[Update] added --force mode to update skript (#3453)

update.sh

@@ -88,18 +88,21 @@ docker_garbage() {
     echo
     echo "    docker rmi ${IMGS_TO_DELETE[*]}"
     echo
+    if [ ! $FORCE ]; then
       read -r -p "Do you want to delete old image tags right now? [y/N] " response
       if [[ "$response" =~ ^([yY][eE][sS]|[yY])+$ ]]; then
         docker rmi ${IMGS_TO_DELETE[*]}
       else
         echo "OK, skipped."
       fi
+    else
+      echo "Skipped image removal because of force mode."
+    fi
   fi
   echo -e "\e[32mFurther cleanup...\e[0m"
   echo "If you want to cleanup further garbage collected by Docker, please make sure all containers are up and running before cleaning your system by executing \"docker system prune\""
 }
 
-
 while (($#)); do
   case "${1}" in
     --check|-c)
@@ -133,6 +136,10 @@ while (($#)); do
       prefetch_images
       exit 0
     ;;
+    -f|--force)
+      echo -e "\e[32mForcing Update...\e[0m"
+      FORCE=y
+    ;;
     --help|-h)
     echo './update.sh [-c|--check, --ours, --gc, --skip-start, -h|--help]
 
@@ -140,6 +147,7 @@ while (($#)); do
   --ours       -   Use merge strategy "ours" to solve conflicts in favor of non-mailcow code (local changes)
   --gc         -   Run garbage collector to delete old image tags
   --skip-start -   Do not start mailcow after update
+  -f|--force   -   Force update, do not ask questions
 '
     exit 1
   esac
@@ -356,7 +364,7 @@ SHA1_2=$(sha1sum update.sh)
 if [[ ${SHA1_1} != ${SHA1_2} ]]; then
   echo "update.sh changed, please run this script again, exiting."
   chmod +x update.sh
-  exit 0
+  exit 2
 fi
 
 if [[ -f mailcow.conf ]]; then
@@ -366,11 +374,13 @@ else
   exit 1
 fi
 
+if [ ! $FORCE ]; then
   read -r -p "Are you sure you want to update mailcow: dockerized? All containers will be stopped. [y/N] " response
   if [[ ! "$response" =~ ^([yY][eE][sS]|[yY])+$ ]]; then
     echo "OK, exiting."
     exit 0
   fi
+fi
 
 echo -e "\e[32mValidating docker-compose stack configuration...\e[0m"
 if ! docker-compose config -q; then