YABI — Yet Another Base Interactor
A tiny base class for service objects/interactors built on dry-monads, dry-initializer, and dry-validation, plus a minimal base contract.
Installation
Add to your Gemfile:
gem 'yabi', git: 'https://example.com/yabi.git'Require the gem (Rails autoloading works too):
require 'yabi'By default the gem exposes Yabi::BaseInteractor plus shims BaseInteractor and BaseService (only defined if missing) to ease migration of existing code.
Usage
class Users::Questions::Create < BaseInteractor
option :question_text
class ValidationContract < BaseContract
params { required(:question_text).filled(:string) }
end
def call
Success(question_text.upcase)
end
end
Users::Questions::Create.call(question_text: 'hello')
# => Success(\"HELLO\")Contracts
Pass a contract via the contract: keyword when calling, or define an inner ValidationContract constant. Validation runs before call; failures return Failure(errors).
YABI ships with Yabi::BaseContract (also available as BaseContract) which is a light wrapper around Dry::Validation::Contract. It uses the :i18n messages backend by default and loads the built‑in dry-validation translations. Customize it in your app if you want different load paths or locales:
class ApplicationContract < Yabi::BaseContract
config.messages.default_locale = :es
config.messages.load_paths << Rails.root.join('config/locales/es.yml')
endError messages & I18n
The gem ships an English locale file at config/locales/en.yml and loads it automatically. Errors raised inside YABI (e.g., for unexpected positional arguments) are translated via I18n.t('yabi.errors.*'). Override translations by adding your own locale files earlier in I18n.load_path or by setting I18n.locale.
Helpers
-
safe_call { ... }wraps a block intoTryand returns a Result. -
in_transaction { ... }delegates toActiveRecord::Base.transactionwhen ActiveRecord is available.
Attribute capture
Yabi::BaseInteractor uses dry_initializer.attributes(self) to collect declared options/params for validation instead of scraping every instance variable. This avoids leaking internal state while keeping compatibility with dry-initializer defaults. A fallback to the previous instance-variable scan remains for non-dry objects.
Example: HTTP request interactor (not included in the gem)
The gem no longer ships an HTTP interactor to avoid adding Faraday as a runtime dependency. If you want one, you can copy/paste or adapt the example below. Remember to add Faraday (or your preferred adapter) to your own Gemfile.
require 'faraday'
require 'uri'
class Integrations::Http::Requests::Make < BaseInteractor
option :http_method
option :url
option :request_params, default: -> { {} }
option :request_headers, default: -> { {} }
option :options, default: -> { {} }
class ValidationContract < BaseContract
params do
required(:http_method).filled(:string)
required(:url).filled(:string)
optional(:request_params)
optional(:request_headers)
optional(:options)
end
rule(:http_method) do
key.failure('is not a supported HTTP method') unless %w[get post put patch delete].include?(value.to_s.downcase)
end
rule(:url) do
key.failure('is not a valid URL') unless value.to_s.match?(URI::DEFAULT_PARSER.make_regexp)
end
end
def call
response = yield safe_call { faraday_client.public_send(http_method.to_sym, '', prepared_request_params) }
Success(response)
end
private
def faraday_client
Faraday.new(url:, headers: request_headers, **options) do |faraday|
faraday.request :url_encoded
faraday.adapter Faraday.default_adapter
end
end
def prepared_request_params
request_params.respond_to?(:to_h) ? request_params.to_h : request_params
end
end
Integrations::Http::Requests::Make.call(
http_method: 'get',
url: 'https://jsonplaceholder.typicode.com/posts/1'
).either(
->(response) { puts \"Success: #{response.status}\" },
->(error) { puts \"Error: #{error}\" }
)This interactor is only an example; include it in your own app if desired and add Faraday (or another HTTP client) to your dependencies.
Development
bundle install
bundle exec rspecLicense
MIT