#399

backend/app/controllers/posts_controller.rb

@@ -114,6 +114,37 @@ class PostsController < ApplicationController
     render json: PostRepr.base(post, current_user)
   end
 
+  def preview
+    return head :unauthorized unless current_user
+    return head :forbidden unless current_user.gte_member?
+    return render_bad_request('URL は必須です．') if params[:url].blank?
+
+    preview = PostImportPreviewer.new.preview_rows(
+        rows: [{
+            source_row: 1,
+            url: params[:url].to_s,
+            attributes: { },
+            provenance: { },
+            tag_sources: { } }],
+        fetch_metadata: true).first
+    return render_validation_error fields: preview[:validation_errors] if preview[:validation_errors].present?
+
+    render json: {
+        url: preview[:url],
+        title: preview[:attributes]['title'],
+        thumbnail_base: preview[:attributes]['thumbnail_base'],
+        tags: preview[:attributes]['tags'],
+        original_created_from: preview[:attributes]['original_created_from'],
+        original_created_before: preview[:attributes]['original_created_before'],
+        duration: preview[:attributes]['duration'],
+        video_ms: preview[:attributes]['video_ms'],
+        field_warnings: preview[:field_warnings],
+        base_warnings: preview[:base_warnings],
+        existing_post: compact_post(preview[:existing_post_id]) }
+  rescue ArgumentError => e
+    render_bad_request e.message
+  end
+
   def show
     post =
         Post
@@ -142,17 +173,21 @@ class PostsController < ApplicationController
     return head :unauthorized unless current_user
     return head :forbidden unless current_user.gte_member?
 
+    if bool?(:dry)
+      preflight = PostCreatePreflight.new(
+          attributes: post_create_attributes,
+          thumbnail: params[:thumbnail]).run
+      return render json: preflight
+    end
+
     post = PostCreator.new(actor: current_user,
-                           attributes: { title: params[:title], url: params[:url],
-                                         thumbnail: params[:thumbnail], tags: params[:tags],
-                                         original_created_from: params[:original_created_from],
-                                         original_created_before: params[:original_created_before],
-                                         parent_post_ids: parse_parent_post_ids,
-                                         video_ms: params[:video_ms],
-                                         duration: params[:duration] }).create!
+                           attributes: post_create_attributes.merge(
+                               thumbnail: params[:thumbnail])).create!
 
     post.reload
     render json: PostRepr.base(post), status: :created
+  rescue PostCreatePreflight::ValidationFailed => e
+    render_validation_error fields: e.fields, base: e.base_errors
   rescue Tag::NicoTagNormalisationError
     render_validation_error fields: { tags: 'ニコニコ・タグは直接指定できません．' }
   rescue Tag::DeprecatedTagNormalisationError
@@ -161,6 +196,8 @@ class PostsController < ApplicationController
     render_validation_error fields: { tags: ['タグ区間の記法が不正です．'] }
   rescue PostCreator::VideoMsParseError
     render_validation_error fields: { video_ms: ['動画時間の記法が不正です．'] }
+  rescue Post::RemoteThumbnailFetchFailed
+    render_validation_error fields: { thumbnail_base: ['サムネイル画像の取得に失敗しました．'] }
   rescue MiniMagick::Error
     render_validation_error fields: { thumbnail: ['サムネイル画像の変換に失敗しました．'] }
   rescue ArgumentError => e
@@ -169,6 +206,22 @@ class PostsController < ApplicationController
     render_post_form_record_invalid e.record
   end
 
+  def bulk
+    return head :unauthorized unless current_user
+    return head :forbidden unless current_user.gte_member?
+    return head :unsupported_media_type unless request.content_mime_type == Mime[:multipart_form]
+
+    result = PostBulkCreator.new(
+        actor: current_user,
+        posts: parse_bulk_posts_manifest,
+        thumbnails: parse_bulk_thumbnails).run
+    render json: result
+  rescue JSON::ParserError
+    render_bad_request 'posts manifest の JSON が不正です．'
+  rescue ArgumentError => e
+    render_validation_error base: [e.message]
+  end
+
   def viewed
     return head :unauthorized unless current_user
 
@@ -463,6 +516,63 @@ class PostsController < ApplicationController
     }.uniq
   end
 
+  def post_create_attributes
+    { title: params[:title],
+      url: params[:url],
+      thumbnail_base: params[:thumbnail_base],
+      tags: params[:tags],
+      original_created_from: params[:original_created_from],
+      original_created_before: params[:original_created_before],
+      parent_post_ids: parse_parent_post_ids,
+      video_ms: params[:video_ms],
+      duration: params[:duration] }
+  end
+
+  def parse_bulk_posts_manifest
+    manifest = params[:posts]
+    raise ArgumentError, 'posts は必須です．' if manifest.blank?
+
+    posts = JSON.parse(manifest)
+    raise ArgumentError, 'posts は配列で指定してください．' unless posts.is_a?(Array)
+    raise ArgumentError, '投稿件数は 1 件以上必要です．' if posts.empty?
+    raise ArgumentError, '投稿件数が多すぎます．' if posts.length > 100
+    raise ArgumentError, 'posts 要素の形式が不正です．' unless posts.all? { _1.is_a?(Hash) }
+
+    posts
+  end
+
+  def parse_bulk_thumbnails
+    thumbnails = { }
+    post_count = Array(JSON.parse(params[:posts].presence || '[]')).length
+
+    params.to_unsafe_h.each do |key, value|
+      match = key.match(/\Athumbnails\[(\d+)\]\z/)
+      next if match.nil?
+
+      index = Integer(match[1], 10)
+      raise ArgumentError, 'thumbnail index が範囲外です．' if index.negative? || index >= post_count
+
+      thumbnails[index] = value
+    end
+
+    thumbnails
+  end
+
+  def compact_post post_id
+    return nil if post_id.blank?
+
+    post = Post.with_attached_thumbnail.find_by(id: post_id)
+    return nil if post.nil?
+
+    { id: post.id,
+      title: post.title,
+      url: post.url,
+      thumbnail_url:
+          if post.thumbnail.attached?
+            rails_storage_proxy_url(post.thumbnail, only_path: false)
+          end }
+  end
+
   def sync_parent_posts! post, parent_post_ids
     if parent_post_ids.include?(post.id)
       post.errors.add :parent_post_ids, '自分自身を親投稿にはできません．'