From ec6318befc5f02a602eb88d6cc028af004e92865 Mon Sep 17 00:00:00 2001
From: Milos Gajdos <milosgajdos83@gmail.com>
Date: Tue, 3 Sep 2019 10:00:14 +0100
Subject: [PATCH] Prune nodes that have not announced themselves for certain
time period.
---
network/default.go | 61 ++++++++++++++++++++++++++++++++++++++++++++--
network/network.go | 3 +++
2 files changed, 62 insertions(+), 2 deletions(-)
diff --git a/network/default.go b/network/default.go
index b0c77f62..6e91c59c 100644
--- a/network/default.go
+++ b/network/default.go
@@ -36,8 +36,10 @@ type node struct {
address string
// neighbours maps the node neighbourhood
neighbours map[string]*node
- // network returns network node is in
+ // network returns the node network
network Network
+ // lastSeen stores the time the node has been seen last time
+ lastSeen time.Time
}
// Id is node ide
@@ -307,6 +309,7 @@ func (n *network) processNetChan(l tunnel.Listener) {
id: pbNetNeighbour.Node.Id,
address: pbNetNeighbour.Node.Address,
neighbours: make(map[string]*node),
+ lastSeen: time.Now(),
}
n.Lock()
// we override the existing neighbour map
@@ -331,7 +334,10 @@ func (n *network) processNetChan(l tunnel.Listener) {
continue
}
n.Lock()
- delete(n.neighbours, pbNetClose.Node.Id)
+ if err := n.pruneNode(pbNetClose.Node.Id); err != nil {
+ log.Debugf("Network failed to prune the node %s: %v", pbNetClose.Node.Id, err)
+ continue
+ }
n.Unlock()
}
case <-n.closed:
@@ -393,6 +399,55 @@ func (n *network) announce(client transport.Client) {
}
}
+// pruneNode removes a node with given id from the list of neighbours. It also removes all routes originted by this node.
+// NOTE: this method is not thread-safe; when calling it make sure you lock the particular code segment
+func (n *network) pruneNode(id string) error {
+ delete(n.neighbours, id)
+ // lookup all the routes originated at this node
+ q := router.NewQuery(
+ router.QueryRouter(id),
+ )
+ routes, err := n.Router.Table().Query(q)
+ if err != nil && err != router.ErrRouteNotFound {
+ return err
+ }
+ // delete the found routes
+ for _, route := range routes {
+ if err := n.Router.Table().Delete(route); err != nil && err != router.ErrRouteNotFound {
+ return err
+ }
+ }
+
+ return nil
+}
+
+// prune the nodes that have not been seen for certain period of time defined by PruneTime
+// Additionally, prune also removes all the routes originated by these nodes
+func (n *network) prune() {
+ prune := time.NewTicker(PruneTime)
+ defer prune.Stop()
+
+ for {
+ select {
+ case <-n.closed:
+ return
+ case <-prune.C:
+ n.Lock()
+ for id, node := range n.neighbours {
+ nodeAge := time.Since(node.lastSeen)
+ if nodeAge > PruneTime {
+ log.Debugf("Network deleting node %s: reached prune time threshold", id)
+ if err := n.pruneNode(id); err != nil {
+ log.Debugf("Network failed to prune the node %s: %v", id, err)
+ continue
+ }
+ }
+ }
+ n.Unlock()
+ }
+ }
+}
+
// handleCtrlConn handles ControlChannel connections
func (n *network) handleCtrlConn(sess tunnel.Session, msg chan *transport.Message) {
for {
@@ -695,6 +750,8 @@ func (n *network) Connect() error {
go n.resolve()
// broadcast neighbourhood
go n.announce(netClient)
+ // prune stale nodes
+ go n.prune()
// listen to network messages
go n.processNetChan(netListener)
// advertise service routes
diff --git a/network/network.go b/network/network.go
index f68cc147..5a9b7f6a 100644
--- a/network/network.go
+++ b/network/network.go
@@ -17,6 +17,9 @@ var (
ResolveTime = 1 * time.Minute
// AnnounceTime defines time interval to periodically announce node neighbours
AnnounceTime = 30 * time.Second
+ // PruneTime defines time interval to periodically check nodes that need to be pruned
+ // due to their not announcing their presence within this time interval
+ PruneTime = 90 * time.Second
)
// Node is network node