Nagios/Icinga2 plugin to check JSON attributes via http(s).
This Plugin is a fork of the existing JSON Plugin from https://github.com/c-kr/check_json with the enhancements of using the Monitoring::Plugin Perl Module, allowing to use thresholds and performance data collection from various json attributes, and of https://github.com/jiririedl/check_json supporting X-Auth and Bearer Token authorization methods. Performance data is also enhanced to extract performance data compliant to Nagios and Graphite standards. One attribute is selected for thresholds check, multiple others can be added for extracting performance data. This plugin is aimed at simplifying Nagios, Icinga & Icinga2 polling of JSON status APIs.
This particular fork allows to check for dates in the JSON. The date is compared against the current time and the difference in seconds is used as attribute. Also perfvars and outputvars is fixed for more easy access, just as it was implemented for attributes.
This fork also allows you to specify multiple valid values (int or String) for the critical / warning / normal parameters. This changes the interpretation of --critical and --warning to arrays of valid values (values delimited by ';'). Single values can still be given as before and are interpreted as before. A new parameter will be added (--normal) which will work the same as --warning or --critical but won't have any effect on thresholds.
Please note: You should not use --expect and --normal/--warning/--critical together! Expect is a binary comparison (result = expected value --> OK / result != expected value --> CRITICAL). --normal/--warning/--critical can be used with arrays of (or single) valid values for each result (normal/warning/critical) and/or with integer thresholds (see more and how under 'Input->Output Examples'). When --expect is given the parameters --normal/--warning/--critical and their values will be ignored.
check_json
-u|--url <URL>
-a|--attribute <attribute>
[ -c|--critical <integer threshold/array of valid values> ]
[ -w|--warning <integer threshold/array of valid values> ]
[ -n|--normal <array of valid values> ]
[ -e|--expect <value>]
[ -p|--perfvars <fields> ]
[ -o|--outputvars <fields> ]
[ -t|--timeout <timeout> ]
[ -d|--divisor <divisor> ]
[ -m|--metadata ]
[ -T|--contenttype <content-type> ]
[ --ignoressl ]
[ -x|--xauth <X-Auth-Token> ]
[ -b|--bearer <Bearer-Token> ]
[ -A|--hattrib <value> ]
[ -C|--hcon <value> ]
[--isdate]
[ -h|--help ]
check_json
-u|--url <URL>
-a|--attribute <attribute>
-e|--expect <value>
[ -p|--perfvars <fields> ]
[ -o|--outputvars <fields> ]
[ -t|--timeout <timeout> ]
[ -d|--divisor <divisor> ]
[ -m|--metadata ]
[ -T|--contenttype <content-type> ]
[ --ignoressl ]
[ -x|--xauth <X-Auth-Token> ]
[ -b|--bearer <Bearer-Token> ]
[ -A|--hattrib <value> ]
[ -C|--hcon <value> ]
[--isdate]
check_json
-u|--url <URL>
-a|--attribute <attribute>
-c|--critical <integer threshold/array of valid values>
-w|--warning <integer threshold/array of valid values>
( -n|--normal <array of valid values> )
[ -p|--perfvars <fields> ]
[ -o|--outputvars <fields> ]
[ -t|--timeout <timeout> ]
[ -d|--divisor <divisor> ]
[ -m|--metadata ]
[ -T|--contenttype <content-type> ]
[ --ignoressl ]
[ -x|--xauth <X-Auth-Token> ]
[ -b|--bearer <Bearer-Token> ]
[ -A|--hattrib <value> ]
[ -C|--hcon <value> ]
[--isdate]
COMMAND BASE: ./check_json.pl -u URL <COMMAND SUFFIX>
TYPE | COMMAND SUFFIX | URL_RESPONSE | RES |
---|---|---|---|
Single | -a '{status}' --expect "ok" | {"status":"ok"} | OK |
Single | -a '{errors}' --expect "0" | {"errors":"0"} | OK |
Multiple | -a '{status},{patched}' --expect "ok" | {{"status":"ok"},{"patched":"ok"} | OK |
Single Nested | -a '{status}->{server}' --expect "ok" | {"status":{"server":"ok"}} | OK |
Multiple Nested | -a '{status}->{server},{status}->{gateway}' --expect "ok" | {"status":{"server":"ok"},{"gateway":"ok"}} | OK |
Single | -a '{status}' --expect "ok" | {"status":"anything else"} | CRIT |
Multiple | -a '{status},{patched}' --expect "ok" | {{"status":"anything else"},{"patched":"ok"} | CRIT |
Multiple | -a '{status},{errors}' --expect "ok" | {{"status":"ok"},{"errors":"0"} | CRIT |
Multiple | -a '{status},{patched}' --expect "ok" | {{"status":"ok"},{"patched":"anything else"} | CRIT |
Single Nested | -a '{status}->{server}' --expect "ok" | {"status":{"server":"anything else"}} | CRIT |
Multiple Nested | -a '{status}->{server},{status}->{gateway}' --expect "ok" | {"status":{"server":"anything else"},{"gateway":"ok"}} | CRIT |
Multiple Nested | -a '{status}->{server},{status}->{gateway}' --expect "ok" | {"status":{"server":"ok"},{"gateway":"anything else"}} | CRIT |
COMMAND BASE: ./check_json.pl -u URL <COMMAND SUFFIX>
TYPE | COMMAND SUFFIX | URL_RESPONSE | RES |
---|---|---|---|
Single | -a '{connections}' --warning 10 --critical 20 | {"connections":"9"} | OK |
Single | -a '{connections}' --warning 10 --critical 20 | {"connections":"10"} | WARN |
Single | -a '{connections}' --warning 10 --critical 20 | {"connections":"19"} | WARN |
Single | -a '{connections}' --warning 10 --critical 20 | {"connections":"20"} | CRIT |
Multiple | -a '{connections},{sessions}' -w 10 -c 20 | {"connections":"9"},{"sessions":"8"} | OK |
Multiple | -a '{connections},{sessions}' -w 10 -c 20 | {"connections":"9"},{"sessions":"11"} | WARN |
Multiple | -a '{connections},{sessions}' -w 10 -c 20 | {"connections":"22"},{"sessions":"12"} | CRIT |
Single Nested | -a '{connections}->{last_5_min}' -w 10 -c 20 | {"connections":{"last_5_min":"5"}} | OK |
Single Nested | -a '{connections}->{last_5_min}' -w 10 -c 20 | {"connections":{"last_5_min":"30"}} | CRIT |
Multiple Nested | -a '{load}->{last_5_min},{load}->{last_1_min}' -w 3 -c 4 | {"load":{"last_5_min":"0.5"},{"last_1_min":"1.0"}} | OK |
Multiple Nested | -a '{load}->{last_5_min},{load}->{last_1_min}' -w 3 -c 4 | {"load":{"last_5_min":"0.5"},{"last_1_min":"5.0"}} | CRIT |
COMMAND BASE: ./check_json.pl -u URL <COMMAND SUFFIX>
TYPE | COMMAND SUFFIX | URL_RESPONSE | RES |
---|---|---|---|
Single | -a '{status}' -n "ok" -w "init;warn" -c "err" | {"status":"ok"} | OK |
Single | -a '{status}' -n "ok" -w "init;warn" -c "err" | {"status":"init"} | WARN |
Single | -a '{status}' -n "ok" -w "init;warn" -c "err" | {"status":"warn"} | WARN |
Single | -a '{status}' -n "ok" -w "init;warn" -c "err" | {"status":"err"} | CRIT |
Multiple | -a '{status},{patches}' -n "ok" -w "warn;available" -c "err;sec" | {{"status":"ok"},{"patches":"ok"}} | OK |
Multiple | -a '{status},{patches}' -n "ok" -w "warn;available" -c "err;sec" | {{"status":"ok"},{"patches":"available"}} | WARN |
Multiple | -a '{status},{patches}' -n "ok" -w "warn;available" -c "err;sec" | {{"status":"warn"},{"patches":"ok"}} | WARN |
Multiple | -a '{status},{patches}' -n "ok" -w "warn;available" -c "err;sec" | {{"status":"ok"},{"patches":"sec"}} | CRIT |
Multiple | -a '{status},{patches}' -n "ok" -w "warn;available" -c "err;sec" | {{"status":"err"},{"patches":"available"}} | CRIT |
Single Nested | -a '{status}->{patches}' -n "ok" -w "available" -c "sec" | {"status":{"patches":"ok"}} | OK |
Single Nested | -a '{status}->{patches}' -n "ok" -w "available" -c "sec" | {"status":{"patches":"available"}} | WARN |
Single Nested | -a '{status}->{patches}' -n "ok" -w "available" -c "sec" | {"status":{"patches":"sec"}} | CRIT |
Multiple Nested | -a '{srv}->{www},{srv}->{mail}' -n "ok" -w "warn" -c "err" | {"srv":{"www":"ok"},{"mail":"ok"}} | OK |
Multiple Nested | -a '{srv}->{www},{srv}->{mail}' -n "ok" -w "warn" -c "err" | {"srv":{"www":"ok"},{"mail":"err"}} | CRIT |
Multiple Nested | -a '{srv}->{www},{srv}->{mail}' -n "ok" -w "warn" -c "err" | {"srv":{"www":"warn"},{"mail":"ok"}} | WARN |
The threshold of a value is only calculated if it is not equal to any valid value of the other kinds (normal and/or warning and/or critical). The threshold definition of a result (normal/warning/critical) must be the first in an array of valid values.
COMMAND BASE: ./check_json.pl -u URL <COMMAND SUFFIX>
TYPE | COMMAND SUFFIX | URL_RESPONSE | RES |
---|---|---|---|
Single | -a '{updates}' -n "ok" -w "5" -c "10" | {"updates":"ok"} | OK |
Single | -a '{updates}' -n "ok" -w "5" -c "10" | {"updates":"0"} | OK |
Single | -a '{updates}' -n "ok" -w "5" -c "10" | {"updates":"3"} | OK |
Single | -a '{updates}' -n "ok" -w "5" -c "10" | {"updates":"6"} | WARN |
Single | -a '{updates}' -n "ok" -w "5" -c "10" | {"updates":"6"} | CRIT |
Single | -a '{updates}' -n "ok" -w "5" -c "10;err" | {"updates":"err"} | CRIT |
The other types (multiple, single nested, multiple nested) are also possible but redacted to short the readme, see above
Using divisor 3600 allows to set warning und critical in the perspective of hours.
./check_json.pl -u https://some.thing/event -a "{items}[0]->{modifiedAt}" --warning 24 --critical 48 -divisor 3600 --isdate -o "{items}[0]->{modifiedAt}"
Result:
Check JSON status API OK - modifiedAt: 2021-08-31T13:47:07.341Z
./check_json.pl -u https://some.thing/event -a "{items}[0]->{modifiedAt},{'pagination:page'}->{totalCount}" -w 24,10: -c 48,1: -d 3600 --isdate 1,0 -o "{items}[0]->{modifiedAt},{'pagination:page'}->{totalCount}"
Results:
Check JSON status API OK - modifiedAt: 2021-08-31T13:47:07.341Z, totalCount: 351
Example:
./check_json.pl --url http://192.168.5.10:9332/local_stats --attribute '{shares}->{dead_shares}' --warning :5 --critical :10 --perfvars '{shares}->{dead_shares},{shares}->{live_shares},{clients}->{clients_connected}'
Result:
Check JSON status API OK - dead_shares: 2, live_shares: 12, clients_connected: 234 | dead_shares=2;5;10 live_shares=12 clients_connected=234
Home Assistant Check API Status
./check_json.pl --url http://hass.lan:8123/api/ --attribute '{message}' --expect 'API running.' --bearer LONG_LIVED_ACCESS_TOKEN
Home Assistant Check Entity Status
./check_json.pl --url http://hass.lan:8123/api/states/sensor.living_room_temperature --attribute '{state}' --warning 75 --critical 85 --bearer LONG_LIVED_ACCESS_TOKEN
Perl JSON package
- Debian / Ubuntu : libjson-perl libmonitoring-plugin-perl libwww-perl libdatetime-format-iso8601-perl
Example CheckCommand Definition:
/*
* JSON Check Command
*/
object CheckCommand "check-json" {
import "plugin-check-command"
command = [ PluginDir + "/check_json.pl" ]
arguments = {
"-u" = {
required = true
value = "$json_url$"
}
"-a" = {
required = true
value = "$json_attributes$"
}
"-d" = "$json_divisor$"
"-w" = "$json_warning$"
"-c" = "$json_critical$"
"-n" = "$json_normal$"
"-e" = "$json_expect$"
"-p" = "$json_perfvars$"
"-o" = "$json_outvars$"
"-m" = "$json_metadata$"
"--isdate" = {
set_if = "$json_isdate$"
description = "Handles the attribute as a datetime and computes the time difference to the current datetime."
}
"--ignoressl" = {
set_if = "$json_ignoressl$"
description = "Ignore bad SSL certificates"
}
"-x" = {
value = "$json_xauth_token$"
description = "Add an X-Auth-Token header with the specified token"
}
"-b" = {
value = "$json_bearer_token$"
description = "Add an Authorization: Bearer header with the specified token"
}
}
}
Example Service Check Definition:
/*
* Home Assistant API Check
*/
object Service "hass-api" {
host_name = "hass.lan"
check_command = "check-json"
vars.json_url = "http://$address$:8123/api/"
vars.json_attributes = "{message}"
vars.json_expect = "API running."
vars.json_bearer_token = "LONG_LIVED_ACCESS_TOKEN"
}