Fix mastodon#1813 - Alleviate extra requests when processing mentions (…

…mastodon#1938)

The <link rel="mentioned" /> tag refers to accounts by href. So we were
matching the DB by the url attribute, and falling back to HTTP look-up.
However, GS and Mastodon use profile URLs as URIs, too, and the match
for that was missing. This could potentially alleviate some extra network
requests

app/services/process_feed_service.rb

@@ -161,13 +161,7 @@ def mentions_from_xml(parent, xml)
  xml.xpath('./xmlns:link[@rel="mentioned"]', xmlns: TagManager::XMLNS).each do |link|
  next if [TagManager::TYPES[:group], TagManager::TYPES[:collection]].include? link['ostatus:object-type']
 
- url = Addressable::URI.parse(link['href'])
-
- mentioned_account = if TagManager.instance.web_domain?(url.host)
- Account.find_local(url.path.gsub('/users/', ''))
- else
- Account.find_by(url: link['href']) || FetchRemoteAccountService.new.call(link['href'])
- end
+ mentioned_account = account_from_href(link['href'])
 
  next if mentioned_account.nil? || processed_account_ids.include?(mentioned_account.id)
 
@@ -178,6 +172,16 @@ def mentions_from_xml(parent, xml)
  end
  end
 
+ def account_from_href(href)
+ url = Addressable::URI.parse(href)
+
+ if TagManager.instance.web_domain?(url.host)
+ Account.find_local(url.path.gsub('/users/', ''))
+ else
+ Account.find_by(uri: href) || Account.find_by(url: href) || FetchRemoteAccountService.new.call(href)
+ end
+ end
+
  def hashtags_from_xml(parent, xml)
  tags = xml.xpath('./xmlns:category', xmlns: TagManager::XMLNS).map { |category| category['term'] }.select(&:present?)
  ProcessHashtagsService.new.call(parent, tags)