From 67ee638c28ed8119b02ae0675d04e3a63e16a75c Mon Sep 17 00:00:00 2001
From: Eugen Rochko <eugen@zeonfederated.com>
Date: Mon, 15 Jan 2018 04:34:28 +0100
Subject: [PATCH] Move e-mail digest task to sidekiq, reduce workload, improve
 hint (#6252)

---
 app/models/user.rb                       |  4 ++++
 app/workers/digest_mailer_worker.rb      |  6 +-----
 app/workers/scheduler/email_scheduler.rb | 24 ++++++++++++++++++++++++
 config/locales/simple_form.en.yml        |  2 +-
 config/sidekiq.yml                       |  3 +++
 lib/tasks/mastodon.rake                  |  7 +++----
 6 files changed, 36 insertions(+), 10 deletions(-)
 create mode 100644 app/workers/scheduler/email_scheduler.rb

diff --git a/app/models/user.rb b/app/models/user.rb
index 9459db7fe4..892a07bba0 100644
--- a/app/models/user.rb
+++ b/app/models/user.rb
@@ -170,6 +170,10 @@ class User < ApplicationRecord
     settings.default_privacy || (account.locked? ? 'private' : 'public')
   end
 
+  def allows_digest_emails?
+    settings.notification_emails['digest']
+  end
+
   def token_for_app(a)
     return nil if a.nil? || a.owner != self
     Doorkeeper::AccessToken
diff --git a/app/workers/digest_mailer_worker.rb b/app/workers/digest_mailer_worker.rb
index 028db89a9a..21f1c357a0 100644
--- a/app/workers/digest_mailer_worker.rb
+++ b/app/workers/digest_mailer_worker.rb
@@ -9,7 +9,7 @@ class DigestMailerWorker
 
   def perform(user_id)
     @user = User.find(user_id)
-    deliver_digest if user_receives_digest?
+    deliver_digest if @user.allows_digest_emails?
   end
 
   private
@@ -18,8 +18,4 @@ class DigestMailerWorker
     NotificationMailer.digest(user.account).deliver_now!
     user.touch(:last_emailed_at)
   end
-
-  def user_receives_digest?
-    user.settings.notification_emails['digest']
-  end
 end
diff --git a/app/workers/scheduler/email_scheduler.rb b/app/workers/scheduler/email_scheduler.rb
new file mode 100644
index 0000000000..24d0c0ebef
--- /dev/null
+++ b/app/workers/scheduler/email_scheduler.rb
@@ -0,0 +1,24 @@
+# frozen_string_literal: true
+require 'sidekiq-scheduler'
+
+class Scheduler::EmailScheduler
+  include Sidekiq::Worker
+
+  def perform
+    eligible_users.find_each do |user|
+      next unless user.allows_digest_emails?
+      DigestMailerWorker.perform_async(user.id)
+    end
+  end
+
+  private
+
+  def eligible_users
+    User.confirmed
+        .joins(:account)
+        .where(accounts: { silenced: false, suspended: false })
+        .where(disabled: false)
+        .where('current_sign_in_at < ?', 20.days.ago)
+        .where('last_emailed_at IS NULL OR last_emailed_at < ?', 20.days.ago)
+  end
+end
diff --git a/config/locales/simple_form.en.yml b/config/locales/simple_form.en.yml
index ff1a40ccd0..143daaa298 100644
--- a/config/locales/simple_form.en.yml
+++ b/config/locales/simple_form.en.yml
@@ -4,7 +4,7 @@ en:
     hints:
       defaults:
         avatar: PNG, GIF or JPG. At most 2MB. Will be downscaled to 120x120px
-        digest: Sent after a long period of inactivity with a summary of mentions you've received in your absence
+        digest: Only sent after a long period of inactivity and only if you have received any personal messages in your absence
         display_name:
           one: <span class="name-counter">1</span> character left
           other: <span class="name-counter">%{count}</span> characters left
diff --git a/config/sidekiq.yml b/config/sidekiq.yml
index 4c35dcd43a..bfe29b8f81 100644
--- a/config/sidekiq.yml
+++ b/config/sidekiq.yml
@@ -27,3 +27,6 @@
   ip_cleanup_scheduler:
     cron: '<%= Random.rand(0..59) %> <%= Random.rand(3..5) %> * * *'
     class: Scheduler::IpCleanupScheduler
+  email_scheduler:
+    cron: '0 10 * * 2'
+    class: Scheduler::EmailScheduler
diff --git a/lib/tasks/mastodon.rake b/lib/tasks/mastodon.rake
index 33969d470c..38dbed982a 100644
--- a/lib/tasks/mastodon.rake
+++ b/lib/tasks/mastodon.rake
@@ -171,11 +171,10 @@ namespace :mastodon do
   end
 
   namespace :emails do
-    desc 'Send out digest e-mails'
+    desc 'Send out digest e-mails (deprecated)'
     task digest: :environment do
-      User.confirmed.joins(:account).where(accounts: { silenced: false, suspended: false }).where('current_sign_in_at < ?', 20.days.ago).find_each do |user|
-        DigestMailerWorker.perform_async(user.id)
-      end
+      # No-op
+      # This task is now executed via sidekiq-scheduler
     end
   end