commit 6d4437efb62aa86d96c217298f41aeaf6f1f39d7
Author: Benjamin Renard <brenard@zionetrix.net>
Date:   Sun Mar 3 17:18:20 2024 +0100

    Initial version

diff --git a/README.md b/README.md
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index 0000000..4fde042
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+++ b/README.md
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+# Check container upgrade
+
+Monitoring plugin to check if containers are upgradable. By default all running container are checked.
+
+Check are done by running Icinga/Nagios compatible check plugin inside containers.
+
+## Installation
+
+```
+git clone https://gitea.zionetrix.net/bn8/check_container_upgrade.git /usr/local/src/check_container_upgrade
+mkdir -p /usr/local/lib/nagios/plugins
+ln -s /usr/local/src/check_container_upgrade/check_container_upgrade /usr/local/lib/nagios/plugins/
+echo "nagios ALL=NOPASSWD: /usr/local/lib/nagios/plugins/check_container_upgrade" > /etc/sudoers.d/nagios-containers
+chmod 0400 /etc/sudoers.d/nagios-containers
+echo "command[check_container_upgrade]=sudo /usr/local/lib/nagios/plugins/check_container_upgrade" > /etc/nagios/nrpe.d/containers.cfg
+service nagios-nrpe-server reload
+```
+
+## Usage
+
+```
+Usage : check_container_upgrade [-d] [-E /path/to/engine] [container1,...]
+	-E [path]               Force a specific engine (possible values: auto docker podman, default: auto)
+	-x [container]		Exclude specified container (could be repeat)
+	-d			Debug mode
+	-X			Enable bash tracing (=set -x)
+	-h 			Show this message
+```
+
+## Copyright
+
+Copyright (c) 2024 Benjamin Renard <brenard@zionetrix.net>
+
+## License
+
+This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License version 3 as published by the Free Software Foundation.
+
+This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
diff --git a/check_container_upgrade b/check_container_upgrade
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+++ b/check_container_upgrade
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+#!/bin/bash
+# Monitoring plugin to check if running containers are upgradable
+# 
+# Author: Benjamin Renard <brenard@zionetrix.net>
+# Date: Sun, 03 Mar 2024 16:40:19 +0100
+# Source: https://gitea.zionetrix.net/bn8/check_container_upgrade
+#
+
+ENGINE="auto"
+POSSIBLE_ENGINES=( "auto" "docker" "podman" )
+DEBUG=0
+EXCLUDED_CONTAINERS=( buildx_buildkit_default )
+declare -rA CHECK_PLUGINS=(
+	["/usr/lib/nagios/plugins/check_apt"]="/usr/lib/nagios/plugins/check_apt -u -U -t 60 -l"
+	["/usr/lib/nagios/plugins/check_apk"]="/usr/lib/nagios/plugins/check_apk"
+)
+
+function debug() {
+	if [ $DEBUG -eq 1 ]
+	then
+		>&2 echo -e "[DEBUG] $1"
+	fi
+}
+
+function is_empty() {
+	[ $# -gt 0 ] && return 1
+	return 0
+}
+
+function in_array() {
+	param=$1;
+	shift;
+	for elem in "$@";
+	do
+	    [[ "$param" = "$elem" ]] && return 0;
+	done;
+	return 1
+}
+
+function usage() {
+	error="$1"
+	[ -n "$error" ] && echo "$error"
+	cat << EOF
+Usage : $0 [-d] [-E /path/to/engine] [container1,...]
+	-E [path]               Force a specific engine (possible values: ${POSSIBLE_ENGINES[@]}, default: $ENGINE)
+	-x [container]		Exclude specified container (could be repeat)
+	-d			Debug mode
+	-X			Enable bash tracing (=set -x)
+	-h 			Show this message
+EOF
+	[ -n "$error" ] && exit 1
+	exit 0
+}
+
+while getopts "hdXE:x:" OPTION
+do
+	case $OPTION in
+		d)
+			DEBUG=1
+		;;
+		h)
+			usage
+		;;
+		E)
+			ENGINE=$OPTARG
+			if [ ! -x "$ENGINE" ]
+			then
+				in_array $ENGINE $POSSIBLE_ENGINES || usage "Invalid engine $ENGINE"
+			fi
+		;;
+		x)
+			EXCLUDED_CONTAINERS+=( $OPTARG )
+		;;
+		X)
+			set -x
+		;;
+		*)
+			usage "Unknown option $OPTION"
+		;;
+	esac
+done
+ONLY_CONTAINERS=( "${@:$OPTIND}" )
+! is_empty $ONLY_CONTAINERS && debug "Only containers: ${ONLY_CONTAINERS[@]}"
+
+if [ "$ENGINE" == "auto" ]
+then
+	debug "Auto-detect engine..."
+	for engine in ${POSSIBLE_ENGINES[@]}
+	do
+		[ "$engine" == "auto" ] && continue
+		which "$engine" > /dev/null 2>&1
+		if [ $? -ne 0 ]
+		then
+			debug "$engine not found"
+			continue
+		fi
+		ENGINE="$engine"
+		break
+	done
+	if [ -z "$ENGINE" ]
+	then
+		echo "UNKNOWN - Fail to auto-detect engine"
+		exit 3
+	fi
+	debug "Auto-detected engine: $ENGINE"
+fi
+
+EXIT_CODE=0
+declare -A UPTODATE
+declare -A ERRORS
+CHECKED_CONTAINERS=( )
+
+debug "List running containers..."
+RUNNING_CONTAINERS=$($ENGINE ps --format '{{.Names}}' | tr '\n' ' ')
+debug "Running containers: $RUNNING_CONTAINERS"
+
+for container in $RUNNING_CONTAINERS
+do
+	if ! is_empty $ONLY_CONTAINERS && ! in_array $container $ONLY_CONTAINERS
+	then
+		debug "$container - Ignored"
+		continue
+	fi
+	if in_array $container $EXCLUDED_CONTAINERS
+	then
+		debug "$container - Excluded"
+		continue
+	fi
+	CHECKED_CONTAINERS+=( "$container" )
+	STATUS=""
+	for check_plugin in ${CHECK_PLUGINS[@]}
+	do
+		$ENGINE exec $container test -e $check_plugin > /dev/null 2>&1
+		if [ $? -ne 0 ]
+		then
+			debug "$container - Plugin $check_plugin not found"
+			continue
+		fi
+		debug "$container - Plugin $check_plugin found, use it"
+		STATUS="$($ENGINE exec $container ${CHECK_PLUGINS[${check_plugin}]} 2>&1)"
+		ex=$?
+		debug "$container - Plugin output: $STATUS"
+		debug "$container - Plugin exit code: $ex"
+		break
+	done
+	if [ -z "$STATUS" ]
+	then
+		debug "$container - No check plugin found"
+		STATUS="UNKNOWN - No check plugin available"
+		ex=3
+	fi
+	if [ $ex -eq 0 ]
+	then
+		UPTODATE+=( ["$container"]=$STATUS )
+	else
+		ERRORS+=( ["$container"]=$STATUS )
+	fi
+	[ $EXIT_CODE -ge $ex ] && continue
+	[ $ex -gt 3 ] && ex=3
+	EXIT_CODE=$ex
+done
+
+if ! is_empty $ONLY_CONTAINERS
+then
+	for container in ${ONLY_CONTAINERS[@]}
+	do
+		if ! in_array $container $CHECKED_CONTAINERS
+		then
+			debug "$container - Not found"
+			ERRORS+=( ["$container"]="Not found" )
+			EXIT_CODE=3
+		fi
+	done
+fi
+
+debug "Final exit code: $EXIT_CODE"
+
+case $EXIT_CODE in
+	0)
+		echo "OK - All containers are uptodate"
+		;;
+	1)
+		echo "WARNING - some containers need to be updated"
+		;;
+	2)
+		echo "CRITICAL - some containers need to be updated"
+		;;
+	*)
+		echo "UNKNOWN - fail to retrieve status of some containers"
+		;;
+esac
+for container in ${!ERRORS[@]}
+do
+    echo ${container} - ${ERRORS[${container}]}
+done
+
+for container in ${!UPTODATE[@]}
+do
+    echo ${container} - ${UPTODATE[${container}]}
+done
+
+exit $EXIT_CODE