From 5c0ceec2a62e2c1003aa72b4fa78bb09e53c3a84 Mon Sep 17 00:00:00 2001
From: Till <2353100+S7evinK@users.noreply.github.com>
Date: Tue, 9 Apr 2024 07:49:56 +0200
Subject: [PATCH] Don't attempt to send transactions if Dendrite is shutting
 down (#3356)

This should avoid confusions with logs like:

```
time="2024-04-08T08:38:45.104235081Z" level=error msg="Failed to set \"scs.ems.host\" as assumed offline" func="github.com/matrix-org/dendrite/federationapi/statistics.(*ServerStatistics).Failure" file="github.com/matrix-org/dendrite/federationapi/statistics/statistics.go:204" error="sqlutil.WithTransaction.Begin: sql: database is closed"
time="2024-04-08T08:38:45.104239201Z" level=error msg="Failed to set \"obermui.de\" as assumed offline" func="github.com/matrix-org/dendrite/federationapi/statistics.(*ServerStatistics).Failure" file="github.com/matrix-org/dendrite/federationapi/statistics/statistics.go:204" error="sqlutil.WithTransaction.Begin: sql: database is closed"
```

or

```
time="2024-04-08T08:38:45.105235411Z" level=error msg="Failed to get pending EDUs for \"retro76.net\"" func="github.com/matrix-org/dendrite/federationapi/queue.(*destinationQueue).getPendingFromDatabase" file="github.com/matrix-org/dendritefederationapi/queue/destinationqueue.go:258" error="sqlutil.WithTransaction.Begin: sql: database is closed"
```

[skip ci]
---
 federationapi/queue/destinationqueue.go | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/federationapi/queue/destinationqueue.go b/federationapi/queue/destinationqueue.go
index f51e849fa..87a6fe559 100644
--- a/federationapi/queue/destinationqueue.go
+++ b/federationapi/queue/destinationqueue.go
@@ -294,6 +294,10 @@ func (oq *destinationQueue) checkNotificationsOnClose() {
 
 // backgroundSend is the worker goroutine for sending events.
 func (oq *destinationQueue) backgroundSend() {
+	// Don't try to send transactions if we are shutting down.
+	if oq.process.Context().Err() != nil {
+		return
+	}
 	// Check if a worker is already running, and if it isn't, then
 	// mark it as started.
 	if !oq.running.CompareAndSwap(false, true) {