lib/active_support/core_ext/module/aliasing.rb:33
                         included at /Users/nilbus/.rvm/gems/jruby-1.6.5@robertson/gems/after_commit-1.0.10/lib/after_commit/connection_adapters.rb:74
                      module_eval at org/jruby/RubyModule.java:2242
                         included at /Users/nilbus/.rvm/gems/jruby-1.6.5@robertson/gems/after_commit-1.0.10/lib/after_commit/connection_adapters.rb:4
                          include at org/jruby/RubyModule.java:2083
                             send at org/jruby/RubyKernel.java:2097
   include_after_commit_extension at /Users/nilbus/.rvm/gems/jruby-1.6.5@robertson/gems/after_commit-1.0.10/lib/after_commit/active_record.rb:29
  include_after_commit_extensions at /Users/nilbus/.rvm/gems/jruby-1.6.5@robertson/gems/after_commit-1.0.10/lib/after_commit/active_record.rb:20
                           (root) at /Users/nilbus/.rvm/gems/jruby-1.6.5@robertson/gems/after_commit-1.0.10/lib/after_commit.rb:81
                          require at org/jruby/RubyKernel.java:1038
                          require at /Users/nilbus/.rvm/gems/jruby-1.6.5@robertson/gems/activesupport-2.3.14/lib/active_support/dependencies.rb:184
                           (root) at /Users/nilbus/.rvm/gems/jruby-1.6.5@robertson/gems/after_commit-1.0.10/lib/after_commit.rb:2
                          require at org/jruby/RubyKernel.java:1038
                          require at /Users/nilbus/.rvm/gems/jruby-1.6.5@robertson/gems/thinking-sphinx-1.3.14/lib/thinking_sphinx.rb:68

after_commit_on_update with multiple updates to the same object per transaction

This issue is really biting us in the butt. I'm happy to commit a change to fix this, but I wanted to get some perspective before I do.

Here's the issue we're having:

we have a after_commit_on_update callback for a model. I've changed the callback to just print when it is called. Inside our code, we do something similar to this (of course these updates aren't right next to each other).

User.transaction do
  user.update_attribute(:first_name, "asdf")
  user.update_attribute(:last_name, "fdsa")
end

Will result in

CALLING COMMIT UPDATE
CALLING COMMIT UPDATE

Now, I admit that we probably shouldn't be doing these things, but we are, and it's hard to go through a relatively large codebase to fix these double-updated.

I think it makes sense to make the :committed_records_on_update collection only have one instance of an object in the collection, no matter how many times the object was updated inside the transaction. Thoughts?