Make getting the docker run comment easier.

weaveworks · Oct 12, 2015 · 36188a4 · 36188a4
1 parent 5e817e4
commit 36188a4
Showing 1 changed file with 17 additions and 5 deletions.
diff --git a/scope b/scope
@@ -6,6 +6,7 @@ usage() {
     echo "Usage:"
     echo "scope launch [<peer> ...]"
     echo "scope stop"
+    echo "scope command"
     echo
     echo "scope <peer>    is of the form <ip_address_or_fqdn>[:<port>]"
     exit 1
@@ -24,14 +25,18 @@ IP_REGEXP="[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}"
 IP_ADDR_CMD="find /sys/class/net -type l | xargs -n1 basename | grep -vE 'docker|veth|lo' | \
     xargs -n1 ip addr show | grep inet | awk '{ print \$2 }' | grep -oE '$IP_REGEXP'"
 WEAVESCOPE_DOCKER_ARGS=${WEAVESCOPE_DOCKER_ARGS:-}
+DOCKER=docker
+if [ -n "${DRY_RUN+x}" ]; then
+    DOCKER="echo docker"
+fi
 
 [ $# -gt 0 ] || usage
 COMMAND=$1
 shift 1
 
 # Check that a container named $1 with image $2 is not running
 check_not_running() {
-    case $(docker inspect --format='{{.State.Running}} {{.Config.Image}}' $1 2>/dev/null) in
+    case $($DOCKER inspect --format='{{.State.Running}} {{.Config.Image}}' $1 2>/dev/null) in
         "true $2")
             echo "$1 is already running." >&2
             exit 1
@@ -58,18 +63,25 @@ check_not_running() {
 }
 
 case "$COMMAND" in
+    command)
+        DRY_RUN=true $0 launch
+        ;;
 
     launch)
         check_not_running $SCOPE_CONTAINER_NAME $SCOPE_IMAGE
-        docker rm -f $SCOPE_CONTAINER_NAME >/dev/null 2>&1 || true
+        DOCKER rm -f $SCOPE_CONTAINER_NAME >/dev/null 2>&1 || true
 
-        CONTAINER=$(docker run --privileged -d --name=$SCOPE_CONTAINER_NAME --net=host --pid=host \
+
+        CONTAINER=$($DOCKER run --privileged -d --name=$SCOPE_CONTAINER_NAME --net=host --pid=host \
             -v /var/run/docker.sock:/var/run/docker.sock \
             $WEAVESCOPE_DOCKER_ARGS $SCOPE_IMAGE --probe.docker true "$@")
         echo $CONTAINER
+        if [ -n "${DRY_RUN+x}" ]; then
+            exit 0
+        fi
 
         if ! echo "$@" | grep -E "\-\-no\-app|\-\-service\-token" 1>/dev/null; then
-            IP_ADDRS=$(docker run --rm --net=host --entrypoint /bin/sh $SCOPE_IMAGE -c "$IP_ADDR_CMD")
+            IP_ADDRS=$($DOCKER run --rm --net=host --entrypoint /bin/sh $SCOPE_IMAGE -c "$IP_ADDR_CMD")
             echo "Weave Scope is reachable at the following URL(s):" >&2
             for ip in $IP_ADDRS; do
                 echo "  * http://$ip:4040/" >&2
@@ -79,7 +91,7 @@ case "$COMMAND" in
 
     stop)
         [ $# -eq 0 ] || usage
-        if ! docker stop $SCOPE_CONTAINER_NAME >/dev/null 2>&1 ; then
+        if ! $DOCKER stop $SCOPE_CONTAINER_NAME >/dev/null 2>&1 ; then
             echo "Weave Scope is not running." >&2
         fi
         ;;