Make domain block/silence/reject-media code more robust (#13424)

* Split media cleanup from reject-media domain blocks to its own service

* Slightly improve ClearDomainMediaService error handling

* Lower DomainClearMediaWorker to lowest-priority queue

* Do not catch ActiveRecord::RecordNotFound in domain block workers

* Fix DomainBlockWorker spec labels

* Add some specs

* Change domain blocks to immediately mark accounts as suspended

Rather than doing so sequentially, account after account, while cleaning
their data. This doesn't change much about the time the block takes to
complete, but it immediately prevents interaction with the blocked domain,
while up to now, it would only be guaranteed when the process ends.

1 files changed, 70 insertions, 0 deletions

diff --git a/app/services/clear_domain_media_service.rb b/app/services/clear_domain_media_service.rb
new file mode 100644
index 000000000..704cfb71a
--- /dev/null
+++ b/app/services/clear_domain_media_service.rb
@@ -0,0 +1,70 @@
+# frozen_string_literal: true
+
+class ClearDomainMediaService < BaseService
+  attr_reader :domain_block
+
+  def call(domain_block)
+    @domain_block = domain_block
+    clear_media! if domain_block.reject_media?
+  end
+
+  private
+
+  def invalidate_association_caches!
+    # Normally, associated models of a status are immutable (except for accounts)
+    # so they are aggressively cached. After updating the media attachments to no
+    # longer point to a local file, we need to clear the cache to make those
+    # changes appear in the API and UI
+    @affected_status_ids.each { |id| Rails.cache.delete_matched("statuses/#{id}-*") }
+  end
+
+  def clear_media!
+    @affected_status_ids = []
+
+    begin
+      clear_account_images!
+      clear_account_attachments!
+      clear_emojos!
+    ensure
+      invalidate_association_caches!
+    end
+  end
+
+  def clear_account_images!
+    blocked_domain_accounts.reorder(nil).find_each do |account|
+      account.avatar.destroy if account.avatar&.exists?
+      account.header.destroy if account.header&.exists?
+      account.save
+    end
+  end
+
+  def clear_account_attachments!
+    media_from_blocked_domain.reorder(nil).find_each do |attachment|
+      @affected_status_ids << attachment.status_id if attachment.status_id.present?
+
+      attachment.file.destroy if attachment.file&.exists?
+      attachment.type = :unknown
+      attachment.save
+    end
+  end
+
+  def clear_emojos!
+    emojis_from_blocked_domains.destroy_all
+  end
+
+  def blocked_domain
+    domain_block.domain
+  end
+
+  def blocked_domain_accounts
+    Account.by_domain_and_subdomains(blocked_domain)
+  end
+
+  def media_from_blocked_domain
+    MediaAttachment.joins(:account).merge(blocked_domain_accounts).reorder(nil)
+  end
+
+  def emojis_from_blocked_domains
+    CustomEmoji.by_domain_and_subdomains(blocked_domain)
+  end
+end