Docker container healthcheck and automatic restart based on Uptime Kuma monitor name in metrics endpoint.

healthcheck.sh

#!/bin/bash

# docker-compose example:
#version: "3.9"
#services:
#  qbittorrent:
#    image: lscr.io/linuxserver/qbittorrent:latest
#    environment:
#      - UPTIME_KUMA_API_KEY=your_api_key
#    volumes:
#      - ./healthcheck.sh:/scripts/healthcheck.sh
#    healthcheck:
#      test: [ "CMD", "/bin/bash", "/scripts/healthcheck.sh", "http://uptime-kuma:3001", "qBittorrent" ]
#      interval: 10s
#      timeout: 10s
#      retries: 3

if [ $# -ne 2 ]; then
  echo "Usage: $0 <UPTIME_KUMA_URL> <MONITOR_NAME>"
  exit 1
fi

if [ -z "$UPTIME_KUMA_API_KEY" ]; then
  echo "Environment variable <UPTIME_KUMA_API_KEY> is not set."
  exit 1
fi

UPTIME_KUMA_URL=$1
MONITOR_NAME=$2

# Make http request and find specific monitor status.
RESPONSE=$(curl -su ":${UPTIME_KUMA_API_KEY}" "$UPTIME_KUMA_URL/metrics" | grep "monitor_status{monitor_name=\"${MONITOR_NAME}\"")

# Extract status (1 = UP, 0 = DOWN, 2 = PENDING, 3 = MAINTENANCE)
STATUS="${RESPONSE: -1}"

# Down/Pending/Maintenance
if [[ $STATUS != "1" ]]; then
  echo "Healthcheck FAILED"
  
  # Send signal to kill process.
  kill 1
  exit 1
fi

# UP
echo "Healthcheck OK"
exit 0