#! /bin/sh
#
# Check Asterisk ODBC connections plugin for Nagios.
# Written by Chad Phillips (chad@apartmentlines.com)
# Last Modified: 2009-02-28

ASTERISK=/usr/sbin/asterisk

PROGPATH=`dirname $0`
REVISION=`echo '$Revision: 1 $' | sed -e 's/[^0-9.]//g'`

. $PROGPATH/utils.sh

print_usage() {
    echo "
Usage: check_asterisk_odbc_connections [--databases | -d <databases>] [-V]
Usage: check_asterisk_odbc_connections --help | -h

Description:

This plugin tests the connectivity of ODBC databases configured via Asterisk's
res_odbc.conf file.  

Tested to work on Linux.

The following arguments are accepted:

  --databases | -d  (Optional) A space separated list of ODBC databases to
                    check.  The names are the section names of the databases
                    listed in the res_odbc.conf Asterisk configuration file.
                    If this option is left out, then all configured databases
                    will be checked.

  -V                (Optional) Output verbose information, useful for 
                    debugging.

  --help | -h       Print this help and exit.

Examples:

Check all configured Asterisk ODBC databases:

  check_asterisk_odbc_connections

Check the 'foo' and 'bar' connections:

  check_asterisk_odbc_connections \"foo bar\"


Caveats:

This plugin calls the asterisk executable directly, so make sure that the user
executing this script has appropriate permissions!  Usually the asterisk binary
can only be run by the asterisk user or root. To grant the nagios user
permissions to execute the script, try something like the following in your
/etc/sudoers file:
  nagios ALL=(ALL) NOPASSWD: /path/to/plugins/directory/check_asterisk_odbc_connections

Then call the plugin using sudo:
  /path/to/sudo check_asterisk_odbc_connections
"
}

print_help() {
    print_usage
    echo "Check Asterisk ODBC connections plugin for Nagios."
    echo ""
}

# Sets the exit status for the plugin.  This is done in such a way that the
# status can only go in one direction: OK -> WARNING -> CRITICAL.
set_exit_status() {
	new_status=$1
	# Nothing needs to be done if the state is already critical, so exclude
	# that case.
	case $exitstatus
	in
		$STATE_WARNING)
			# Only upgrade from warning to critical.
			if [ "$new_status" = "$STATE_CRITICAL" ]; then
				exitstatus=$new_status;
			fi
		;;
		$STATE_OK)
			# Always update state if current state is OK.
			exitstatus=$new_status;
		;;
	esac
}

# Ensures that a call to the Asterisk process returns successfully.  Exits
# critical if not.
check_asterisk_result() {
	if [ "$1" != "0" ]; then
		echo "CRITICAL: $2"
		exit $STATE_CRITICAL
	fi
}

# Defaults.
exitstatus=$STATE_OK
verbose=
output=
test_errors=
test_ok=
databases=

# Grab the command line arguments.
while test -n "$1"; do
    case "$1" in
        --help)
            print_help
            exit $STATE_OK
            ;;
        -h)
            print_help
            exit $STATE_OK
            ;;
        --databases)
            databases=$2
            shift
            ;;
        -d)
            databases=$2
            shift
            ;;
		-V)
			verbose=1
            ;;
        -x)
            exitstatus=$2
            shift
            ;;
        --exitstatus)
            exitstatus=$2
            shift
            ;;
        *)
            echo "Unknown argument: $1"
            print_usage
            exit $STATE_UNKNOWN
            ;;
    esac
    shift
done

# If no databases were provided, then check all configured databases.
if [ ! "$databases" ]; then
	command_output=`$ASTERISK -rx "odbc show" 2>&1`
	check_asterisk_result $? "$command_output"
	databases=`echo "$command_output" | grep ^Name: | cut -d " " -f 2`
fi

# Check each database.
for db in $databases
do
	if [ "$db" ]; then
		# Test asterisk recognition of ODBC connection.
		command_output=`$ASTERISK -rx "odbc show $db" 2>&1`
		check_asterisk_result $? "$command_output"
		if [ "$verbose" ]; then
			echo "Checking ${db}:"
			echo "$command_output"
			echo ""
		fi
		
		# Check the status of the connection.
		status_yes=`echo "$command_output" | grep "^Connected: yes$"`
		if [ "$status_yes" ]; then
			if [ "$test_ok" ]; then
				test_ok="${test_ok}, $db"
			else
				test_ok=$db
			fi
		else
			if [ "$test_errors" ]; then
				test_errors="${test_errors}, $db"
			else
				test_errors=$db
			fi
		fi
	fi
done

if [ "$test_errors" ]; then
	output="$output ERROR: $test_errors"
	set_exit_status $STATE_CRITICAL
fi

if [ "$test_ok" ]; then
	output="$output OK: $test_ok"
fi

if [ ! "$output" ]; then
	echo "UNKNOWN: No output"
	exit $STATE_UNKNOWN
fi

echo "$output"
exit $exitstatus