Add embed_url to preview cards (#5775)

app/javascript/mastodon/features/status/components/card.js

@@ -101,7 +101,7 @@ export default class Card extends React.PureComponent {
         onClick={this.handlePhotoClick}
         role='button'
         tabIndex='0'
-        src={card.get('url')}
+        src={card.get('embed_url')}
         alt={card.get('title')}
         width={card.get('width')}
         height={card.get('height')}

app/models/preview_card.rb

@@ -21,6 +21,7 @@
 #  height             :integer          default(0), not null
 #  created_at         :datetime         not null
 #  updated_at         :datetime         not null
+#  embed_url          :string           default(""), not null
 #
 
 class PreviewCard < ApplicationRecord

app/serializers/rest/preview_card_serializer.rb

@@ -6,7 +6,7 @@ class REST::PreviewCardSerializer < ActiveModel::Serializer
   attributes :url, :title, :description, :type,
              :author_name, :author_url, :provider_name,
              :provider_url, :html, :width, :height,
-             :image
+             :image, :embed_url
 
   def image
     object.image? ? full_asset_url(object.image.url(:original)) : nil

app/services/fetch_link_card_service.rb

@@ -74,9 +74,6 @@ class FetchLinkCardService < BaseService
 
     return false unless response.respond_to?(:type)
 
-    # The photo will change the URL. So, to avoid duplication of URLs, PreviewCard needs to be checked again.
-    @card = PreviewCard.find_by(url: response.url) || @card if response.type == 'photo'
-
     @card.type          = response.type
     @card.title         = response.respond_to?(:title)         ? response.title         : ''
     @card.author_name   = response.respond_to?(:author_name)   ? response.author_name   : ''
@@ -90,9 +87,9 @@ class FetchLinkCardService < BaseService
     when 'link'
       @card.image = URI.parse(response.thumbnail_url) if response.respond_to?(:thumbnail_url)
     when 'photo'
-      @card.url    = response.url
-      @card.width  = response.width.presence  || 0
-      @card.height = response.height.presence || 0
+      @card.embed_url = response.url
+      @card.width     = response.width.presence  || 0
+      @card.height    = response.height.presence || 0
     when 'video'
       @card.width  = response.width.presence  || 0
       @card.height = response.height.presence || 0