From 75a2c7f83314c5e643ca81f39fffc748aa792217 Mon Sep 17 00:00:00 2001
From: Felipe Sateler <fsateler@gmail.com>
Date: Thu, 20 Apr 2023 12:35:17 -0400
Subject: [PATCH] Don't fail lock release if the connection was disconnected

If the connection is broken, then the lock was released because
the session is aborted. Thus there is no need to fail.
---
 lib/with_advisory_lock/postgresql.rb | 2 ++
 test/lock_test.rb                    | 6 ++++++
 test/test_helper.rb                  | 1 +
 3 files changed, 9 insertions(+)

diff --git a/lib/with_advisory_lock/postgresql.rb b/lib/with_advisory_lock/postgresql.rb
index ae369cb..e5c8065 100644
--- a/lib/with_advisory_lock/postgresql.rb
+++ b/lib/with_advisory_lock/postgresql.rb
@@ -14,6 +14,8 @@ def release_lock
       pg_function = "pg_advisory_unlock#{shared ? '_shared' : ''}"
       execute_successful?(pg_function)
     rescue ActiveRecord::StatementInvalid => e
+      # If something goes real bad, pg will close the connection. in that case the lock is no longer held
+      return if e.message =~ /PG::ConnectionBad:/
       raise unless e.message =~ / ERROR: +current transaction is aborted,/
 
       begin
diff --git a/test/lock_test.rb b/test/lock_test.rb
index 1a6e583..1d22da1 100644
--- a/test/lock_test.rb
+++ b/test/lock_test.rb
@@ -56,6 +56,12 @@
 
       thread_with_lock.kill
     end
+
+    it 'handles lost connection gracefully' do
+      Tag.with_advisory_lock(lock_name) { Tag.connection.disconnect! }
+
+      assert_nil(Tag.current_advisory_lock)
+    end
   end
 
   describe '.with_advisory_lock!' do
diff --git a/test/test_helper.rb b/test/test_helper.rb
index f28bb1b..50034b6 100644
--- a/test/test_helper.rb
+++ b/test/test_helper.rb
@@ -37,6 +37,7 @@ def env_db
 module MiniTest
   class Spec
     before do
+      ActiveRecord::Base.establish_connection
       ENV['FLOCK_DIR'] = Dir.mktmpdir
       Tag.delete_all
       TagAudit.delete_all