Merge pull request #705 from libp2p/feat/unlock-refresh

Routing table refresh should NOT block

Author: Stebalien

rtrefresh/rt_refresh_manager.go

@@ -102,15 +102,18 @@ func (r *RtRefreshManager) Close() error {
 //
 // The returned channel will block until the refresh finishes, then yield the
 // error and close. The channel is buffered and safe to ignore.
-// FIXME: this can block. Ideally, we'd return a channel without blocking.
-// https://github.com/libp2p/go-libp2p-kad-dht/issues/609
 func (r *RtRefreshManager) Refresh(force bool) <-chan error {
 	resp := make(chan error, 1)
-	select {
-	case r.triggerRefresh <- &triggerRefreshReq{respCh: resp, forceCplRefresh: force}:
-	case <-r.ctx.Done():
-		resp <- r.ctx.Err()
-	}
+	r.refcount.Add(1)
+	go func() {
+		defer r.refcount.Done()
+		select {
+		case r.triggerRefresh <- &triggerRefreshReq{respCh: resp, forceCplRefresh: force}:
+		case <-r.ctx.Done():
+			resp <- r.ctx.Err()
+		}
+	}()
+
 	return resp
 }