feat: add OpenAI translator (#519)

README.md

@@ -117,6 +117,17 @@ $ i18n-tasks translate-missing --backend=yandex
 $ i18n-tasks translate-missing --from=en es fr
 ```
 
+### OpenAI Translate missing keys
+
+Translate missing values with OpenAI ([more below on the API key](#openai-translation-config)).
+
+```console
+$ i18n-tasks translate-missing --backend=openai
+
+# accepts from and locales options:
+$ i18n-tasks translate-missing --from=en es fr
+```
+
 ### Find usages
 
 See where the keys are used with `i18n-tasks find`:
@@ -424,6 +435,17 @@ translation:
   yandex_api_key: <Yandex API key>
 ```
 
+<a name="openai-translation-config"></a>
+### OpenAI Translate
+
+`i18n-tasks translate-missing` requires a OpenAI API key, get it at [OpenAI](https://openai.com/).
+
+```yaml
+# config/i18n-tasks.yml
+translation:
+  openai_api_key: <OpenAI API key>
+```
+
 ## Interactive console
 
 `i18n-tasks irb` starts an IRB session in i18n-tasks context. Type `guide` for more information.

config/locales/en.yml

@@ -112,6 +112,12 @@ en:
     missing:
       details_title: Value in other locales or source
       none: No translations are missing.
+    openai_translate:
+      errors:
+        no_api_key: >-
+          Set OpenAI API key via OPENAI_API_KEY environment variable or translation.openai_api_key
+          in config/i18n-tasks.yml. Get the key at https://openai.com/.
+        no_results: OpenAI returned no results.
     remove_unused:
       confirm:
         one: "%{count} translation will be removed from %{locales}."

config/locales/ru.yml

@@ -111,6 +111,12 @@ ru:
     missing:
       details_title: На других языках или в коде
       none: Всё переведено.
+    openai_translate:
+      errors:
+        no_api_key: |-
+          Установить ключ API Яндекса с помощью переменной среды OPENAI_API_KEY или translation.openai_api_key
+           в config / i18n-tasks.yml. Получите ключ по адресу https://openai.com/.
+        no_results: Яндекс не дал результатов.
     remove_unused:
       confirm:
         few: Переводы (%{count}) будут удалены из %{locales}.

lib/i18n/tasks/configuration.rb

@@ -66,6 +66,7 @@ def translation_config
       conf[:deepl_api_key] = ENV['DEEPL_AUTH_KEY'] if ENV.key?('DEEPL_AUTH_KEY')
       conf[:deepl_host] = ENV['DEEPL_HOST'] if ENV.key?('DEEPL_HOST')
       conf[:deepl_version] = ENV['DEEPL_VERSION'] if ENV.key?('DEEPL_VERSION')
+      conf[:openai_api_key] = ENV['OPENAI_API_KEY'] if ENV.key?('OPENAI_API_KEY')
       conf[:yandex_api_key] = ENV['YANDEX_API_KEY'] if ENV.key?('YANDEX_API_KEY')
       conf
     end

lib/i18n/tasks/translation.rb

@@ -2,20 +2,23 @@
 
 require 'i18n/tasks/translators/deepl_translator'
 require 'i18n/tasks/translators/google_translator'
+require 'i18n/tasks/translators/openai_translator'
 require 'i18n/tasks/translators/yandex_translator'
 
 module I18n::Tasks
   module Translation
     # @param [I18n::Tasks::Tree::Siblings] forest to translate to the locales of its root nodes
     # @param [String] from locale
-    # @param [:deepl, :google, :yandex] backend
+    # @param [:deepl, :openai, :google, :yandex] backend
     # @return [I18n::Tasks::Tree::Siblings] translated forest
     def translate_forest(forest, from:, backend: :google)
       case backend
       when :deepl
         Translators::DeeplTranslator.new(self).translate_forest(forest, from)
       when :google
         Translators::GoogleTranslator.new(self).translate_forest(forest, from)
+      when :openai
+        Translators::OpenAiTranslator.new(self).translate_forest(forest, from)
       when :yandex
         Translators::YandexTranslator.new(self).translate_forest(forest, from)
       else

lib/i18n/tasks/translators/openai_translator.rb

@@ -0,0 +1,100 @@
+# frozen_string_literal: true
+
+require 'i18n/tasks/translators/base_translator'
+
+module I18n::Tasks::Translators
+  class OpenAiTranslator < BaseTranslator
+    # max allowed texts per request
+    BATCH_SIZE = 50
+
+    def initialize(*)
+      begin
+        require 'openai'
+      rescue LoadError
+        raise ::I18n::Tasks::CommandError, "Add gem 'ruby-openai' to your Gemfile to use this command"
+      end
+      super
+    end
+
+    def options_for_translate_values(from:, to:, **options)
+      options.merge(
+        from: from,
+        to: to
+      )
+    end
+
+    def options_for_html
+      {}
+    end
+
+    def options_for_plain
+      {}
+    end
+
+    def no_results_error_message
+      I18n.t('i18n_tasks.openai_translate.errors.no_results')
+    end
+
+    private
+
+    def translator
+      @translator ||= OpenAI::Client.new(access_token: api_key)
+    end
+
+    def api_key
+      @api_key ||= begin
+        key = @i18n_tasks.translation_config[:openai_api_key]
+        fail ::I18n::Tasks::CommandError, I18n.t('i18n_tasks.openai_translate.errors.no_api_key') if key.blank?
+
+        key
+      end
+    end
+
+    def translate_values(list, from:, to:)
+      results = []
+
+      list.each_slice(BATCH_SIZE) do |batch|
+        translations = translate(batch, from, to)
+
+        results << JSON.parse(translations)
+      end
+
+      results.flatten
+    end
+
+    def translate(values, from, to) # rubocop:disable Metrics/MethodLength
+      messages = [
+        {
+          role: 'system',
+          content: "You are a helpful assistant that translates content from the #{from} to #{to} locale in an i18n
+          locale array. The array has a structured format and contains multiple strings. Your task is to translate
+          each of these strings and create a new array with the translated strings. Keep in mind the context of all
+          the strings for a more accurate translation.\n"
+        },
+        {
+          role: 'user',
+          content: "Translate this array: \n\n\n"
+        },
+        {
+          role: 'user',
+          content: values.to_json
+        }
+      ]
+
+      response = translator.chat(
+        parameters: {
+          model: 'gpt-3.5-turbo',
+          messages: messages,
+          temperature: 0.7
+        }
+      )
+
+      translations = response.dig('choices', 0, 'message', 'content')
+      error = response['error']
+
+      fail "AI error: #{error}" if error.present?
+
+      translations
+    end
+  end
+end