@@ -421,12 +421,17 @@ func (api *API) updaterLoop() {
421421// advancing the clock.
422422ticker := api .clock .TickerFunc (api .ctx ,api .updateInterval ,func ()error {
423423done := make (chan error ,1 )
424- defer close (done )
425-
424+ var sent bool
425+ defer func () {
426+ if ! sent {
427+ close (done )
428+ }
429+ }()
426430select {
427431case <- api .ctx .Done ():
428432return api .ctx .Err ()
429433case api .updateTrigger <- done :
434+ sent = true
430435err := <- done
431436if err != nil {
432437if errors .Is (err ,context .Canceled ) {
@@ -455,6 +460,7 @@ func (api *API) updaterLoop() {
455460// Note that although we pass api.ctx here, updateContainers
456461// has an internal timeout to prevent long blocking calls.
457462done <- api .updateContainers (api .ctx )
463+ close (done )
458464}
459465}
460466}
@@ -798,12 +804,19 @@ func (api *API) RefreshContainers(ctx context.Context) (err error) {
798804}()
799805
800806done := make (chan error ,1 )
807+ var sent bool
808+ defer func () {
809+ if ! sent {
810+ close (done )
811+ }
812+ }()
801813select {
802814case <- api .ctx .Done ():
803815return xerrors .Errorf ("API closed: %w" ,api .ctx .Err ())
804816case <- ctx .Done ():
805817return ctx .Err ()
806818case api .updateTrigger <- done :
819+ sent = true
807820select {
808821case <- api .ctx .Done ():
809822return xerrors .Errorf ("API closed: %w" ,api .ctx .Err ())