DEV: Add the ability to translate a single piece of text

Author: nattsw

app/services/discourse_translator/provider/amazon.rb

@@ -140,6 +140,20 @@ def self.translate_translatable!(translatable, target_locale_sym = I18n.locale)
         end
       end
 
+      def self.translate_text!(text, target_locale_sym = I18n.locale)
+        begin
+          client.translate_text(
+            {
+              text: truncate(text),
+              source_language_code: "auto",
+              target_language_code: SUPPORTED_LANG_MAPPING[target_locale_sym],
+            },
+          )
+        rescue Aws::Translate::Errors::UnsupportedLanguagePairException
+          raise I18n.t("translator.not_supported")
+        end
+      end
+
       def self.client
         opts = { region: SiteSetting.translator_aws_region }
 

app/services/discourse_translator/provider/base_provider.rb

@@ -65,6 +65,10 @@ def self.translate_translatable!(translatable, target_locale_sym = I18n.locale)
         raise "Not Implemented"
       end
 
+      def self.translate_text(text, target_locale_sym = I18n.locale)
+        raise "Not Implemented"
+      end
+
       # Returns the stored detected locale of a post or topic.
       # If the locale does not exist yet, it will be detected first via the API then stored.
       # @param translatable [Post|Topic]

app/services/discourse_translator/provider/discourse_ai.rb

@@ -10,27 +10,13 @@ def self.language_supported?(detected_lang)
       end
 
       def self.detect!(topic_or_post)
-        unless required_settings_enabled
-          raise TranslatorError.new(
-                  I18n.t(
-                    "translator.discourse_ai.ai_helper_required",
-                    { base_url: Discourse.base_url },
-                  ),
-                )
-        end
+        required_settings_enabled!
 
         ::DiscourseAi::LanguageDetector.new(text_for_detection(topic_or_post)).detect
       end
 
       def self.translate_translatable!(translatable, target_locale_sym = I18n.locale)
-        unless required_settings_enabled
-          raise TranslatorError.new(
-                  I18n.t(
-                    "translator.discourse_ai.ai_helper_required",
-                    { base_url: Discourse.base_url },
-                  ),
-                )
-        end
+        required_settings_enabled!
 
         language = get_language_name(target_locale_sym)
         translated =
@@ -51,11 +37,25 @@ def self.translate_translatable!(translatable, target_locale_sym = I18n.locale)
         DiscourseTranslator::TranslatedContentNormalizer.normalize(translatable, translated)
       end
 
+      def self.translate_text!(text, target_locale_sym = I18n.locale)
+        required_settings_enabled!
+
+        language = get_language_name(target_locale_sym)
+        ::DiscourseAi::ShortTextTranslator.new(text, language).translate
+      end
+
       private
 
-      def self.required_settings_enabled
-        SiteSetting.translator_enabled && SiteSetting.translator_provider == "DiscourseAi" &&
-          SiteSetting.discourse_ai_enabled && SiteSetting.ai_helper_enabled
+      def self.required_settings_enabled!
+        unless SiteSetting.translator_enabled && SiteSetting.translator_provider == "DiscourseAi" &&
+                 SiteSetting.discourse_ai_enabled && SiteSetting.ai_helper_enabled
+          raise TranslatorError.new(
+                  I18n.t(
+                    "translator.discourse_ai.ai_helper_required",
+                    { base_url: Discourse.base_url },
+                  ),
+                )
+        end
       end
 
       def self.get_language_name(target_locale_sym)

app/services/discourse_translator/provider/google.rb

@@ -106,6 +106,11 @@ def self.translate_translatable!(translatable, target_locale_sym = I18n.locale)
         res["translations"][0]["translatedText"]
       end
 
+      def self.translate_text!(text, target_locale_sym = I18n.locale)
+        res = result(TRANSLATE_URI, q: text, target: SUPPORTED_LANG_MAPPING[target_locale_sym])
+        res["translations"][0]["translatedText"]
+      end
+
       def self.result(url, body)
         body[:key] = access_token
 

app/services/discourse_translator/provider/libre_translate.rb

@@ -105,6 +105,12 @@ def self.translate_translatable!(translatable, target_locale_sym = I18n.locale)
         res["translatedText"]
       end
 
+      def self.translate_text!(text, target_locale_sym = I18n.locale)
+        # Unsupported - see https://libretranslate.com/docs/#/translate/post_translate
+        # requires a source language
+        raise TranslatorError.new(I18n.t("translator.not_supported"))
+      end
+
       def self.get(url)
         begin
           response = Excon.get(url)

app/services/discourse_translator/provider/microsoft.rb

@@ -171,6 +171,18 @@ def self.translate_translatable!(translatable, target_locale_sym = I18n.locale)
         response_body.first["translations"].first["text"]
       end
 
+      def self.translate_text!(text, target_locale_sym = I18n.locale)
+        locale =
+          SUPPORTED_LANG_MAPPING[target_locale_sym] || (raise I18n.t("translator.not_supported"))
+
+        query = default_query.merge("to" => locale, "textType" => "html")
+        body = [{ "Text" => text }].to_json
+        uri = URI(translate_endpoint)
+        uri.query = URI.encode_www_form(query)
+        response_body = result(uri.to_s, body, default_headers)
+        response_body.first["translations"].first["text"]
+      end
+
       def self.translate_supported?(detected_lang, target_lang)
         SUPPORTED_LANG_MAPPING.keys.include?(detected_lang.to_sym) &&
           SUPPORTED_LANG_MAPPING.values.include?(detected_lang.to_s)

app/services/discourse_translator/provider/yandex.rb

@@ -148,6 +148,11 @@ def self.translate_translatable!(translatable, target_locale_sym = I18n.locale)
         response_body["text"][0]
       end
 
+      def self.translate_text!(translatable, target_locale_sym = I18n.locale)
+        # Not supported for v1.5 https://translate.yandex.com/developers
+        raise TranslatorError.new(I18n.t("translator.not_supported"))
+      end
+
       def self.translate_supported?(detected_lang, target_lang)
         SUPPORTED_LANG_MAPPING.keys.include?(detected_lang.to_sym) &&
           SUPPORTED_LANG_MAPPING.values.include?(detected_lang.to_s)

spec/services/amazon_spec.rb

@@ -46,7 +46,7 @@
     end
   end
 
-  describe ".translate" do
+  describe ".translate_translatable!" do
     let(:post) { Fabricate(:post) }
     let!(:client) { Aws::Translate::Client.new(stub_responses: true) }
 
@@ -66,9 +66,33 @@
     end
 
     it "raises an error when trying to translate an unsupported language" do
-      expect { described_class.translate(post) }.to raise_error(
+      expect { described_class.translate_translatable!(post) }.to raise_error(
         I18n.t("translator.failed.post", source_locale: "en", target_locale: "es"),
       )
     end
   end
+
+  describe ".translate_text!" do
+    let!(:client) { Aws::Translate::Client.new(stub_responses: true) }
+
+    before do
+      client.stub_responses(
+        :translate_text,
+        "UnsupportedLanguagePairException",
+        {
+          translated_text: "Probando traducciones",
+          source_language_code: "en",
+          target_language_code: "es",
+        },
+      )
+      described_class.stubs(:client).returns(client)
+      I18n.stubs(:locale).returns(:es)
+    end
+
+    it "raises an error when trying to translate an unsupported language" do
+      expect { described_class.translate_text!("derp") }.to raise_error(
+        I18n.t("translator.not_supported", source_locale: "en", target_locale: "es"),
+      )
+    end
+  end
 end

spec/services/discourse_ai_spec.rb

@@ -34,7 +34,7 @@
     end
   end
 
-  describe ".translate" do
+  describe ".translate_translatable!" do
     before do
       post.set_detected_locale("de")
       topic.set_detected_locale("de")
@@ -44,8 +44,7 @@
       DiscourseAi::Completions::Llm.with_prepared_responses(
         [translation_json("some translated text")],
       ) do
-        locale, translated_text = DiscourseTranslator::Provider::DiscourseAi.translate(post)
-        expect(locale).to eq "de"
+        translated_text = DiscourseTranslator::Provider::DiscourseAi.translate_translatable!(post)
         expect(translated_text).to eq "<p>some translated text</p>"
       end
     end
@@ -55,8 +54,7 @@
       DiscourseAi::Completions::Llm.with_prepared_responses(
         [translation_json("some translated text")],
       ) do
-        locale, translated_text = DiscourseTranslator::Provider::DiscourseAi.translate(topic)
-        expect(locale).to eq "de"
+        translated_text = DiscourseTranslator::Provider::DiscourseAi.translate_translatable!(topic)
         expect(translated_text).to eq "some translated text"
       end
     end
@@ -73,6 +71,17 @@
     end
   end
 
+  describe ".translate_text!" do
+    it "returns the translated text" do
+      DiscourseAi::Completions::Llm.with_prepared_responses(
+        [translation_json("some translated text")],
+      ) do
+        translated_text = DiscourseTranslator::Provider::DiscourseAi.translate_text!("derp")
+        expect(translated_text).to eq "some translated text"
+      end
+    end
+  end
+
   def locale_json(content)
     { locale: content }.to_json
   end

spec/services/google_spec.rb

@@ -187,4 +187,25 @@
       expect(described_class.translate_translatable!(post)).to eq(translated_text)
     end
   end
+
+  describe ".translate_text!" do
+    it "translates plain text" do
+      text = "ABCDEFG"
+      body = { q: text, target: "ja", key: api_key }
+
+      translated_text = "hur dur hur dur"
+      stub_request(:post, DiscourseTranslator::Provider::Google::TRANSLATE_URI).with(
+        body: URI.encode_www_form(body),
+        headers: {
+          "Content-Type" => "application/x-www-form-urlencoded",
+          "Referer" => "http://test.localhost",
+        },
+      ).to_return(
+        status: 200,
+        body: %{ { "data": { "translations": [ { "translatedText": "#{translated_text}" } ] } } },
+      )
+
+      expect(described_class.translate_text!(text, :ja)).to eq(translated_text)
+    end
+  end
 end