Engine loads ActiveRecord::Base at require time, breaking host apps' initializer-configured Active Record encryption

[phanilkumar]

Summary

lib/solid_objects/engine.rb loads SolidObjects::Record (a subclass of ActiveRecord::Base) at require time:

# lib/solid_objects/engine.rb
require_relative "../../app/models/solid_objects/record"

Because lib/solid_objects.rb is required during Bundler.require, this forces ActiveRecord::Base to load before the host Rails app boots. That changes the timing of every ActiveSupport.on_load(:active_record) / on_load(:active_record_encryption) hook in the host app from "first real AR use, after initializers" to "immediately, during railtie setup" — with at least one concrete breakage:

Observed breakage: Active Record encryption silently loses its keys

Rails applies encryption config via (activerecord/lib/active_record/railtie.rb):

initializer "active_record_encryption.configuration" do |app|
  ActiveSupport.on_load(:active_record_encryption) do
    ActiveRecord::Encryption.configure(
      primary_key: app.credentials.dig(:active_record_encryption, :primary_key),
      ...
      **app.config.active_record.encryption
    )
  end
end

Normally that hook fires on first AR use, long after config/initializers/* have populated config.active_record.encryption. With solid_objects in the bundle, AR is already loaded when the railtie registers the hook, so it fires right there — before config/initializers run. Any app that assigns its encryption keys in an initializer (a common pattern, e.g. to support env-var key rotation with a credentials fallback) gets Encryption.configure called with nils, the initializer's later assignment is silently discarded, and every encrypted attribute raises at first use:

ActiveRecord::Encryption::Errors::Configuration:
  Missing Active Record encryption credential: active_record_encryption.deterministic_key

The failure is far from the cause (model specs unrelated to solid_objects), which made it expensive to trace. Verified on solid_objects 0.13.0, Rails 8.1.3.1, Ruby 4.0.6: adding the gem to the Gemfile breaks these specs with no other change; removing it (or moving the app's key assignment into the application class body) fixes them.

Encryption is just the visible symptom — pre-loading AR at require time shifts the semantics of every deferred on_load(:active_record) hook in the host app and other gems.

Suggested fix

Defer the model load until Active Record actually loads, the way engines conventionally do:

# lib/solid_objects/engine.rb
module SolidObjects
  class Engine < ::Rails::Engine
    ...
    initializer "solid_objects.record" do
      ActiveSupport.on_load(:active_record) do
        require_relative "../../app/models/solid_objects/record"
      end
    end
  end
end

(and similarly audit lib/solid_objects.rb's top-level require "active_record" — requiring the framework is fine, but nothing should touch ActiveRecord::Base until on_load fires). The other models under app/models/solid_objects/ appear to load lazily via the engine's autoload paths already; Record is the one eager exception.

Host-app workaround

Move encryption key assignment out of config/initializers into the Application class body in config/application.rb, which executes before railtie initializers regardless of AR load timing.

---

Found while evaluating solid_objects for a production Rails 8.1 e-commerce app (the payment-link recovery actor worked beautifully otherwise — thanks for the library).