Automatically clean up KUBE_TEMP

kube::util:ensure-temp-dir claims that it will automatically clean it
up. But it obviously doesn't. Since we cannot add multiple trap in bash
add a function that lets us trap and clean up KUBE_TEMP even if someone
already set a trap.

hack/lib/util.sh

@@ -48,6 +48,36 @@ kube::util::wait_for_url() {
   return 1
 }
 
+# Example:  kube::util::trap_add 'echo "in trap DEBUG"' DEBUG
+# See: http://stackoverflow.com/questions/3338030/multiple-bash-traps-for-the-same-signal
+kube::util::trap_add() {
+  local trap_add_cmd
+  trap_add_cmd=$1
+  shift
+
+  for trap_add_name in "$@"; do
+    local existing_cmd
+    local new_cmd
+
+    # Grab the currently defined trap commands for this trap
+    existing_cmd=`trap -p "${trap_add_name}" |  awk -F"'" '{print $2}'`
+
+    if [[ -z "${existing_cmd}" ]]; then
+      new_cmd="${trap_add_cmd}"
+    else
+      new_cmd="${existing_cmd};${trap_add_cmd}"
+    fi
+
+    # Assign the test
+    trap "${new_cmd}" "${trap_add_name}"
+  done
+}
+
+# Opposite of kube::util::ensure-temp-dir()
+kube::util::cleanup-temp-dir() {
+  rm -rf "${KUBE_TEMP}"
+}
+
 # Create a temp dir that'll be deleted at the end of this bash session.
 #
 # Vars set:
@@ -55,6 +85,7 @@ kube::util::wait_for_url() {
 kube::util::ensure-temp-dir() {
   if [[ -z ${KUBE_TEMP-} ]]; then
     KUBE_TEMP=$(mktemp -d 2>/dev/null || mktemp -d -t kubernetes.XXXXXX)
+    kube::util::trap_add kube::util::cleanup-temp-dir EXIT
   fi
 }
 

hack/test-cmd.sh

@@ -74,8 +74,7 @@ function check-curl-proxy-code()
   echo "For address ${full_address}, got ${status} but wanted ${desired}"
   return 1
 }
-
-trap cleanup EXIT SIGINT
+kube::util::trap_add cleanup EXIT SIGINT
 
 kube::util::ensure-temp-dir
 kube::etcd::start