refactor: standardize help generation

plugins/domains/help-functions

@@ -0,0 +1,43 @@
+#!/usr/bin/env bash
+set -eo pipefail
+[[ $DOKKU_TRACE ]] && set -x
+
+cmd-domains-help() {
+  declare desc="help command"
+  declare CMD="$1"
+  local plugin_name="domains"
+  local plugin_description="Manage domains used by the proxy"
+
+  if [[ "$CMD" == "$plugin_name:help" ]]; then
+    echo -e "Usage: dokku $plugin_name[:COMMAND]"
+    echo ''
+    echo "$plugin_description"
+    echo ''
+    echo 'Additional commands:'
+    fn-help-content | sort | column -c2 -t -s,
+  elif [[ $(ps -o command= $PPID) == *"--all"* ]]; then
+    fn-help-content
+  else
+    cat <<help_desc
+    $plugin_name, $plugin_description
+help_desc
+  fi
+}
+
+fn-help-content() {
+  declare desc="return help content"
+  cat <<help_content
+    domains [<app>], [DEPRECATED] Alternative for domains:report
+    domains:add <app> <domain> [<domain> ...], Add domains to app
+    domains:add-global <domain> [<domain> ...], Add global domain names
+    domains:clear <app>, Clear all domains for app
+    domains:clear-global, Clear global domain names
+    domains:disable <app>, Disable VHOST support
+    domains:enable <app>, Enable VHOST support
+    domains:remove <app> <domain> [<domain> ...], Remove domains from app
+    domains:remove-global <domain> [<domain> ...], Remove global domain names
+    domains:report [<app>|--global] [<flag>], Displays a domains report for one or more apps
+    domains:set <app> <domain> [<domain> ...], Set domains for app
+    domains:set-global <domain> [<domain> ...], Set global domain names
+help_content
+}