Merge pull request #147 from bboreham/138_weave_ps

Add command `weave ps`

weave

@@ -11,6 +11,7 @@ usage() {
     echo "weave detach  <cidr> <container_id>"
     echo "weave expose  <cidr>"
     echo "weave hide    <cidr>"
+    echo "weave ps"
     echo "weave status"
     echo "weave version"
     echo "weave stop"
@@ -146,6 +147,9 @@ docker_ip() {
 }
 
 # the following borrows from https://github.com/jpetazzo/pipework
+
+# run args $2 $3 ... as a command in the network namespace of container $1
+# if an error is caused by container dying, swallow output from error
 with_container_netns () {
     CONTAINER="$1"
     CONTAINER_PID=$(docker inspect --format='{{ .State.Pid }}' $CONTAINER)
@@ -183,6 +187,7 @@ with_container_netns () {
         fi
     fi
 
+    cat $IP_TMPFILE  # no error - send the output to stdout
     rm -f $IP_TMPFILE /var/run/netns/$NETNS
     return $STATUS
 }
@@ -258,6 +263,10 @@ detach() {
     ip link del $LOCAL_IFNAME type veth
 }
 
+container_weave_addrs() {
+    ip netns exec $NETNS ip addr show dev $CONTAINER_IFNAME
+}
+
 case "$COMMAND" in
     launch)
         case $(docker inspect --format '{{ .State.Running }} {{ .Config.Image }}' $CONTAINER_NAME 2>/dev/null) in
@@ -294,7 +303,7 @@ case "$COMMAND" in
         # additional parameters, such as resource limits, to docker
         # when launching the weave container.
         CONTAINER=$(docker run --privileged -d --name=$CONTAINER_NAME -p $PORT:$PORT/tcp -p $PORT:$PORT/udp $WEAVE_DOCKER_ARGS $IMAGE -name $MACADDR "$@" | tail -n 1)
-        with_container_netns $CONTAINER launch
+        with_container_netns $CONTAINER launch >/dev/null
         echo $CONTAINER
         ;;
     connect)
@@ -319,6 +328,16 @@ case "$COMMAND" in
             exit 1
         fi
         ;;
+    ps)
+        [ $# -eq 0 ] || usage
+        for CONTAINER_ID in $(docker ps -q) ; do
+            if CONTAINER_ADDRS=$(with_container_netns $CONTAINER_ID container_weave_addrs 2>&1) ; then
+                CONTAINER_MAC=$(echo "$CONTAINER_ADDRS" | grep -o 'link/ether .*' | cut -d ' ' -f 2)
+                CONTAINER_IPS=$(echo "$CONTAINER_ADDRS" | grep -o 'inet .*'       | cut -d ' ' -f 2)
+                echo $CONTAINER_ID $CONTAINER_MAC $CONTAINER_IPS
+            fi
+        done
+        ;;
     version)
         [ $# -eq 0 ] || usage
         # Try the running container first; if no luck try the image
@@ -337,7 +356,7 @@ case "$COMMAND" in
         shift 1
         create_bridge
         CONTAINER=$(docker run -d "$@" | tail -n 1)
-        with_container_netns $CONTAINER attach $CIDR
+        with_container_netns $CONTAINER attach $CIDR >/dev/null
         echo $CONTAINER
         ;;
     start)
@@ -345,19 +364,19 @@ case "$COMMAND" in
         validate_cidr $1
         create_bridge
         CONTAINER=$(docker start $2)
-        with_container_netns $CONTAINER attach $1
+        with_container_netns $CONTAINER attach $1 >/dev/null
         echo $CONTAINER
         ;;
     attach)
         [ $# -eq 2 ] || usage
         validate_cidr $1
         create_bridge
-        with_container_netns $2 attach $1
+        with_container_netns $2 attach $1 >/dev/null
         ;;
     detach)
         [ $# -eq 2 ] || usage
         validate_cidr $1
-        with_container_netns $2 detach $1
+        with_container_netns $2 detach $1 >/dev/null
         ;;
     expose)
         [ $# -eq 1 ] || usage