commands

#!/usr/bin/env bash

set -eo pipefail; [[ $DOKKU_TRACE ]] && set -x
source "$PLUGIN_CORE_AVAILABLE_PATH/common/functions"

DOKKU_NODEEXPORTER_IMAGE="prom/node-exporter:v0.15.2"
DOKKU_NODEEXPORTER_CONTAINER=nodeexporter
DOKKU_NODEEXPORTER_DEFAULT_PORT=9100
DOKKU_NODEEXPORTER_PORT="${DOKKU_NODEEXPORTER_PORT:-$DOKKU_NODEEXPORTER_DEFAULT_PORT}"
DOKKU_NODEEXPORTER_ARGS="--path.procfs=/host/proc --path.sysfs=/host/sys --collector.filesystem.ignored-mount-points=^/(sys|proc|dev|host|etc)($|/)"

f_check_container() {
  local l_status

  l_status="$(docker inspect -f '{{.State.Running}}' $DOKKU_NODEEXPORTER_CONTAINER 2>/dev/null)" || l_status=none
  printf "%s" "$l_status"
}

# Start the container
f_dokku_nodeexporter_start() {
  case $(f_check_container) in
    none)
      echo "Starting nodeexporter on port ${DOKKU_NODEEXPORTER_PORT} ..."
      docker run \
        --user root \
        --privileged \
        --volume=/proc:/host/proc:ro \
        --volume=/sys:/host/sys:ro \
        --volume=/:/rootfs:ro \
        --publish="$DOKKU_NODEEXPORTER_PORT:9100" \
        --detach=true \
        --name="$DOKKU_NODEEXPORTER_CONTAINER" \
        $DOKKU_NODEEXPORTER_IMAGE \
        $DOKKU_NODEEXPORTER_ARGS \
        > /dev/null
      ;;
    false)
      echo "Starting nodeexporter on port ${DOKKU_NODEEXPORTER_PORT} ..."
      docker start "$DOKKU_NODEEXPORTER_CONTAINER" >/dev/null
      ;;
    *)
      echo "nodeexporter is already running"
      ;;
  esac
}


# Stop the container
f_dokku_nodeexporter_stop() {
  case $(f_check_container) in
    true)
      echo "Stopping nodeexporter ..."
      docker stop "$DOKKU_NODEEXPORTER_CONTAINER" >/dev/null
      ;;
    *)
      echo "nodeexporter is not running"
      ;;
  esac
}

# Pull nodeexporter image
f_dokku_nodeexporter_install() {
  docker pull "$DOKKU_NODEEXPORTER_IMAGE" >/dev/null
  case $(f_check_container) in
    true)
      f_dokku_nodeexporter_start
      docker rm "$DOKKU_NODEEXPORTER_CONTAINER" >/dev/null
      f_dokku_nodeexporter_stop
      ;;
    false)
      docker rm "$DOKKU_NODEEXPORTER_CONTAINER" >/dev/null
      ;;
    *) ;;
  esac
}

case "$1" in
  nodeexporter)
    case $(f_check_container) in
      true)
        echo "nodeexporter is running on http://$(hostname -f):${DOKKU_NODEEXPORTER_PORT}/" ;;
      *)
        echo "nodeexporter is not running" ;;
    esac ;;

  nodeexporter:start)
    f_dokku_nodeexporter_start ;;

  nodeexporter:stop)
    f_dokku_nodeexporter_stop ;;

  nodeexporter:install)
    f_dokku_nodeexporter_install ;;

  help | nodeexporter:help)
    cat<<EOF
    nodeexporter, Show the status of nodeexporter
    nodeexporter:start, Start nodeexporter service
    nodeexporter:stop, Stop nodeexporter
EOF
    ;;

  *)
    exit "$DOKKU_NOT_IMPLEMENTED_EXIT"
    ;;
esac