How to set up shared database in test environment

[kennyki]

Hi, I was trying to add a shared model to an existing tenanted application. I have a setup similar to this test scenario

This is how my database.yml looks like (I started to add shared):

default: &default
  adapter: sqlite3
  max_connections: <%= ENV.fetch("RAILS_MAX_THREADS") { 5 } %>
  timeout: 5000
development:
  primary:
    <<: *default
    database: storage/development/%{tenant}.sqlite3
    tenanted: true
  shared:
    <<: *default
    database: storage/development/shared.sqlite3
    migrations_paths: db/shared_migrations
test:
  primary:
    <<: *default
    database: storage/test/%{tenant}.sqlite3
    tenanted: true
  shared:
    <<: *default
    database: storage/test/shared.sqlite3
    migrations_paths: db/shared_migrations

And the models:

class ApplicationRecord < ActiveRecord::Base
  primary_abstract_class
  tenanted
end

class SharedApplicationRecord < ActiveRecord::Base
  self.abstract_class = true
  connects_to database: { writing: :shared, reading: :shared }
end

In development environment, everything runs fine (db migration ran, and the app works as expected). However, when I run test (minitest) on any of my models, it will result in

ActiveRecord::DatabaseAlreadyExists: Cannot use an untenanted ActiveRecord::Base connection. If you have a model that inherits directly from ActiveRecord::Base, make sure to use 'subtenant_of'. In development, you may see this error if constant reloading is not being done properly. (ActiveRecord::DatabaseAlreadyExists)


Caused by:
ActiveRecord::Tenanted::NoTenantError: Cannot use an untenanted ActiveRecord::Base connection. If you have a model that inherits directly from ActiveRecord::Base, make sure to use 'subtenant_of'. In development, you may see this error if constant reloading is not being done properly. (ActiveRecord::Tenanted::NoTenantError)

Tasks: TOP => db:test:load_schema => db:test:purge
(See full trace by running task with --trace)
Migrations are pending. To resolve this issue, run:

        bin/rails db:migrate

You have 1 pending migration:

db/shared_migrations/20260131155848_create_organization_directories.rb

What could have been the cause? Any direction should I be looking at?

Thank you

[kennyki]

I'm using a workaround in the meantime - in test environment, the SharedApplicationRecord is connecting to the default test tenant instead.

The test database config now looks like:

test:
  <<: *default
  database: storage/test/%{tenant}.sqlite3
  migrations_paths:
    - db/migrations
    - db/shared_migrations
  tenanted: true

The model:

class SharedApplicationRecord < ActiveRecord::Base
  self.abstract_class = true

  if Rails.env.test?
    subtenant_of "ApplicationRecord"
  else
    connects_to database: { writing: :shared, reading: :shared }
  end
end

---

With this, the tests are running fine, but I'm not confident that it's the right way to do it.