From 5dadb6896ba621ff499b365f9b39411ff482846c Mon Sep 17 00:00:00 2001
From: Akihiko Odaki <akihiko.odaki.4i@stu.hosei.ac.jp>
Date: Wed, 16 May 2018 19:29:45 +0900
Subject: [PATCH] Raise Mastodon::RaceConditionError if Redis lock failed
 (#7511)

An explicit error allows user agents to know the error and Sidekiq to
retry.
---
 app/controllers/media_proxy_controller.rb           | 2 ++
 app/lib/activitypub/activity/create.rb              | 2 ++
 app/lib/ostatus/activity/creation.rb                | 2 ++
 app/services/activitypub/process_account_service.rb | 2 ++
 app/services/fetch_link_card_service.rb             | 2 ++
 app/services/resolve_account_service.rb             | 2 ++
 6 files changed, 12 insertions(+)

diff --git a/app/controllers/media_proxy_controller.rb b/app/controllers/media_proxy_controller.rb
index 155670837e..d820b257e0 100644
--- a/app/controllers/media_proxy_controller.rb
+++ b/app/controllers/media_proxy_controller.rb
@@ -8,6 +8,8 @@ class MediaProxyController < ApplicationController
       if lock.acquired?
         @media_attachment = MediaAttachment.remote.find(params[:id])
         redownload! if @media_attachment.needs_redownload? && !reject_media?
+      else
+        raise Mastodon::RaceConditionError
       end
     end
 
diff --git a/app/lib/activitypub/activity/create.rb b/app/lib/activitypub/activity/create.rb
index 8d17a4ebe2..ab1d63cd49 100644
--- a/app/lib/activitypub/activity/create.rb
+++ b/app/lib/activitypub/activity/create.rb
@@ -11,6 +11,8 @@ class ActivityPub::Activity::Create < ActivityPub::Activity
       if lock.acquired?
         @status = find_existing_status
         process_status if @status.nil?
+      else
+        raise Mastodon::RaceConditionError
       end
     end
 
diff --git a/app/lib/ostatus/activity/creation.rb b/app/lib/ostatus/activity/creation.rb
index dbccc83302..d3a303a0c4 100644
--- a/app/lib/ostatus/activity/creation.rb
+++ b/app/lib/ostatus/activity/creation.rb
@@ -15,6 +15,8 @@ class OStatus::Activity::Creation < OStatus::Activity::Base
         @status = find_status(id)
         return [@status, false] unless @status.nil?
         @status = process_status
+      else
+        raise Mastodon::RaceConditionError
       end
     end
 
diff --git a/app/services/activitypub/process_account_service.rb b/app/services/activitypub/process_account_service.rb
index 783bbd8e57..453253db40 100644
--- a/app/services/activitypub/process_account_service.rb
+++ b/app/services/activitypub/process_account_service.rb
@@ -23,6 +23,8 @@ class ActivityPub::ProcessAccountService < BaseService
         create_account if @account.nil?
         update_account
         process_tags
+      else
+        raise Mastodon::RaceConditionError
       end
     end
 
diff --git a/app/services/fetch_link_card_service.rb b/app/services/fetch_link_card_service.rb
index f9b1b2f0c6..86d0f9971d 100644
--- a/app/services/fetch_link_card_service.rb
+++ b/app/services/fetch_link_card_service.rb
@@ -23,6 +23,8 @@ class FetchLinkCardService < BaseService
       if lock.acquired?
         @card = PreviewCard.find_by(url: @url)
         process_url if @card.nil? || @card.updated_at <= 2.weeks.ago
+      else
+        raise Mastodon::RaceConditionError
       end
     end
 
diff --git a/app/services/resolve_account_service.rb b/app/services/resolve_account_service.rb
index de8d1151d3..4323e7f06d 100644
--- a/app/services/resolve_account_service.rb
+++ b/app/services/resolve_account_service.rb
@@ -49,6 +49,8 @@ class ResolveAccountService < BaseService
         else
           handle_ostatus
         end
+      else
+        raise Mastodon::RaceConditionError
       end
     end