From 264be0d2d4e61543902e79c0b092103400c283f7 Mon Sep 17 00:00:00 2001
From: Stewart Miles <stewart@agentic.ai>
Date: Thu, 16 Mar 2023 20:50:38 -0700
Subject: [PATCH] Retry until a leader is selected. (#4318)

Fixes regression introduced in
https://github.com/seaweedfs/seaweedfs/pull/4313

Related to #4307
---
 weed/topology/topology.go | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/weed/topology/topology.go b/weed/topology/topology.go
index 825c02961..fee4d6a03 100644
--- a/weed/topology/topology.go
+++ b/weed/topology/topology.go
@@ -101,7 +101,20 @@ func (t *Topology) Leader() (l pb.ServerAddress, err error) {
 	exponentialBackoff := backoff.NewExponentialBackOff()
 	exponentialBackoff.InitialInterval = 100 * time.Millisecond
 	exponentialBackoff.MaxElapsedTime = 20 * time.Second
-	return backoff.RetryWithData(t.MaybeLeader, exponentialBackoff)
+	leaderNotSelected := errors.New("leader not selected yet")
+	l, err = backoff.RetryWithData(
+		func() (l pb.ServerAddress, err error) {
+			l, err = t.MaybeLeader()
+			if err == nil && l == "" {
+				err = leaderNotSelected
+			}
+			return l, err
+		},
+		exponentialBackoff)
+	if err == leaderNotSelected {
+		l = ""
+	}
+	return l, err
 }
 
 func (t *Topology) MaybeLeader() (l pb.ServerAddress, err error) {