add 'weave launch-proxy --with-ipam' flag

proxy/proxy.go

@@ -22,9 +22,10 @@ type Proxy struct {
 	client         *docker.Client
 	withDNS        bool
 	dockerBridgeIP string
+	withIPAM       bool
 }
 
-func NewProxy(targetURL string, withDNS bool) (*Proxy, error) {
+func NewProxy(targetURL string, withDNS, withIPAM bool) (*Proxy, error) {
 	u, err := url.Parse(targetURL)
 	if err != nil {
 		return nil, err
@@ -58,6 +59,7 @@ func NewProxy(targetURL string, withDNS bool) (*Proxy, error) {
 		client:         client,
 		withDNS:        withDNS,
 		dockerBridgeIP: string(dockerBridgeIP),
+		withIPAM:       withIPAM,
 	}, nil
 }
 
@@ -68,7 +70,7 @@ func (proxy *Proxy) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	case containerCreateRegexp.MatchString(path):
 		proxy.serveWithInterceptor(&createContainerInterceptor{proxy.client, proxy.withDNS, proxy.dockerBridgeIP}, w, r)
 	case containerStartRegexp.MatchString(path):
-		proxy.serveWithInterceptor(&startContainerInterceptor{proxy.client, proxy.withDNS}, w, r)
+		proxy.serveWithInterceptor(&startContainerInterceptor{proxy.client, proxy.withDNS, proxy.withIPAM}, w, r)
 	case execCreateRegexp.MatchString(path):
 		proxy.serveWithInterceptor(&createExecInterceptor{proxy.client}, w, r)
 	case strings.HasPrefix(path, "/weave"):

proxy/start_container_interceptor.go

@@ -9,8 +9,9 @@ import (
 )
 
 type startContainerInterceptor struct {
-	client  *docker.Client
-	withDNS bool
+	client   *docker.Client
+	withDNS  bool
+	withIPAM bool
 }
 
 func (i *startContainerInterceptor) InterceptRequest(r *http.Request) error {
@@ -24,25 +25,16 @@ func (i *startContainerInterceptor) InterceptResponse(r *http.Response) error {
 	}
 
 	cidrs, ok := weaveCIDRsFromConfig(container.Config)
-	if !ok {
+	if !ok && !i.withIPAM {
 		Debug.Print("No Weave CIDR, ignoring")
 		return nil
 	}
-	if len(cidrs) == 0 {
-		ipamCIDR, err := callWeave("ipam-cidr", container.ID)
-		if err != nil {
-			Warning.Printf("Determining container %s IP via IPAM failed: %v, %v", container.ID, err, string(ipamCIDR))
-			return nil
-		}
-		cidrs = strings.Fields(string(ipamCIDR))
-	}
 	Info.Printf("Attaching container %s with WEAVE_CIDR \"%s\" to weave network", container.ID, strings.Join(cidrs, " "))
 	args := []string{"attach"}
 	args = append(args, cidrs...)
 	args = append(args, container.ID)
 	if _, err := callWeave(args...); err != nil {
 		Warning.Printf("Attaching container %s to weave network failed: %v", container.ID, err)
-		return nil
 	}
 	return nil
 }

site/proxy.md

@@ -65,7 +65,11 @@ With this done, we can automtaically assign an address to a container by providi
 
     host1$ docker run -e WEAVE_CIDR= -ti ubuntu /bin/sh
 
-More details on IPAM can be found in the [IPAM documentstion](ipam.html).
+Alternatively, to enable automatic allocation of all containers without a `WEAVE_CIDR`, we can launch the proxy with the `--with-ipam` option. For example:
+
+    host1$ weave launch-proxy --with-ipam
+
+More details on IPAM can be found in the [IPAM documentation](ipam.html).
 
 ## Limitations
 

test/660_proxy_ipam_test.sh

@@ -9,11 +9,14 @@ start_suite "Ping proxied containers over cross-host weave network (with IPAM)"
 weave_on $HOST1 launch -iprange $UNIVERSE
 weave_on $HOST1 launch-proxy
 weave_on $HOST2 launch -iprange $UNIVERSE $HOST1
-weave_on $HOST2 launch-proxy
+weave_on $HOST2 launch-proxy --with-ipam
 
-proxy start_container $HOST1 -e WEAVE_CIDR= --name=c1
-proxy start_container $HOST2 -e WEAVE_CIDR= --name=c2
+proxy docker_on $HOST1 run -e WEAVE_CIDR= --name=c1 -dt $SMALL_IMAGE /bin/sh
+proxy docker_on $HOST2 run --name=c2 -dt $SMALL_IMAGE /bin/sh
+
+C1=$(container_ip $HOST1 c1)
 C2=$(container_ip $HOST2 c2)
-assert_raises "exec_on $HOST1 c1 $PING $C2"
+assert_raises "proxy exec_on $HOST1 c1 $PING $C2"
+assert_raises "proxy exec_on $HOST2 c2 $PING $C1"
 
 end_suite

weave

@@ -27,7 +27,7 @@ usage() {
     echo "weave setup"
     echo "weave launch       [-password <password>] [-nickname <nickname>] [-iprange <cidr>] <peer> ..."
     echo "weave launch-dns   <cidr>"
-    echo "weave launch-proxy [-H <docker_endpoint>] [--with-dns]"
+    echo "weave launch-proxy [-H <docker_endpoint>] [--with-dns] [--with-ipam]"
     echo "weave connect      <peer>"
     echo "weave forget       <peer>"
     echo "weave run          [--with-dns] [<cidr> ...] <docker run args> ..."
@@ -928,9 +928,6 @@ case "$COMMAND" in
         docker_bridge_ip
         echo -n $DOCKER_BRIDGE_IP
         ;;
-    ipam-cidr)
-        get_ipam_cidr "$@" && echo "$CIDR_ARGS"
-        ;;
     start)
         collect_cidr_args "$@"
         shift $CIDR_COUNT

weaveproxy/main.go

@@ -16,12 +16,13 @@ var (
 
 func main() {
 	var target, listen string
-	var withDNS, debug bool
+	var withDNS, withIPAM, debug bool
 
 	getopt.BoolVarLong(&debug, "debug", 'd', "log debugging information")
 	getopt.StringVar(&target, 'H', fmt.Sprintf("docker daemon URL to proxy (default %s)", defaultTarget))
 	getopt.StringVar(&listen, 'L', fmt.Sprintf("address on which to listen (default %s)", defaultListen))
 	getopt.BoolVarLong(&withDNS, "with-dns", 'w', "instruct created containers to use weaveDNS as their nameserver")
+	getopt.BoolVarLong(&withIPAM, "with-ipam", 'i', "automatically allocate addresses for containers without a WEAVE_CIDR")
 	getopt.Parse()
 
 	if target == "" {
@@ -36,7 +37,7 @@ func main() {
 		InitDefaultLogging(true)
 	}
 
-	p, err := proxy.NewProxy(target, withDNS)
+	p, err := proxy.NewProxy(target, withDNS, withIPAM)
 	if err != nil {
 		Error.Fatalf("Could not start proxy: %s", err)
 	}