From 16f435f9313daa9e00dad25e2bcf95e30ad736ed Mon Sep 17 00:00:00 2001
From: George Claghorn <george@basecamp.com>
Date: Wed, 11 Jul 2018 22:09:23 -0400
Subject: [PATCH] Discard ActiveStorage::PurgeJobs for missing blobs

---
 .../app/jobs/active_storage/purge_job.rb      |  2 ++
 activestorage/test/jobs/purge_job_test.rb     | 27 +++++++++++++++++++
 2 files changed, 29 insertions(+)
 create mode 100644 activestorage/test/jobs/purge_job_test.rb

diff --git a/activestorage/app/jobs/active_storage/purge_job.rb b/activestorage/app/jobs/active_storage/purge_job.rb
index 95ae7d0c30..fa15e0451d 100644
--- a/activestorage/app/jobs/active_storage/purge_job.rb
+++ b/activestorage/app/jobs/active_storage/purge_job.rb
@@ -2,6 +2,8 @@
 
 # Provides asynchronous purging of ActiveStorage::Blob records via ActiveStorage::Blob#purge_later.
 class ActiveStorage::PurgeJob < ActiveStorage::BaseJob
+  discard_on ActiveRecord::RecordNotFound
+
   def perform(blob)
     blob.purge
   end
diff --git a/activestorage/test/jobs/purge_job_test.rb b/activestorage/test/jobs/purge_job_test.rb
new file mode 100644
index 0000000000..251022a96f
--- /dev/null
+++ b/activestorage/test/jobs/purge_job_test.rb
@@ -0,0 +1,27 @@
+# frozen_string_literal: true
+
+require "test_helper"
+require "database/setup"
+
+class ActiveStorage::PurgeJobTest < ActiveJob::TestCase
+  setup { @blob = create_blob }
+
+  test "purges" do
+    assert_difference -> { ActiveStorage::Blob.count }, -1 do
+      ActiveStorage::PurgeJob.perform_now @blob
+    end
+
+    assert_not ActiveStorage::Blob.exists?(@blob.id)
+    assert_not ActiveStorage::Blob.service.exist?(@blob.key)
+  end
+
+  test "ignores missing blob" do
+    @blob.purge
+
+    perform_enqueued_jobs do
+      assert_nothing_raised do
+        ActiveStorage::PurgeJob.perform_later @blob
+      end
+    end
+  end
+end