Fix many_to_many when one of the models has a prefix to the intersection model association

[bguban]

Fix many_to_many when one of the models is under a namespace and has a prefix to the intersection model association.

class Hc::Validator < ApplicationRecord
has_many :validator_universes
has_many :universes, through: :validator_universes, inverse_of: :hc_validators
end

class Hc::ValidatorResource < ApplicationResource
many_to_many :universes, resource: UniverseResource, foreign_key: { hc_validator_universes: :validator_id }
end

class Hc::ValidatorUniverse < ApplicationRecord
belongs_to :validator
belongs_to :universe
end

class Universe < ApplicationRecord
has_many :hc_validator_universes, class_name: 'Hc::ValidatorUniverse'
has_many :hc_validators, class_name: 'Hc::Validator', through: :hc_validator_universes, source: :validator
end

class UniverseResource < ApplicationResource
many_to_many :hc_validators, resource: Hc::ValidatorResource, foreign_key: { validator_universes: :universe_id }
end

[jkeen]

@bguban Mind adding a test for this? I'm not quite understanding the issue

[bguban]

Hi @jkeen. sorry for the late response. the problem is pretty simple. graphiti fails with

Graphiti::Errors::SideloadQueryBuildingError (          Hc::ValidatorResource: error occurred while sideloading "universes"!

          The error was raised while attempting to build the scope for the associated Resource.

          Read more about sideload scoping here: www.graphiti.dev/guides/concepts/resources#customizing-scope

          Here's the original, underlying error:

          NoMethodError: undefined method `klass' for nil
          /Users/bguban/.rvm/gems/ruby-3.3.3@market_data/gems/graphiti-1.3.9/lib/graphiti/adapters/active_record/many_to_many_sideload.rb:4:in `through_table_name'
...

when I make a request like /api/v1/hc/validators?include=universes. It's because ValidatorResource and ValidatorUniverse is within 'Hc' namespace but the universe isn't.

Honestly say it's not clear why it takes parent_resource_class instead of just take resource_class. Hopefully soon I'll have time to get dipper into it