diff --git a/plugin.sh b/plugin.sh
index 165d2d6..bc746de 100755
--- a/plugin.sh
+++ b/plugin.sh
@@ -63,14 +63,15 @@ fi
 # support format Major.Minor.Release or start with `v`
 # docker tags: Major, Major.Minor, Major.Minor.Release and latest
 if [[ "${PLUGIN_AUTO_TAG:-}" == "true" ]]; then
-	TAG=$(echo "${CI_COMMIT_TAG:-}" |sed 's/^v//g')
-	tag_part_count=$(echo "${TAG}" | tr '.' '\n' |wc -l)
+	TAG=$(echo "${CI_COMMIT_TAG:-}" | sed 's/^v//g')
+	tag_part_count=$(echo "${TAG}" | tr '.' '\n' | wc -l)
+	tag_field=${PLUGIN_:-major}
 	# expect number
-	echo ${TAG} | grep -E "[a-z-]" &>/dev/null && isNum=1 || isNum=0
+	echo ${TAG} | grep -E "[a-z-]" &>/dev/null && tag_contains_letter=1 || tag_contains_letter=0
 
 	if [ ! -n "${TAG:-}" ]; then
 		echo "latest" > .tags
-	elif [ ${isNum} -eq 1 -o ${tag_part_count} -gt 3 ]; then
+	elif [ ${tag_contains_letter} -eq 1 -o ${tag_part_count} -gt 3 ]; then
 		echo "${TAG},latest" > .tags
 	else
 		major=$(echo "${TAG}" | awk -F'.' '{print $1}')
@@ -97,18 +98,18 @@ else
 	CACHE=""
 fi
 
-COMMAND=$(cat <<-EOF
-/kaniko/executor -v ${LOG} \
-	--context=${CONTEXT} \
-	--dockerfile=${DOCKERFILE} \
-	${EXTRA_OPTS} \
-	${DESTINATIONS} \
-	${CACHE:-} \
-	${CACHE_TTL:-} \
-	${CACHE_REPO:-} \
-	${TARGET:-} \
-	${BUILD_ARGS:-} \
-	${BUILD_ARGS_FROM_ENV:-}"
+COMMAND=$(tr -d "\n" <<-EOF
+/kaniko/executor -v ${LOG} 
+	--context=${CONTEXT} 
+	--dockerfile=${DOCKERFILE} 
+	${EXTRA_OPTS} 
+	${DESTINATIONS} 
+	${CACHE:-} 
+	${CACHE_TTL:-} 
+	${CACHE_REPO:-} 
+	${TARGET:-} 
+	${BUILD_ARGS:-} 
+	${BUILD_ARGS_FROM_ENV:-}
 EOF
 )