From a113da0e34b2cd9620354fbe2702930f6f1a618e Mon Sep 17 00:00:00 2001
From: Bryan Boreham <bjboreham@gmail.com>
Date: Fri, 29 Aug 2014 14:44:50 +0100
Subject: [PATCH] Added a new command 'weave status', implemented via an http
 listener #11

---
 consts.go         |  1 +
 http_responder.go | 34 ++++++++++++++++++++++++++++++++++
 weaver/main.go    |  6 ++++--
 weaver/weave      | 24 +++++++++++++++++++++---
 4 files changed, 60 insertions(+), 5 deletions(-)
 create mode 100644 http_responder.go

diff --git a/consts.go b/consts.go
index 106e1c8e..6d4074a2 100644
--- a/consts.go
+++ b/consts.go
@@ -10,6 +10,7 @@ const (
 	EthernetOverhead  = 14
 	UDPOverhead       = 28 // 20 bytes for IPv4, 8 bytes for UDP
 	Port              = 6783
+	StatusPort        = Port+1
 	DefaultPMTU       = 65535
 	MaxUDPPacketSize  = 65536
 	ChannelSize       = 16
diff --git a/http_responder.go b/http_responder.go
new file mode 100644
index 00000000..bf2ff05c
--- /dev/null
+++ b/http_responder.go
@@ -0,0 +1,34 @@
+package weave
+
+import (
+	"fmt"
+    "net/http"
+)
+
+/* A simple http responder that will show the status of the router when asked,
+ e.g. via http://172.17.0.2/status
+*/
+type HttpStatusResponder struct {
+    router *Router
+}
+
+func NewHttpStatusResponder(router *Router) *HttpStatusResponder {
+    resp := &HttpStatusResponder{router}
+    return resp
+}
+
+func (resp *HttpStatusResponder) SetRouter(newRouter *Router) {
+    resp.router = newRouter
+}
+
+func (resp *HttpStatusResponder) ListenAndServe() {
+    http.HandleFunc("/status", func(w http.ResponseWriter, r *http.Request) {
+        if resp.router != nil {
+            fmt.Fprint(w, resp.router.Status())
+        } else {
+            fmt.Fprintf(w, "Not initialized")
+        }
+    })
+    address := fmt.Sprintf(":%d", StatusPort)
+    http.ListenAndServe(address, nil)
+}
diff --git a/weaver/main.go b/weaver/main.go
index 174f9f93..27e89912 100644
--- a/weaver/main.go
+++ b/weaver/main.go
@@ -1,7 +1,7 @@
 package main
 
 import (
-	"github.com/zettio/weave"
+	"github.com/bboreham/weave"
 	"code.google.com/p/gopacket/layers"
 	"crypto/sha256"
 	"flag"
@@ -70,7 +70,7 @@ func main() {
 	flag.IntVar(&bufSz, "bufsz", 8, "capture buffer size in MB (defaults to 8MB)")
 	flag.Parse()
 	peers = flag.Args()
-
+    
 	if ifaceName == "" {
 		fmt.Println("Missing required parameter 'iface'")
 		os.Exit(1)
@@ -123,6 +123,8 @@ func main() {
 			}
 		}()
 	}
+    httpResponder := weave.NewHttpStatusResponder(router)
+    go httpResponder.ListenAndServe()
 	handleSignals(router)
 }
 
diff --git a/weaver/weave b/weaver/weave
index e6bd3143..a7dee039 100755
--- a/weaver/weave
+++ b/weaver/weave
@@ -13,10 +13,14 @@ usage() {
     echo "Usage:"
     echo "weave <ipaddr>/<subnet> launch [-passwd <passwd>] <peer_host> ..."
     echo "weave <ipaddr>/<subnet> run <docker run args> ..."
+    echo "weave status"
     exit 1
 }
 
-shift 2 || usage
+if [ "$#" -lt 1 ]; then
+    usage
+exit 1
+fi
 
 [ `id -u` = 0 ] || {
     echo "weave must be run as 'root'"
@@ -46,10 +50,25 @@ MACADDR=`cat /sys/class/net/$BRIDGE/address`
 
 case "$COMMAND" in
     launch)
+        shift 2
         CONTAINER=$(docker run --privileged -d --name=weave -p 6783:6783/tcp -p 6783:6783/udp $WEAVE_DOCKER_ARGS zettio/weave -name $MACADDR "$@")
         IFACE=eth0
         ;;
+    status)
+        DOCKERIP=$(docker inspect --format='{{ .NetworkSettings.IPAddress }}' weave)
+        if command -v wget >/dev/null 2>&1 ; then
+            wget -O - -q $DOCKERIP:6784/status
+        elif command -v curl >/dev/null 2>&1 ; then
+            curl $DOCKERIP:6784/status
+        else
+            echo "weave status needs either curl or wget to function" >&2
+            exit 1
+        fi
+        # return the status from the wget or curl command, so if they fail then we fail.
+        exit $?
+        ;;
     run)
+        shift 2
         CONTAINER=$(docker run -d "$@")
         IFACE=$CONTAINER_IFNAME
         ;;
@@ -87,8 +106,7 @@ ip netns exec $NSPID ip link set $GUEST_IFNAME name $CONTAINER_IFNAME
 ip netns exec $NSPID ip addr add $IPADDR dev $CONTAINER_IFNAME
 ip netns exec $NSPID ip link set $CONTAINER_IFNAME up
 
-if [ command -v ethtool >/dev/null 2>&1 ]
-then
+if command -v ethtool >/dev/null 2>&1 ; then
     ip netns exec $NSPID ethtool -K $IFACE tx off > /dev/null
 else
     echo "Cannot find ethtool; continuing without it" >&2