#399

backend/app/controllers/post_imports_controller.rb

@@ -11,7 +11,12 @@ class PostImportsController < ApplicationController
 
   def validate
     rows = normalised_import_rows allow_warning_fields: true
-    changed_row = Integer(params[:changed_row], exception: false)
+    changed_row =
+        if params[:changed_row].to_s == 'all'
+          true
+        else
+          Integer(params[:changed_row], exception: false)
+        end
     result =
         PostImportPreviewer.new.preview_rows(rows:,
                                              fetch_metadata: changed_row,

backend/app/controllers/preview_controller.rb

@@ -38,6 +38,27 @@ class PreviewController < ApplicationController
     render_unprocessable_entity(e.message)
   end
 
+  def image
+    return render_bad_request('URL は必須です．') if params[:url].blank?
+
+    attachment = Post.resized_thumbnail_attachment(
+        StringIO.new(Preview::ThumbnailFetcher.fetch_image_response(params[:url]).body))
+    attachment[:io].rewind
+    send_data attachment[:io].read,
+              type: attachment[:content_type],
+              disposition: 'inline'
+  rescue Preview::UrlSafety::UnsafeUrl => e
+    render_bad_request(e.message)
+  rescue Preview::HttpFetcher::FetchTimeout => e
+    render_preview_error(e.message, :gateway_timeout)
+  rescue Preview::HttpFetcher::ResponseTooLarge => e
+    render_preview_error(e.message, :payload_too_large)
+  rescue Preview::HttpFetcher::FetchFailed => e
+    render_preview_error(e.message, :bad_gateway)
+  rescue Preview::ThumbnailFetcher::GenerationFailed, MiniMagick::Error => e
+    render_unprocessable_entity(e.message)
+  end
+
   private
 
   def require_member!

backend/config/routes.rb

@@ -31,6 +31,7 @@ Rails.application.routes.draw do
   scope :preview, controller: :preview do
     get :title
     get :thumbnail
+    get :image
   end
 
   scope 'posts/import', controller: :post_imports do