File watch on shutdown

exporter/collector/metrics.go

@@ -599,14 +599,18 @@ func (me *MetricsExporter) runWALReadAndExportLoop(ctx context.Context) {
 			// do one last final read/export then return
 			// otherwise the runner goroutine could leave some hanging metrics unexported
 			for {
-				fmt.Println("Reading WAL final time")
 				err := me.readWALAndExport(runCtx)
 				if err != nil {
-					if !errors.Is(err, wal.ErrOutOfRange) {
-						me.obs.log.Error(fmt.Sprintf("error flushing remaining WAL entries: %+v", err))
+					me.obs.log.Error(fmt.Sprintf("error flushing remaining WAL entries: %+v", err))
+					if errors.Is(err, wal.ErrOutOfRange) {
+						break
+					}
+					if errors.Is(err, wal.ErrNotFound) {
+						if err2 := me.watchWALFile(ctx); err2 != nil {
+							me.obs.log.Error(fmt.Sprintf("error flushing remaining WAL entries: %+v", err2))
+							break
+						}
 					}
-					fmt.Println(err)
-					break
 				}
 			}
 			return