A small script to check if Nirila Misskey is healthy, and send alert to a discord webhook if it's not.

healthcheck.sh

#!/bin/sh
# A small script to check if Nirila Misskey is healthy, and send alert to a discord webhook if it's not.
#
# Optionally, you can send webhook even if it's healthy to confirm that the script is working.
#
# This script is depending on /healthz endpoint of Misskey added in 2024.5.0 so your Misskey must be at least that version.
#
# This script is Published at https://gist.github.com/anatawa12/95dfcbe21271bbc6b6ad58398f2ba284.
# You may get the latest version from there.
#
# Usage:
# 1. Copy this script to your server. you can clone the repository, or just download file with wget or curl.
#    For getting directly you can download from the URL:
#      wget https://gist.githubusercontent.com/anatawa12/95dfcbe21271bbc6b6ad58398f2ba284/raw/healthcheck.sh
#      curl -O https://gist.githubusercontent.com/anatawa12/95dfcbe21271bbc6b6ad58398f2ba284/raw/healthcheck.sh
# 2. Edit the .env file to set the SERVER and WEBHOOK_URL. If you want to send webhook even if it's healthy, set SEND_ALWAYS to true.
# 3. Configure a cron job to run this script periodically.
#
# Configurations:
# required:
# - SERVER: The domain of your Misskey instance. This may include protocol, port, and trailing slash if needed. If no protocol is provided, https will be used.
#           EXAMPLES:
#	          - SERVER=example.com                 - equivalent to https://example.com/
#	          - SERVER=example.com/                - equivalent to https://example.com/
#	          - SERVER=http://example.com          - equivalent to http://example.com/
#	          - SERVER=https://example.com         - equivalent to https://example.com/
#	          - SERVER=https://example.com/        - equivalent to https://example.com/
#	          - SERVER=https://example.com:3000/   - equivalent to https://example.com:3000/
# - WEBHOOK_URL: The URL of the Discord webhook to send the alert to.
# optional:
# - LOG: If set to false, the script will not log anything except errors.
#        If set to true, the script will log the message to stderr.
#        Default is true.
# - SEND_ALWAYS: If set to true, the script will send message to the webhook even if the server is healthy.
#                Default is false.
# - MENTIONS: If set, the script will mention the specified users in the message if the server is unhealthy.
#             EXAMPLES:
#             - MENTIONS="<@1234567890>"                 - mentions user with ID 1234567890
#             - MENTIONS="<@&1234567890>"                - mentions role with ID 1234567890
#             - MENTIONS="<@1234567890> <@&1234567890>"  - mentions user and role
#
# License: MIT License
# MIT License
#
# Copyright (c) 2025 anatawa12
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in all
# copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
# SOFTWARE.

# start of the program

# load .env
. "$(dirname "$0")/.env"

# check if SERVER and WEBHOOK_URL are set
if [ -z "$SERVER" ] || [ -z "$WEBHOOK_URL" ]; then
	echo "SERVER and WEBHOOK_URL must be set in .env" >&2
	exit 1
fi

# check if required commands are available
check_command() {
	if ! command -v "$1" > /dev/null; then
		echo "$1 is required but not found" >&2
		exit 1
	fi
}
check_command curl
check_command jq

# normalize SERVER
# if no protocol is provided, use https
if [ "${SERVER%%://*}" = "$SERVER" ]; then
	SERVER="https://$SERVER"
fi
# remove trailing slash
SERVER=${SERVER%/}

# log utility: if $LOG is not 'false', log the message to stdout
if [ "$LOG" != "false" ]; then
	log() {
		echo "$(date -u +"%Y-%m-%dT%H:%M:%SZ") $1" >&2
	}
else
	log() {
		:
	}
fi

send_message() {
	jq -n -R --arg MESSAGE "$1" '{"content": $MESSAGE}' \
		| curl --header "Content-Type: application/json" --request POST --data @- "$WEBHOOK_URL"
}

if curl --show-error --fail --silent --output /dev/null "$SERVER/healthz"; then
	log "Misskey is healthy"
	if [ "$SEND_ALWAYS" = "true" ]; then
		send_message "Misskey at <$SERVER/> is healthy."
	fi
else
	log "Misskey is unhealthy. Sending alert webhook..."
	send_message "$MENTIONS Misskey at <$SERVER/> is NOT healthy. Please check the server."
fi