matsukaz · October 22, 2024 06:09 · Jul 31, 2017 · Jul 31, 2017
diff --git a/application.rb b/application.rb
@@ -0,0 +1,9 @@
+module xxx
+  class Application < Rails::Application
+
+   #（中略）
+
+    config.middleware.swap ActiveRecord::ConnectionAdapters::ConnectionManagement,
+                           'ActiveRecord::ConnectionAdapters::ReconnectOnErrorManagement'
+  end
+end
diff --git a/reconnect_on_error_management.rb b/reconnect_on_error_management.rb
@@ -0,0 +1,40 @@
+module ActiveRecord
+  module ConnectionAdapters
+    class ReconnectOnErrorManagement
+      CONNECTION_ERROR = ['Lost connection', 'gone away', '--read-only']
+      CONNECTION_ERROR_RE = /#{CONNECTION_ERROR.map{|w|Regexp.escape(w)}.join('|')}/
+      CONNECTION_ERROR_RE.freeze
+
+      def initialize(app)
+        @app = app
+      end
+
+      def call(env)
+        testing = env.key?('rack.test')
+
+        response = @app.call(env)
+        response[2] = ::Rack::BodyProxy.new(response[2]) do
+          ActiveRecord::Base.clear_active_connections! unless testing
+        end
+
+        response
+      rescue Exception => e
+        unless testing
+          if should_clear_all_connections?(e)
+            ActiveRecord::Base.clear_all_connections!
+          else
+            ActiveRecord::Base.clear_active_connections!
+          end
+        end
+        raise
+      end
+
+      def should_clear_all_connections?(e)
+        if e.kind_of?(ActiveRecord::StatementInvalid)
+          return CONNECTION_ERROR_RE === e.message
+        end
+        return false
+      end
+    end
+  end
+end