How to force Rails ActiveRecord to commit a transaction flush

activerecord, ruby-on-rails, transactions

Solution

ActiveRecord uses `#transaction` to create a block that begins and either rolls back or commits a transaction. I believe that would help your issue. Essentially (presuming Task is an ActiveRecord class):

Task.transaction do
  new_task = Task.create(...)
end

BackgroundQueue.enqueue(new_task)

You could also go directly to the `#connection` underneath with:

Task.connection.commit_db_transaction

That's a bit low-level, though, and you have to be pretty confident about the way the code is being used. `#after_commit` is the best answer, even if it takes a little rejiggering of the code to make it work. If it won't work for certain, then these two approaches should help.

Problem

Is it possible to force ActiveRecord to push/flush a transaction (or just a save/create)? I have a clock worker that creates tasks in the background for several task workers. The problem is, the clock worker will sometimes create a task and push it to a task worker before the clock worker information has been fully flushed to the db which causes an ugly race condition. Using after_commit isn't really viable due to the architecture of the product and how the tasks are generated. So in short, I need to be able to have one worker create a task and flush that task to the db.

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