Merge pull request #794 from paulbellamy/connect-replace

add 'weave connect --replace ...'

Closes #658.

router/connection_maker.go

@@ -14,12 +14,14 @@ const (
 	MaxInterval     = 10 * time.Minute
 )
 
+type peerAddrs map[string]*net.TCPAddr
+
 type ConnectionMaker struct {
 	ourself     *LocalPeer
 	peers       *Peers
 	port        int
 	targets     map[string]*Target
-	directPeers map[string]*net.TCPAddr
+	directPeers peerAddrs
 	actionChan  chan<- ConnectionMakerAction
 }
 
@@ -38,7 +40,7 @@ func NewConnectionMaker(ourself *LocalPeer, peers *Peers, port int) *ConnectionM
 		ourself:     ourself,
 		peers:       peers,
 		port:        port,
-		directPeers: make(map[string]*net.TCPAddr),
+		directPeers: peerAddrs{},
 		targets:     make(map[string]*Target)}
 }
 
@@ -48,9 +50,9 @@ func (cm *ConnectionMaker) Start() {
 	go cm.queryLoop(actionChan)
 }
 
-func (cm *ConnectionMaker) InitiateConnections(peers []string) []error {
+func (cm *ConnectionMaker) InitiateConnections(peers []string, replace bool) []error {
 	errors := []error{}
-	addrs := make(map[string]*net.TCPAddr)
+	addrs := peerAddrs{}
 	for _, peer := range peers {
 		host, port, err := net.SplitHostPort(peer)
 		if err != nil {
@@ -64,6 +66,9 @@ func (cm *ConnectionMaker) InitiateConnections(peers []string) []error {
 		}
 	}
 	cm.actionChan <- func() bool {
+		if replace {
+			cm.directPeers = peerAddrs{}
+		}
 		for peer, addr := range addrs {
 			cm.directPeers[peer] = addr
 			// curtail any existing reconnect interval

site/features.md

@@ -368,6 +368,11 @@ This will prevent the peer from trying to reconnect to that host once
 connectivity to it is lost, and thus can be used to administratively
 remove decommissioned peers from the network.
 
+Hosts can also be bulk-replaced. All existing hosts will be forgotten,
+and the new hosts will be added, when one runs
+
+    host# weave connect --replace $NEW_HOST1 $NEW_HOST2
+
 ### <a name="container-mobility"></a>Container mobility
 
 Containers can be moved between hosts without requiring any

test/150_connect_forget_test.sh

@@ -6,17 +6,11 @@ C1=10.2.1.4
 C2=10.2.1.7
 
 direct_peers() {
-  weave_on $1 status | awk "/^Direct Peers:$/{f=1;next} /Reconnects:/{f=0} f"
+  weave_on $1 status | awk "/^Direct Peers:$/{f=1;next} /Reconnects:/{f=0} f" | sort
 }
 
-assert_connected() {
-  assert_raises "direct_peers $HOST2 | grep '^$HOST1$'"
-  assert_raises "exec_on $HOST1 c1 $PING $C2"
-}
-
-assert_disconnected() {
-  assert "direct_peers $HOST2" ""
-  assert_raises "exec_on $HOST1 c1 sh -c '! $PING $C2'"
+assert_peers() {
+  assert "direct_peers $1" "$(echo "$2" | sort)"
 }
 
 start_suite "Connecting and forgetting routers after launch"
@@ -27,14 +21,21 @@ weave_on $HOST2 launch
 start_container $HOST1 $C1/24 --name=c1
 start_container $HOST2 $C2/24 --name=c2
 
-assert_disconnected
-assert_raises "weave_on $HOST2 connect $HOST1 $HOST2"
-assert_connected
+# Connect to some bogus hosts
+assert_raises "weave_on $HOST2 connect 10.2.2.1 10.2.2.2"
+assert_peers $HOST2 "10.2.2.1\n10.2.2.2"
 
+# Replace bogus hosts with real hosts
+assert_raises "exec_on $HOST1 c1 sh -c '! $PING $C2'"
+assert_raises "weave_on $HOST2 connect --replace $HOST1 $HOST2"
+assert_peers $HOST2 "$HOST1\n$HOST2"
+assert_raises "exec_on $HOST1 c1 $PING $C2"
+
+# Forget everyone and disonnect
 assert_raises "weave_on $HOST2 forget $HOST1 $HOST2"
 assert_raises "weave_on $HOST1 stop"
 assert_raises "weave_on $HOST1 launch"
-
-assert_disconnected
+assert_peers $HOST2 ""
+assert_raises "exec_on $HOST1 c1 sh -c '! $PING $C2'"
 
 end_suite

weave

@@ -28,7 +28,7 @@ usage() {
     echo "weave launch       [-password <password>] [-nickname <nickname>] [-iprange <cidr>] <peer> ..."
     echo "weave launch-dns   <cidr>"
     echo "weave launch-proxy [-H <docker_endpoint>] [--with-dns] [--with-ipam]"
-    echo "weave connect      <peer> ..."
+    echo "weave connect      [--replace] [<peer> ...]"
     echo "weave forget       <peer> ..."
     echo "weave run          [--with-dns] [<cidr> ...] <docker run args> ..."
     echo "weave start        [<cidr> ...] <container_id>"
@@ -871,7 +871,11 @@ case "$COMMAND" in
         ;;
     connect)
         [ $# -gt 0 ] || usage
-        http_call $CONTAINER_NAME $HTTP_PORT POST /connect -d $(peer_args "$@")
+        if [ "$1" == "--replace" ]; then
+          replace="-d replace=true"
+          shift
+        fi
+        http_call $CONTAINER_NAME $HTTP_PORT POST /connect $replace -d $(peer_args "$@")
         ;;
     forget)
         [ $# -gt 0 ] || usage

weaver/main.go

@@ -144,7 +144,7 @@ func main() {
 	}
 
 	router.Start()
-	if errors := router.ConnectionMaker.InitiateConnections(peers); len(errors) > 0 {
+	if errors := router.ConnectionMaker.InitiateConnections(peers, false); len(errors) > 0 {
 		log.Fatal(errorMessages(errors))
 	}
 
@@ -256,7 +256,7 @@ func handleHTTP(router *weave.Router, httpAddr string, allocator *ipam.Allocator
 		if err := r.ParseForm(); err != nil {
 			http.Error(w, fmt.Sprint("unable to parse form: ", err), http.StatusBadRequest)
 		}
-		if errors := router.ConnectionMaker.InitiateConnections(r.Form["peer"]); len(errors) > 0 {
+		if errors := router.ConnectionMaker.InitiateConnections(r.Form["peer"], r.FormValue("replace") == "true"); len(errors) > 0 {
 			http.Error(w, errorMessages(errors), http.StatusBadRequest)
 		}
 	})