#422

backend/app/controllers/tag_descriptions_controller.rb

@@ -0,0 +1,74 @@
+class TagDescriptionsController < ApplicationController
+  def show
+    description = TagDescription.find_by(tag_id: params[:id], language_code: 'ja')
+    return head :not_found unless description
+
+    render json: representation(description)
+  end
+
+  def show_by_title
+    tag_name = TagName.find_by(language_code: 'ja', name: params[:name].to_s.strip)
+    description = tag_name&.tag && TagDescription.find_by(tag: tag_name.tag, language_code: 'ja')
+    return head :not_found unless description
+
+    render json: representation(description)
+  end
+
+  def create
+    return head :unauthorized unless current_user
+    return head :forbidden unless current_user.gte_member?
+
+    body = params[:body].to_s
+    return render_unprocessable_entity('本文は必須です．', field: :body) if body.blank?
+
+    tag = Tag.find_by(id: params[:id])
+    return head :not_found unless tag
+
+    if TagDescription.exists?(tag:, language_code: 'ja')
+      return render_unprocessable_entity('説明はすでに存在します．')
+    end
+
+    TagDescriptionOperation.create!(tag:, body:, created_by_user: current_user)
+    description = TagDescription.find_by!(tag:, language_code: 'ja')
+
+    render json: representation(description), status: :created
+  rescue ActiveRecord::RecordInvalid => e
+    render_validation_error e.record
+  rescue ActiveRecord::RecordNotUnique
+    render_record_not_unique
+  end
+
+  def update
+    return head :unauthorized unless current_user
+    return head :forbidden unless current_user.gte_member?
+
+    body = params[:body].to_s
+    return render_unprocessable_entity('本文は必須です．', field: :body) if body.blank?
+
+    description = TagDescription.find_by(tag_id: params[:id], language_code: 'ja')
+    return head :not_found unless description
+
+    page = WikiPage.find(description.id)
+    TagDescriptionOperation.update!(
+        description:, page:, body:, updated_by_user: current_user)
+    description.reload
+
+    render json: representation(description)
+  rescue ActiveRecord::RecordInvalid => e
+    render_validation_error e.record
+  end
+
+  private
+
+  def representation description
+    description.as_json(only: [
+        :tag_id,
+        :language_code,
+        :body,
+        :version_no,
+        :created_by_user_id,
+        :updated_by_user_id,
+        :created_at,
+        :updated_at])
+  end
+end

backend/app/services/tag_description_operation.rb

@@ -0,0 +1,51 @@
+class TagDescriptionOperation
+  LANGUAGE_CODE = 'ja'
+
+  def self.create!(tag:, body:, created_by_user:, message: nil)
+    ApplicationRecord.transaction do
+      tag.lock!
+      raise ActiveRecord::RecordNotUnique if TagDescription.exists?(
+          tag_id: tag.id, language_code: LANGUAGE_CODE)
+
+      page = Wiki::Commit.create_legacy_content!(
+          tag_name: tag.tag_name(LANGUAGE_CODE), body:, created_by_user:, message:)
+      revision = page.wiki_revisions.order(id: :desc).first
+      record_version!(tag:, revision:, body:, user: created_by_user,
+                      description: nil)
+      page
+    end
+  end
+
+  def self.update!(description:, page:, body:, updated_by_user:, message: nil,
+                   base_revision_id: nil)
+    ApplicationRecord.transaction do
+      description&.lock!
+      page.lock!
+      revision = Wiki::Commit.legacy_content!(
+          page:, body:, created_user: updated_by_user, message:,
+          base_revision_id:)
+      record_version!(tag: page.tag_name.tag, revision:, body: revision.body,
+                      user: updated_by_user, description:)
+      description || TagDescription.find_by!(
+          tag_id: page.tag_name.tag_id, language_code: LANGUAGE_CODE)
+    end
+  end
+
+  def self.record_version! tag:, revision:, body:, user:, description:
+    version_no = description ? description.version_no + 1 : 1
+    TagDescriptionVersion.create!(
+        id: revision.id, tag_id: tag.id, language_code: LANGUAGE_CODE,
+        version_no:, event_type: description ? 'update' : 'create', body:,
+        created_by_user_id: user.id, created_at: revision.created_at)
+    if description
+      description.update!(body:, version_no:, updated_by_user_id: user.id)
+    else
+      TagDescription.create!(
+          id: revision.wiki_page_id, tag_id: tag.id,
+          language_code: LANGUAGE_CODE, version_no:, body:,
+          created_by_user_id: user.id, updated_by_user_id: user.id)
+    end
+  end
+
+  private_class_method :record_version!
+end

backend/app/services/wiki/commit.rb

@@ -8,6 +8,15 @@ module Wiki
     end
 
     def self.create_content! tag_name:, body:, created_by_user:, message: nil
+      if tag_name.tag && tag_name.language_code == 'ja'
+        return TagDescriptionOperation.create!(
+            tag: tag_name.tag, body:, created_by_user:, message:)
+      end
+
+      create_legacy_content!(tag_name:, body:, created_by_user:, message:)
+    end
+
+    def self.create_legacy_content! tag_name:, body:, created_by_user:, message: nil
       normalised = normalise_body(body)
 
       page = WikiPage.new(tag_name:,
@@ -33,6 +42,20 @@ module Wiki
     end
 
     def self.content! page:, body:, created_user:, message: nil, base_revision_id: nil
+      tag = page.tag_name.tag
+      description = tag && page.tag_name.language_code == 'ja' &&
+          TagDescription.find_by(tag_id: tag.id, language_code: 'ja')
+      if tag && page.tag_name.language_code == 'ja'
+        return TagDescriptionOperation.update!(
+            description:, page:, body:, updated_by_user: created_user,
+            message:, base_revision_id:)
+      end
+
+      legacy_content!(page:, body:, created_user:, message:, base_revision_id:)
+    end
+
+    def self.legacy_content! page:, body:, created_user:, message: nil,
+                             base_revision_id: nil
       new(page:, created_user:).content!(body:, message:, base_revision_id:)
     end
 
@@ -93,8 +116,6 @@ module Wiki
           { wiki_revision_id: rev.id, wiki_line_id: line_id, position: pos }
         end
         WikiRevisionLine.insert_all!(rows) if rows.any?
-        record_description!(rev, normalised)
-
         rev
       end
     end
@@ -110,26 +131,6 @@ module Wiki
 
     private
 
-    def record_description! revision, body
-      tag = @page.tag_name.tag
-      return unless tag && @page.tag_name.language_code == 'ja'
-
-      tag.lock!
-      description = TagDescription.lock.find_by(tag_id: tag.id, language_code: 'ja')
-      version_no = description ? description.version_no + 1 : 1
-      TagDescriptionVersion.create!(
-          id: revision.id, tag_id: tag.id, language_code: 'ja', version_no:,
-          event_type: description ? 'update' : 'create', body:,
-          created_by_user_id: @created_user.id, created_at: revision.created_at)
-      if description
-        description.update!(body:, version_no:, updated_by_user_id: @created_user.id)
-      else
-        TagDescription.create!(
-            id: @page.id, tag_id: tag.id, language_code: 'ja', version_no:, body:,
-            created_by_user_id: @created_user.id, updated_by_user_id: @created_user.id)
-      end
-    end
-
     def split_lines(body) = body.split("\n")
 
     def upsert_lines! lines, line_shas

backend/config/routes.rb

@@ -1,4 +1,12 @@
 Rails.application.routes.draw do
+  get 'tags/name/:name/description', to: 'tag_descriptions#show_by_title'
+
+  scope 'tags/:id/description', controller: :tag_descriptions do
+    get '', action: :show
+    post '', action: :create
+    put '', action: :update
+  end
+
   resources :nico_tags, path: 'tags/nico', only: [:index, :show, :update]
 
   scope 'tags/:parent_id/children', controller: :tag_children do