Skooma

# spec/rails_helper.rb

RSpec.configure do |config|
  # ...
  Skooma.create_registry
  path_to_openapi = Rails.root.join("docs", "openapi.yml")
  config.include Skooma::RSpec[path_to_openapi], type: :request
end

# spec/openapi_spec.rb

require "rails_helper"

describe "OpenAPI document", type: :request do
  subject(:schema) { skooma_openapi_schema }

  it { is_expected.to be_valid_document }
end

# spec/requests/feed_spec.rb

require "rails_helper"

describe "/animals/:animal_id/feed" do
  let(:animal) { create(:animal, :unicorn) }

  describe "POST" do
    subject { post "/animals/#{animal.id}/feed", body:, as: :json }

    let(:body) { {food: "apple", quantity: 3} }

    it { is_expected.to conform_schema(200) }

    context "with wrong food type" do
      let(:body) { {food: "wood", quantity: 1} }

      it { is_expected.to conform_schema(422) }
    end
  end
end

# Validation Result:
#
#  {"valid"=>false,
#   "instanceLocation"=>"",
#   "keywordLocation"=>"",
#   "absoluteKeywordLocation"=>"urn:uuid:1b4b39eb-9b93-4cc1-b6ac-32a25d9bff50#",
#   "errors"=>
#     [{"instanceLocation"=>"",
#       "keywordLocation"=>
#         "/paths/~1animals~1{animalId}~1feed/post/responses/200"/
#           "/content/application~1json/schema/required",
#       "error"=>
#         "The object is missing required properties"/
#           " [\"animalId\", \"food\", \"amount\"]"}]}