idem_apt_install

install.sh

@@ -1,40 +1,33 @@
 #!/bin/bash
 
-
 BASEDIR=$PWD
-TAG=$(cat /opt/debian-bash/.semver_git_tag)
+REQUIRED_PKGS=(jq rsync file git)
 
-function usage {
+function usage() {
     echo 'usage: --host | --containers | --full | --one-container <CT_NAME>'
     exit -1
 }
 
-function install_host {
+function install_host() {
     echo "install on: $HOSTNAME"
     echo ----------------------
 
-    [ `id -u` -ne 0 ] && echo 'root privilege required' && exit 1
-
-	# required packages jq
-	/usr/bin/dpkg-query --status jq >/dev/null 2>&1
-	[ $? -ne 0 ] && /usr/bin/apt install -y jq
-
-	# required packages rsync
-	/usr/bin/dpkg-query --status rsync >/dev/null 2>&1
-	[ $? -ne 0 ] && /usr/bin/apt install -y rsync
+    [ $(id -u) -ne 0 ] && echo 'root privilege required' && exit 1
 
+    # shellcheck disable=SC1091
+    source "$BASEDIR/lib/functions.sh"
+    idem_apt_install "${REQUIRED_PKGS[@]}"
 
     if [[ ! $BASEDIR == '/opt/debian-bash' ]]; then
         # download and filfull /opt/debian-bash, then run it from folder
 
         if [[ -L /opt/debian-bash ]]; then
-			cd /opt/debian-bash
-			./install.sh $PARAM1
+            cd /opt/debian-bash && ./install.sh "$PARAM1"
             exit 0
         else
 
             rm -rf /opt/debian-bash
-	        TEMP=`mktemp -d`
+            TEMP=$(mktemp -d)
             cd $TEMP
             echo $TEMP
             wget https://git.artcode.re/pvincent/debian-bash/archive/master.tar.gz
@@ -56,8 +49,7 @@ function install_host {
         ORIGINAL="ORIGINAL"
         declare -a arr=(/etc/bash.bashrc /etc/inputrc /etc/vim/vimrc)
 
-        for i in "${arr[@]}"
-        do
+        for i in "${arr[@]}"; do
             if [ ! -f "$i.$ORIGINAL" ]; then
 
                 echo "$i needs installation $(basename $i)"
@@ -71,13 +63,13 @@ function install_host {
     fi
 }
 
-function install_containers {
+function install_containers() {
     echo "install containers"
     echo --------------------
 
     # install inside active LXC containers
     if [[ -f '/snap/bin/lxc' ]]; then
-        for container in `/snap/bin/lxc list --format=json | /bin/jq -r '.[] | select(.state.status == "Running") | .name'`; do
+        for container in $(/snap/bin/lxc list --format=json | /bin/jq -r '.[] | select(.state.status == "Running") | .name'); do
             install_one_container $container
             echo
         done
@@ -85,7 +77,7 @@ function install_containers {
 
 }
 
-function install_one_container {
+function install_one_container() {
     CT=$1
     echo "install container <$CT>"
     echo -------------------------
@@ -122,5 +114,3 @@ case $PARAM1 in
     usage
     ;;
 esac
-
-

lib/functions.sh

@@ -1,3 +1,11 @@
+# idempotent apt install [package1 package2 ...]
+function idem_apt_install() {
+  for i in $@; do
+    if ! (/usr/bin/dpkg-query --status "$i" >/dev/null 2>&1); then
+      /usr/bin/apt install -y "$i"
+    fi
+  done
+}
 
 ##
 # return 0 (true) if array (passed by name) contains element
@@ -9,18 +17,18 @@ containsElement () {
   if $(isArray $1); then
     for index in ${arraykeys[*]}; do
       current=$1"[$index]"
-		  [[ "${!current}" == "$2" ]] && return 0; # found
+      [[ "${!current}" == "$2" ]] && return 0 # found
     done
-	  return 1; # not found
+    return 1 # not found
   else
-    >&2 echo "ERROR: $1 not an array!" 
-    return 2; # not an array
+    echo >&2 "ERROR: $1 not an array!"
+    return 2 # not an array
   fi
 }
 
 isArray() {
-  [[ "$(declare -p $1 2> /dev/null)" =~ "declare -a" ]] && return 0; # is an array
-  return 1; # not an array
+  [[ "$(declare -p $1 2>/dev/null)" =~ "declare -a" ]] && return 0 # is an array
+  return 1                                                         # not an array
 }
 
 ##