after_commit does not work as expected in nested transactions

[averell23]

We are using aasm with activerecord and mysql/postgres for persistence. Today I found that the after_commit hook does not do what it says on the label, when you are in a nested transaction.

What happens

The hook is called after the aasm_transaction is complete, but before the outermost transaction is completed. This means that it will be called after a RELEASE SAVEPOINT but before the database transaction is COMMITed to the database.

What I expected

I had expected that the hook is only called after the database transaction COMMIT is done, that is, after the outermost database transaction is complete. This is also how the ActiveRecord after_commit hook works.

Was this means

Currently in an after_commit callback

• The database state may only be visible from the current thread (e.g. not in asynchronous processes)
• The current state may not actually be persisted, and can still be rolled back if an outer transaction fails

See the code

aasm/lib/aasm/persistence/orm.rb

Line 134 in 2621948

event.fire_callbacks(:after_commit, self, *args)

[caalberts]

@averell23 I'm also facing this issue in my application. I'm curious if you managed to work around this issue, and how.

I have an aasm after_commit hook which spawns a sidekiq background job, taking in the ActiveRecord object id. Something like: SomeJob.perform_async(self.id)

I have occasionally encountered situation where the job is picked up by Sidekiq worker, before the object is persisted to the database, and the job fails with error saying ActiveRecord::RecordNotFound: Couldn't find Object with 'id'=123.

[averell23]

You can mitigate by not having calling the state change within another transaction, the hook works at expected if you call it outside a db transaction.

You could also work with the ActiveRecord.after_commit hook, but this would involve some manual work...

[FX-HAO]

A workaround

class AfterCommitWrap
  # If not in a transaction, the block will be executed instantly.
  def self.after_commit(&block)
    ActiveRecord::Base.transaction do
      ActiveRecord::Base.connection.add_transaction_record(new(&block))
    end
  end
end

event :complete, after_commit: :after_completion do
  transitions from: %i[checkout processing], to: :completed
end

def after_completion
  AfterCommitWrap.after_commit do
    # your code here
  end
end

I'd like someone could help to fix this issue :)

[stokarenko]

#666 has been reverted.

#668 will fix the issue once again, but without explicit AR dependency.

[mquan]

Any idea when a new version with the fix will be released?

[anilmaurya]

@mquan Thank you for the reminder

Just released AASM 5.1.0 with the fix

[yugandharbandi2220]

@anilmaurya It's not working for me even after upgrading to the latest version. In my case, I'm doing multiple saves inside a single transaction. And, the after_commit hook is getting triggered before COMMIT

[stokarenko]

@anilmaurya did you added after_commit_everywhere gem as explicit Gemfile dependency?

As per Readme,

Please note that :after_commit AASM callbacks behaves around custom implementation of transaction pattern rather than a real-life DB transaction. This fact still causes the race conditions and redundant callback calls within nested transaction. In order to fix that it's highly recommended to add gem 'after_commit_everywhere', '~> 1.0' to your Gemfile.

[yugandharbandi2220]

@stokarenko my bad, missed this. It's working after adding the dependency. Thanks for the help