don't remove itself if node is a raft leader

Makefile

@@ -37,7 +37,7 @@ release:
 		-e DOCKER_USERNAME \
 		-e DOCKER_PASSWORD \
 		-e DOCKER_REGISTRY \
-		-e GORELEASER_CURRENT_TAG=v3.2.7-M3 \
+		-e GORELEASER_CURRENT_TAG=v3.2.7-M4 \
 		-v /var/run/docker.sock:/var/run/docker.sock \
 		goreleaser/goreleaser-cross:${GOLANG_CROSS_VERSION} \
 		release --rm-dist --skip-validate --timeout=1h

dkron/leader.go

@@ -3,6 +3,7 @@ package dkron
 import (
 	"fmt"
 	"net"
+	"strings"
 	"sync"
 	"time"
 
@@ -315,6 +316,15 @@ func (a *Agent) addRaftPeer(m serf.Member, parts *ServerParts) error {
 // removeRaftPeer is used to remove a Raft peer when a dkron server leaves
 // or is reaped
 func (a *Agent) removeRaftPeer(m serf.Member, parts *ServerParts) error {
+
+	// Do not remove ourself. This can only happen if the current leader
+	// is leaving. Instead, we should allow a follower to take-over and
+	// deregister us later.
+	if strings.EqualFold(m.Name, a.config.NodeName) {
+		a.logger.Warn("removing self should be done by follower", "name", a.config.NodeName)
+		return nil
+	}
+
 	// See if it's already in the configuration. It's harmless to re-remove it
 	// but we want to avoid doing that if possible to prevent useless Raft
 	// log entries.