syno_docker_switch_logger.sh

#!/bin/sh


terminate() {
    printf "${RED}${BOLD}%s${NC}\n" "ERROR: $1"
	echo
    exit 1
}

usage() {
    echo "Usage: (as root) $0 [PATH_TO_DOCKERD.JSON]"
    echo
    echo "This script will modify the logger in the dockerd.json file to 'local'"
    echo
}

readonly RED='\e[31m' # Red color
readonly NC='\e[m' # No color / reset
readonly BOLD='\e[1m' # Bold font
DOCKERD_FILE=$1

# Test if script has root privileges, exit otherwise
id=$(id -u)
if [ "${id}" -ne 0 ]; then
	usage
	terminate "You need to be root to run this script"
fi

# Check if the dockerd.json file path is provided as an argument
if [ -z "$1" ]; then
	usage
	terminate "no path to dockerd.json provided"
fi

# Check if dockerd.json file exists
if [ ! -f "${DOCKERD_FILE}" ]; then
	usage
	terminate "no dockerd.json found at provided location"
fi

# Output the original JSON file
echo "Original dockerd.json file:"
echo "----------------------------"
echo
jq < ${DOCKERD_FILE}  
echo

# Use jq to safely update the log-driver and merge new log-opts

# add iptables=true
#jq '
#  .["group"] = "administrators" |
#  .["log-driver"] = "local" |
#  .["log-opts"] = {
#    "max-file": "5",
#    "max-size": "20m"
#  } |
#  .["iptables"] = true
#' "$DOCKERD_FILE" > "$DOCKERD_FILE.tmp" && mv "$DOCKERD_FILE.tmp" "$DOCKERD_FILE"

jq '
  .["group"] = "administrators" |
  .["log-driver"] = "local" |
  .["log-opts"] = {
    "max-file": "5",
    "max-size": "20m"
  } 
' "$DOCKERD_FILE" > "$DOCKERD_FILE.tmp" && mv "$DOCKERD_FILE.tmp" "$DOCKERD_FILE"

# Output the new JSON file
echo "Updated dockerd.json file:"
echo "----------------------------"
echo
jq < ${DOCKERD_FILE}
echo

exit 0