feat: add optional clearing of ActiveRecord connections after each job

Author: rafael-pissardo

lib/solid_queue.rb

@@ -40,6 +40,7 @@ module SolidQueue
   mattr_accessor :preserve_finished_jobs, default: true
   mattr_accessor :clear_finished_jobs_after, default: 1.day
   mattr_accessor :default_concurrency_control_period, default: 3.minutes
+  mattr_accessor :clear_connections_after_job, default: false
 
   delegate :on_start, :on_stop, :on_exit, to: Supervisor
 

lib/solid_queue/pool.rb

@@ -1,5 +1,7 @@
 # frozen_string_literal: true
 
+require "active_record"
+
 module SolidQueue
   class Pool
     include AppExecutor
@@ -22,6 +24,7 @@ def post(execution)
         wrap_in_app_executor do
           thread_execution.perform
         ensure
+          ActiveRecord::Base.clear_active_connections! if SolidQueue.clear_connections_after_job
           available_threads.increment
           mutex.synchronize { on_idle.try(:call) if idle? }
         end

test/unit/pool_connection_clear_test.rb

@@ -0,0 +1,27 @@
+require "test_helper"
+require "active_support/testing/method_call_assertions"
+
+class PoolConnectionClearTest < ActiveSupport::TestCase
+  include ActiveSupport::Testing::MethodCallAssertions
+  include JobsTestHelper
+
+  self.use_transactional_tests = false
+
+  test "clears ActiveRecord connections after executing a job" do
+    old_flag, SolidQueue.clear_connections_after_job = SolidQueue.clear_connections_after_job, true
+    # Enqueue a simple job
+    AddToBufferJob.perform_later "memory check"
+
+    # Expect ActiveRecord connections to be cleared at least once during job processing
+    ActiveRecord::Base.expects(:clear_active_connections!).at_least_once
+
+    worker = SolidQueue::Worker.new(queues: "background", threads: 1, polling_interval: 0.1)
+    worker.start
+
+    # Wait for the job to finish and stop the worker
+    wait_for_jobs_to_finish_for(2.seconds)
+    worker.stop
+  ensure
+    SolidQueue.clear_connections_after_job = old_flag
+  end
+end

test/unit/pool_connection_clear_toggle_test.rb

@@ -0,0 +1,25 @@
+require "test_helper"
+require "active_support/testing/method_call_assertions"
+
+class PoolConnectionClearToggleTest < ActiveSupport::TestCase
+  include ActiveSupport::Testing::MethodCallAssertions
+  include JobsTestHelper
+
+  self.use_transactional_tests = false
+
+  test "does not clear ActiveRecord connections when feature is disabled" do
+    old_flag, SolidQueue.clear_connections_after_job = SolidQueue.clear_connections_after_job, false
+
+    AddToBufferJob.perform_later "no clear"
+
+    ActiveRecord::Base.expects(:clear_active_connections!).never
+
+    worker = SolidQueue::Worker.new(queues: "background", threads: 1, polling_interval: 0.1)
+    worker.start
+
+    wait_for_jobs_to_finish_for(2.seconds)
+    worker.stop
+  ensure
+    SolidQueue.clear_connections_after_job = old_flag
+  end
+end