Fix nested namespaces parsing and resource resolving

[elvanja]

With this setup:

class Managing::Profile < ActiveRecord::Base
  belongs_to :company
end

class Company < ActiveRecord::Base
  belongs_to :default_managing_profile, class_name: '::Managing::Profile'
end

class Api::V1::BaseResource < JSONAPI::Resource
  abstract

  attributes :created_at, :updated_at

  def self.updatable_fields(context)
    super - [:created_at, :updated_at]
  end

  def self.creatable_fields(context)
    super - [:created_at, :updated_at]
  end
end

class Api::V1::Managing::ProfileResource < Api::V1::BaseResource
  model_name 'Managing::Profile'
  attributes :name
end

class Api::V1::CompanyResource < Api::V1::BaseResource
  model_name 'Company'
  attributes :name
  has_one :default_managing_profile, class_name: 'Managing::Profile'
end

, there were several things that didn't work:

• on startup, without class_name: 'Managing::Profile' in CompanyResource, it would report that it could not find related model
• requesting included profile via http://localhost:3000/api/v1/companies/3?include=default_managing_profile, it would also break, unable to find the related resource
• on posting a new company, with relation to existing managing profile, it would again break, for the same reason

example of post payload:

{
  "data": {
    "attributes": {
      "name": "Dummy"
    },
    "relationships": {
      "default_managing_profile": {
        "data": {
          "type": "profiles",
          "id": "3"
        }
      }
    },
    "type": "companies"
  }
}

I also tried setting the data type for default_managing_profile to one of:

• managing/profiles
• /managing/profiles
• Managing::Profile
• managing_profiles

and probably some other too, but without luck.

The fix in resource.rb solved first two issues. The fix in request_parser.rb fixed the last one. I tried adding related tests, but could not find a simple way to test the last issue.

Hopefully this makes sense 😄

P.S. I've noticed that RequestParser#parse_to_many_relationship has a bit different logic than parse_to_one_relationship so maybe I'm missing something here. Maybe there is a way to accomplish the desired outcome without this fix?

P.P.S. Possibly related to #893 and #927.

[lgebhardt]

@elvanja Thanks!

[kented]

This issue was causing me some pain. Thanks for the fix, @elvanja