A way to wrap the default thread executor

[ximus]

a ruthlessly handy library thank you,

I make use of it to speed up generating database seeds in a rails app (db/seeds.rb) file.

as such:

users = [
  {
    display_name: 'John McTest',
    email: 'test@example.com',
    password: password,
  },
  # ...
].in_threads.with_progress('users').map do |entry|
  User.create!(entry)
end

In order to make use of database connections across threads, one needs to wrap each block with ActiveRecord::Base.connection_pool.with_connection.

For readability concerns, I would like to avoid sprinkling ActiveRecord::Base.connection_pool.with_connection throughout my seeds file.

Right now I use the following heavy handed global workaround:

require 'in_threads'

InThreads::Pool.class_eval do
  def run(&block)
    wrapped = ->{ ActiveRecord::Base.connection_pool.with_connection { block.call } }
    @queue.push(wrapped)
  end
end

I was wondering if there is a better, recommended way of handling this situation? Maybe a way to configure (or wrap) the default thread execution? Or if I could easily write a new in_db_threads helper that would behave like in_threads, but wrap with activerecord, but that seems impossible without monkey patching this gem.

[toy]

Thank you 😄

Currently library doesn't have any supported way to hook into the process.
The workaround looks fine, only problem it being a monkey patch if/when something changes.
I checked introducing another wrapper (.in_threads.with_progress('users').with_db.), but looks like it will not be simple, so best way would be to introduce hooks like .in_threads(around_each: proc{ |&block| ….with_connection(&block) }) and then you could add a method like in_db_threads to wrap it.

[ximus]

Thanks for the response.

If comes a stage when I need to get rid of the patch, I'll happily try implementing that hook idea.
I'll let you decide if you want to keep this issue open to track the idea.