support AllowStale reads for consul topo when polling

Signed-off-by: Michael Demmer <mdemmer@slack-corp.com>
slackhq · Nov 15, 2024 · a1889da · a1889da
1 parent f93a9a1
commit a1889da
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Showing 2 changed files with 8 additions and 1 deletion.
diff --git a/go/vt/topo/consultopo/file.go b/go/vt/topo/consultopo/file.go
@@ -102,7 +102,12 @@ func (s *Server) Get(ctx context.Context, filePath string) ([]byte, topo.Version
 func (s *Server) List(ctx context.Context, filePathPrefix string, polling bool) ([]topo.KVInfo, error) {
 	nodePathPrefix := path.Join(s.root, filePathPrefix)
 
-	pairs, _, err := s.kv.List(nodePathPrefix, nil)
+	opts := api.QueryOptions{}
+	if consulAllowStalePolling && polling {
+		opts.AllowStale = true
+	}
+
+	pairs, _, err := s.kv.List(nodePathPrefix, &opts)
 	if err != nil {
 		return []topo.KVInfo{}, err
 	}

diff --git a/go/vt/topo/consultopo/server.go b/go/vt/topo/consultopo/server.go
@@ -41,6 +41,7 @@ var (
 	consulLockSessionChecks = "serfHealth"
 	consulLockSessionTTL    string
 	consulLockDelay         = 15 * time.Second
+	consulAllowStalePolling bool
 )
 
 func init() {
@@ -52,6 +53,7 @@ func registerServerFlags(fs *pflag.FlagSet) {
 	fs.StringVar(&consulLockSessionChecks, "topo_consul_lock_session_checks", consulLockSessionChecks, "List of checks for consul session.")
 	fs.StringVar(&consulLockSessionTTL, "topo_consul_lock_session_ttl", consulLockSessionTTL, "TTL for consul session.")
 	fs.DurationVar(&consulLockDelay, "topo_consul_lock_delay", consulLockDelay, "LockDelay for consul session.")
+	fs.BoolVar(&consulAllowStalePolling, "topo_consul_allow_stale_polling", consulAllowStalePolling, "Set AllowStale as an option when reading in a polling context.")
 }
 
 // ClientAuthCred credential to use for consul clusters