How to exclude all models from engine?

[bjensen]

I tried adding this to the apartment initializer:

engine_models = myEngine.constants.map {|c| myEngine.const_get(c) }.select do |const|
  const.class == Class && const < ActiveRecord::Base
end

config.excluded_models = %w[User] + engine_models

This works perfectly when run in the console, however engine_models is empty when its being executed as part of initialisation. Does anyone have a good idea?

This is in Rails 6.0.2.1

[jean-francois-labbe]

Hi @bjensen I think this is because in development classes are lazy loaded so when the initializer is executed models are not loaded yet.

[bjensen]

I think you are right..but do you have any suggestions as to how to get it working in development except for actually having to cut and paste every model name and remember to add to this list whenever we add a new model etc?

[jean-francois-labbe]

I don't have the solution for this issue, but you should check rails eager_loading: https://guides.rubyonrails.org/autoloading_and_reloading_constants.html#eager-loading

[rpbaltazar]

@bjensen You might be able to get around with something close to what you have:

engine_models = myEngine.constants.map {|c| myEngine.const_get(c) }.select do |const|
const.class == Class && const < ActiveRecord::Base
end

engine_models.each do {|em| require em }

config.excluded_models = %w[User] + engine_models

Out of curiosity, what is the use case behind this?

EDIT: Forget what i just said. I've read through the thing again... I don't think that you'll be able to get around it without loading the classes.

The other option (more prone to errors) is to try to convert the table names onto models. Eg.

models = ActiveRecord::Base.connection.tables.map do |model|
  begin
    model.classify.constantize
  rescue NameError => e
    nil
  end
end

models.compact!

[rjayroach]

Does ActiveRecord::Base.connection.tables get the job done?

[rpbaltazar]

Closing this as it doesn't seem needed anyhow else. If this becomes an issue we can look at the use case