FEATURE: Experimental feature for viewing translated topics

assets/javascripts/discourse/components/show-original-content.gjs

@@ -0,0 +1,46 @@
+import Component from "@glimmer/component";
+import { tracked } from "@glimmer/tracking";
+import { action } from "@ember/object";
+import { service } from "@ember/service";
+import DButton from "discourse/components/d-button";
+import concatClass from "discourse/helpers/concat-class";
+
+export default class ShowOriginalContent extends Component {
+  @service router;
+  @tracked isTranslated = true;
+
+  constructor() {
+    super(...arguments);
+    this.isTranslated = !new URLSearchParams(window.location.search).has(
+      "show"
+    );
+  }
+
+  @action
+  async showOriginal() {
+    const params = new URLSearchParams(window.location.search);
+    if (this.isTranslated) {
+      params.append("show", "original");
+    } else {
+      params.delete("show");
+    }
+    window.location.search = params.toString();
+  }
+
+  get title() {
+    return this.isTranslated
+      ? "translator.content_translated"
+      : "translator.content_not_translated";
+  }
+
+  <template>
+    <div class="discourse-translator_toggle-original">
+      <DButton
+        @icon="language"
+        @title={{this.title}}
+        class={{concatClass "btn btn-default" (if this.isTranslated "active")}}
+        @action={{this.showOriginal}}
+      />
+    </div>
+  </template>
+}

assets/javascripts/discourse/initializers/extend-for-translate-button.js

@@ -5,6 +5,7 @@ import { withPluginApi } from "discourse/lib/plugin-api";
 import { i18n } from "discourse-i18n";
 import LanguageSwitcher from "../components/language-switcher";
 import ToggleTranslationButton from "../components/post-menu/toggle-translation-button";
+import ShowOriginalContent from "../components/show-original-content";
 import TranslatedPost from "../components/translated-post";
 
 function initializeTranslation(api) {
@@ -23,7 +24,33 @@ function initializeTranslation(api) {
     );
   }
 
-  if (currentUser) {
+  if (
+    siteSettings.experimental_topic_translation &&
+    (currentUser || siteSettings.experimental_anon_language_switcher)
+  ) {
+    api.renderInOutlet("topic-navigation", ShowOriginalContent);
+    api.decorateCookedElement((cookedElement, helper) => {
+      if (helper) {
+        const translatedCooked = helper.getModel().get("translated_cooked");
+        if (translatedCooked) {
+          cookedElement.innerHTML = translatedCooked;
+        } else {
+          // this experimental feature does not yet support
+          // translating individual untranslated posts
+        }
+      }
+    });
+
+    api.registerModelTransformer("topic", (topics) => {
+      topics.forEach((topic) => {
+        if (topic.translated_title) {
+          topic.set("fancy_title", topic.translated_title);
+        }
+      });
+    });
+  }
+
+  if (!siteSettings.experimental_topic_translation) {
     customizePostMenu(api);
   }
 }

assets/stylesheets/common/common.scss

@@ -2,3 +2,19 @@
   .fk-d-menu__inner-content {
   max-height: 50vh;
 }
+
+.topic-navigation.with-timeline .discourse-translator_toggle-original {
+  margin-bottom: 0.5em;
+}
+
+.topic-navigation.with-topic-progress
+  .discourse-translator_toggle-original
+  button {
+  height: 100%;
+}
+
+.discourse-translator_toggle-original {
+  button.active svg {
+    color: var(--tertiary);
+  }
+}

config/locales/client.en.yml

@@ -6,7 +6,7 @@ en:
           discourse_translator: "Discourse Translator"
   js:
     translator:
-      view_translation: "View translation"
-      hide_translation: "Hide translation"
+      content_not_translated: "Content not translated. Click to translate"
+      content_translated: "Content is translated. Click to view original"
       translated_from: "Translated from %{language} by %{translator}"
       translating: "Translating"

config/locales/server.en.yml

@@ -20,6 +20,7 @@ en:
     experimental_anon_language_switcher: "Enable experimental language switcher for anonymous users. This will allow anonymous users to switch between translated versions of Discourse and user-contributed content in topics."
     errors:
       set_locale_cookie_requirements: "The experimental language switcher for anonymous users requires the `set locale from cookie` site setting to be enabled."
+    experimental_topic_translation: "Enable experimental topic translation feature. This replaces existing post in-line translation with a button that allows users to translate the entire topic."
   translator:
     failed: "The translator is unable to translate this content (%{source_locale}) to the default language of this site (%{target_locale})."
     not_supported: "This language is not supported by the translator."

config/settings.yml

@@ -106,3 +106,6 @@ discourse_translator:
     default: false
     client: true
     validator: "LanguageSwitcherSettingValidator"
+  experimental_topic_translation:
+    default: false
+    client: true

plugin.rb

@@ -41,4 +41,18 @@ module ::DiscourseTranslator
   add_to_serializer :post, :can_translate do
     scope.can_translate?(object)
   end
+
+  add_to_serializer :post, :translated_cooked do
+    if !SiteSetting.experimental_topic_translation || scope.request.params["show"] == "original"
+      return nil
+    end
+    object.translation_for(I18n.locale) || nil
+  end
+
+  add_to_serializer :topic_view, :translated_title do
+    if !SiteSetting.experimental_topic_translation || scope.request.params["show"] == "original"
+      return nil
+    end
+    object.topic.translation_for(I18n.locale) || nil
+  end
 end

spec/serializers/post_serializer_spec.rb

@@ -79,4 +79,40 @@
       end
     end
   end
+
+  describe "#cooked" do
+    def serialize_post(guardian_user: user, params: {})
+      env = { "action_dispatch.request.parameters" => params, "REQUEST_METHOD" => "GET" }
+      request = ActionDispatch::Request.new(env)
+      guardian = Guardian.new(guardian_user, request)
+      PostSerializer.new(post, scope: guardian)
+    end
+
+    before { SiteSetting.experimental_topic_translation = true }
+
+    it "does not return translated_cooked when experimental_topic_translation is disabled" do
+      SiteSetting.experimental_topic_translation = false
+      expect(serialize_post.translated_cooked).to eq(nil)
+    end
+
+    it "does not return translated_cooked when show=original param is present" do
+      I18n.locale = "ja"
+      post.set_translation("ja", "こんにちは")
+
+      expect(serialize_post(params: { "show" => "original" }).translated_cooked).to eq(nil)
+      expect(serialize_post(params: { "show" => "derp" }).translated_cooked).to eq("こんにちは")
+    end
+
+    it "returns translated content based on locale" do
+      I18n.locale = "ja"
+      post.set_translation("ja", "こんにちは")
+      post.set_translation("es", "Hola")
+      expect(serialize_post.translated_cooked).to eq("こんにちは")
+    end
+
+    it "does not return translated_cooked when plugin is disabled" do
+      SiteSetting.translator_enabled = false
+      expect(serialize_post.translated_cooked).to eq(nil)
+    end
+  end
 end

spec/serializers/topic_view_serializer_spec.rb

@@ -30,4 +30,47 @@
 
     expect(topic_view.posts.first.association(:content_locale)).to be_loaded
   end
+
+  describe "#translated_title" do
+    fab!(:user) { Fabricate(:user, locale: "ja") }
+    fab!(:topic)
+
+    let!(:guardian) { Guardian.new(user) }
+    let!(:original_title) { "FUS ROH DAAHHH" }
+    let!(:jap_title) { "フス・ロ・ダ・ア" }
+
+    before do
+      topic.title = original_title
+      SiteSetting.experimental_topic_translation = true
+      I18n.locale = "ja"
+    end
+
+    def serialize_topic(guardian_user: user, params: {})
+      env = { "action_dispatch.request.parameters" => params, "REQUEST_METHOD" => "GET" }
+      request = ActionDispatch::Request.new(env)
+      guardian = Guardian.new(guardian_user, request)
+      TopicViewSerializer.new(TopicView.new(topic), scope: guardian)
+    end
+
+    it "does not return translated_title when experimental_topic_translation is disabled" do
+      SiteSetting.experimental_topic_translation = false
+      topic.set_translation("ja", jap_title)
+
+      expect(serialize_topic.translated_title).to eq(nil)
+    end
+
+    it "does not return translated_title when show_original param is present" do
+      topic.set_translation("ja", jap_title)
+      expect(serialize_topic(params: { "show" => "original" }).translated_title).to eq(nil)
+    end
+
+    it "does not return translated_title when no translation exists" do
+      expect(serialize_topic.translated_title).to eq(nil)
+    end
+
+    it "returns translated title when translation exists for current locale" do
+      topic.set_translation("ja", jap_title)
+      expect(serialize_topic.translated_title).to eq(jap_title)
+    end
+  end
 end

spec/system/full_page_translation_spec.rb

@@ -0,0 +1,57 @@
+# frozen_string_literal: true
+
+RSpec.describe "Full page translation", type: :system do
+  fab!(:japanese_user) { Fabricate(:user, locale: "ja") }
+  fab!(:site_local_user) { Fabricate(:user, locale: "en") }
+  fab!(:author) { Fabricate(:user) }
+
+  fab!(:topic) { Fabricate(:topic, title: "Life strategies from The Art of War", user: author) }
+  fab!(:post_1) do
+    Fabricate(:post, topic: topic, raw: "The masterpiece isn’t just about military strategy")
+  end
+  fab!(:post_2) do
+    Fabricate(:post, topic: topic, raw: "The greatest victory is that which requires no battle")
+  end
+
+  let(:topic_page) { PageObjects::Pages::Topic.new }
+
+  before do
+    # topic translation setup
+    topic.set_detected_locale("en")
+    post_1.set_detected_locale("en")
+    post_2.set_detected_locale("en")
+
+    topic.set_translation("ja", "孫子兵法からの人生戦略")
+    topic.set_translation("es", "Estrategias de vida de El arte de la guerra")
+    post_1.set_translation("ja", "傑作は単なる軍事戦略についてではありません")
+    post_2.set_translation("ja", "最大の勝利は戦いを必要としないものです")
+  end
+
+  context "when the feature is enabled" do
+    before do
+      SiteSetting.translator_enabled = true
+      SiteSetting.allow_user_locale = true
+      SiteSetting.set_locale_from_cookie = true
+      SiteSetting.set_locale_from_param = true
+      SiteSetting.experimental_anon_language_switcher = true
+      SiteSetting.experimental_topic_translation = true
+    end
+
+    it "shows the correct language based on the selected language and login status" do
+      visit("/t/#{topic.slug}/#{topic.id}?lang=ja")
+      expect(topic_page.has_topic_title?("孫子兵法からの人生戦略")).to eq(true)
+      expect(find(topic_page.post_by_number_selector(1))).to have_content("傑作は単なる軍事戦略についてではありません")
+
+      visit("/t/#{topic.id}")
+      expect(topic_page.has_topic_title?("Life strategies from The Art of War")).to eq(true)
+      expect(find(topic_page.post_by_number_selector(1))).to have_content(
+        "The masterpiece isn’t just about military strategy",
+      )
+
+      sign_in(japanese_user)
+      visit("/")
+      visit("/t/#{topic.id}")
+      expect(topic_page.has_topic_title?("孫子兵法からの人生戦略")).to eq(true)
+    end
+  end
+end