Implement weave launch --resume

prog/weaver/main.go

@@ -151,6 +151,7 @@ func main() {
 		config             mesh.Config
 		networkConfig      weave.NetworkConfig
 		protocolMinVersion int
+		resume             bool
 		ifaceName          string
 		routerName         string
 		nickName           string
@@ -181,6 +182,7 @@ func main() {
 	mflag.StringVar(&config.Host, []string{"-host"}, "", "router host")
 	mflag.IntVar(&config.Port, []string{"#port", "-port"}, mesh.Port, "router port")
 	mflag.IntVar(&protocolMinVersion, []string{"-min-protocol-version"}, mesh.ProtocolMinVersion, "minimum weave protocol version")
+	mflag.BoolVar(&resume, []string{"-resume"}, false, "resume connections to previous peers")
 	mflag.StringVar(&ifaceName, []string{"#iface", "-iface"}, "", "name of interface to capture/inject from (disabled if blank)")
 	mflag.StringVar(&routerName, []string{"#name", "-name"}, "", "name of router (defaults to MAC of interface)")
 	mflag.StringVar(&nickName, []string{"#nickname", "-nickname"}, "", "nickname of peer (defaults to hostname)")
@@ -218,6 +220,9 @@ func main() {
 	mflag.Parse()
 
 	peers = mflag.Args()
+	if resume && len(peers) > 0 {
+		Log.Fatalf("You must not specify an initial peer list in conjuction with --resume")
+	}
 
 	common.SetLogLevel(logLevel)
 
@@ -267,7 +272,7 @@ func main() {
 	router := weave.NewNetworkRouter(config, networkConfig, name, nickName, overlay, db)
 	Log.Println("Our name is", router.Ourself)
 
-	if peers, err = router.InitialPeers(peers); err != nil {
+	if peers, err = router.InitialPeers(resume, peers); err != nil {
 		Log.Fatal("Unable to get initial peer set: ", err)
 	}
 

router/network_router.go

@@ -230,13 +230,13 @@ func (router *NetworkRouter) ForgetConnections(peers []string) {
 	router.persistPeers()
 }
 
-func (router *NetworkRouter) InitialPeers(peers []string) ([]string, error) {
-	if _, err := os.Stat("restart.sentinel"); err == nil {
+func (router *NetworkRouter) InitialPeers(resume bool, peers []string) ([]string, error) {
+	if _, err := os.Stat("restart.sentinel"); err == nil || resume {
 		var storedPeers []string
 		if _, err := router.db.Load(peersIdent, &storedPeers); err != nil {
 			return nil, err
 		}
-		log.Println("Restart detected - using persisted peer list:", storedPeers)
+		log.Println("Restart/resume detected - using persisted peer list:", storedPeers)
 		return storedPeers, nil
 	}
 

weave

@@ -45,7 +45,7 @@ weave launch        <same arguments as 'weave launch-router'>
                       [--no-restart] [--ipalloc-init <mode>]
                       [--ipalloc-range <cidr> [--ipalloc-default-subnet <cidr>]]
                       [--no-discovery] [--no-dns]
-                      [--trusted-subnets <cidr>,...] <peer> ...
+                      [--trusted-subnets <cidr>,...] [--resume] <peer> ...
       launch-proxy  [-H <endpoint>] [--without-dns] [--no-multicast-route]
                       [--log-level=debug|info|warning|error]
                       [--no-rewrite-hosts] [--no-default-ipalloc] [--no-restart]