fix: Simplify healthcheck

#!/usr/bin/env bash

set -Eeuo pipefail

file="/run/dsm.url"

active="/run/qemu.pid"

shutdown="/run/qemu.count"

url="http://127.0.0.1:2210/read?command=10"

active_msg="QEMU not running yet.."

shutdown_msg="QEMU is shutting down.."

resp_err="Guest returned an invalid response:"

jq_err="Failed to parse response from guest: jq error"

[ ! -f "$active" ] && echo "$active_msg" && exit 0

[ -f "$shutdown" ] && echo "$shutdown_msg" && exit 1

if [ ! -f  "$file" ]; then

[ ! -f "/run/qemu.pid" ] && echo "QEMU not running yet.." && exit 0

[ -f "/run/qemu.count" ] && echo "QEMU is shutting down.." && exit 1

  # Retrieve IP from guest VM for Docker healthcheck

  { json=$(curl -m 20 -sk "$url"); rc=$?; } || :

  [ -f "$shutdown" ] && echo "$shutdown_msg" && exit 1

  (( rc != 0 )) && echo "Failed to connect to guest: curl error $rc" && exit 1

  { result=$(echo "$json" | jq -r '.status'); rc=$?; } || :

  (( rc != 0 )) && echo "$jq_err $rc ( $json )" && exit 1

  [[ "$result" == "null" ]] && echo "$resp_err $json" && exit 1

  if [[ "$result" != "success" ]] ; then

    { msg=$(echo "$json" | jq -r '.message'); rc=$?; } || :

    echo "Guest replied $result: $msg" && exit 1

  fi

  { port=$(echo "$json" | jq -r '.data.data.dsm_setting.data.http_port'); rc=$?; } || :

  (( rc != 0 )) && echo "$jq_err $rc ( $json )" && exit 1

  [[ "$port" == "null" ]] && echo "$resp_err $json" && exit 1

  [ -z "$port" ] && echo "Guest has not set a portnumber yet.." && exit 1

  { ip=$(echo "$json" | jq -r '.data.data.ip.data[] | select((.name=="eth0") and has("ip")).ip'); rc=$?; } || :

  (( rc != 0 )) && echo "$jq_err $rc ( $json )" && exit 1

  [[ "$ip" == "null" ]] && echo "$resp_err $json" && exit 1

  [ -z "$ip" ] && echo "Guest has not received an IP yet.." && exit 1

  echo "$ip:$port" > $file

fi

[ -f "$shutdown" ] && echo "$shutdown_msg" && exit 1

file="/run/dsm.url"

[ ! -f  "$file" ] && echo "DSM has not enabled networking yet.." && exit 1

location=$(cat "$file")

if ! curl -m 20 -ILfSs "http://$location/" > /dev/null; then

  [ -f "$shutdown" ] && echo "$shutdown_msg" && exit 1

  echo "Failed to reach page at http://$location" && exit 1

fi