Add support for --app flag. Refs #1638

This change sets a DOKKU_APP_NAME env var, which can be used by plugins as a replacement for the `app` param if specified. Note that each plugin will have to manually shift it's arguments if necessary

dokku

@@ -47,7 +47,9 @@ parse_args "$@"
 args=("$@")
 if [[ "${args[0]}" =~ ^--.* ]]; then
   for arg in "$@"; do
-    if [[ "$arg" =~ ^--.* ]]; then
+    if [[ "$arg" == "--app" ]]; then
+      shift 2
+    elif [[ "$arg" =~ ^--.* ]]; then
       shift 1
     else
       break

plugins/common/functions

@@ -196,7 +196,9 @@ is_abs_path() {
 }
 
 parse_args() {
+  local next_index=1; local skip=false; local args=("$@")
   for arg in "$@"; do
+    $skip && skip=false && continue
     case "$arg" in
       --quiet)
         export DOKKU_QUIET_OUTPUT=1
@@ -210,7 +212,11 @@ parse_args() {
       --force)
         export DOKKU_APPS_FORCE_DELETE=1
         ;;
+      --app)
+        export DOKKU_APP_NAME=${args[$next_index]}; skip=true
+        ;;
     esac
+    next_index=$(( next_index + 1 ))
   done
   return 0
 }