Add task db:prepare:with_data

[Floppy]

This is my attempt at #215. At the moment there's lots of code copied out of rails, it needs DRYing up a bit, and it needs tests adding. I'll work on it some more before making this ready for review, but it seems to work...

This is basically a direct copy of ActiveRecord::Tasks::DatabaseTasks#prepare_all, but instead of calling migrate, it calls migrate_with_data (refactored out of databases.rake), and adds data-appropriate calles into schema loading and dumping code as well.

Original code is at https://github.com/rails/rails/blob/5ed37b35d666b833aeccb14a4cacd2926251232d/activerecord/lib/active_record/tasks/database_tasks.rb#L176

The code is on a feature branch off the 9.1.0 tag at the moment, as I know there's a lot of work going on with v10, and I didn't want to start stepping on toes there; also, that's the version I'm using in production so that's where I needed it :)

[Floppy]

This is definitely working reliably for me, so I'm making the PR ready to review, even though it could still do with some tidying up.

[santiagodoldan]

It would be awesome to release this feature 💯

[Floppy]

I should be able to get back to this shortly! I've been using it in production for ages 👍

[jgmontoya]

@Floppy @wildmaples any updates on this? Any chance of getting it released soon?

[Floppy]

I've just rebased this against the latest main, so it should be up to date and work with Rails 7.1. I'll test it for a while and report back.

[Floppy]

Seems to be working fine...

[ignaciogrondona]

Thank you @Floppy for this! Any chance it gets merged anytime soon?

[Floppy]

It's working happily in production on my site, so it all seems fine still. Happy to make any changes based on feedback from @ilyakatz or other maintainers! I guess it depends on v10 work perhaps?

[jgmontoya]

I noticed #319 got merged, not sure what the differences are with this one

[ilyakatz]

Oh, i thought it would close this this PR. Basically, cherry picked so that I could update versions. So it's in, thanks for your contribution @Floppy !

[ilyakatz]

Fixed by #319

[Floppy]

Oh, superb, thanks @ilyakatz!

[jgmontoya]

@ilyakatz @Floppy quick question, just because I'm curious: This PR had some stuff that didn't quite make it to the merged version

i.e.:

# lib/data_migrate/database_tasks.rb
def with_temporary_pool(db_config)
  original_db_config = migration_class.connection_db_config
  pool = migration_class.establish_connection(db_config)
  yield pool
ensure
  migration_class.establish_connection(original_db_config)
end

def migration_class # :nodoc:
  ActiveRecord::Base
end

def migration_connection # :nodoc:
  migration_class.connection
end

def self.prepare_all_with_data
...

What was this about? 😅

EDIT: I see now that with_temporary_pool, migration_class, migration_connection are already defined

[ilyakatz]

oh, oops, did i mess something up? I checked out the branch from @Floppy and created a new branch. But looks like I messed something up. Do you mind creating a new PR, if you update the versions numbers, I can just merge as is and not mock around branches

[jgmontoya]

@ilyakatz I added the missing task definition here: #321