gitorious/nagios-http-json
1
0
Fork 0
mirror of https://github.com/drewkerrigan/nagios-http-json.git synced 2024-11-22 02:13:47 +01:00
Code Issues Releases Wiki Activity
fb4e58b635
nagios-http-json/README.md

281 lines
11 KiB
Markdown
Raw Blame History

# Nagios Json Plugin
This is a generic plugin for Nagios which checks json values from a given HTTP endpoint against argument specified rules and determines the status and performance data for that service.
### Installation
#### Requirements
* Nagios
* Python
### Nagios Configuration
Assuming a standard installation of Nagios, the plugin can be executed from the machine that Nagios is running on.
```bash
cp check_http_json.py /usr/local/nagios/libexec/plugins/check_http_json.py
chmod +x /usr/local/nagios/libexec/plugins/check_http_json.py
```
Add the following service definition to your server config (`localhost.cfg`):
```
define service {
use local-service
host_name localhost
service_description <command_description>
check_command <command_name>
}
```
Add the following command definition to your commands config (`commands.config`):
```
define command{
command_name <command_name>
command_line /usr/bin/python /usr/local/nagios/libexec/plugins/check_http_json.py -H <host>:<port> -p <path> [-e|-q|-w|-c <rules>] [-m <metrics>]
}
```
More info about options in Usage.
### CLI Usage
Executing `./check_http_json.py -h` will yield the following details:
```
usage: check_http_json.py [-h] [-d] [-s] -H HOST [-P PORT] [-p PATH]
[-t TIMEOUT] [-B AUTH] [-D DATA] [-f SEPARATOR]
[-w [KEY_THRESHOLD_WARNING [KEY_THRESHOLD_WARNING ...]]]
[-c [KEY_THRESHOLD_CRITICAL [KEY_THRESHOLD_CRITICAL ...]]]
[-e [KEY_LIST [KEY_LIST ...]]]
[-E [KEY_LIST_CRITICAL [KEY_LIST_CRITICAL ...]]]
[-q [KEY_VALUE_LIST [KEY_VALUE_LIST ...]]]
[-Q [KEY_VALUE_LIST_CRITICAL [KEY_VALUE_LIST_CRITICAL ...]]]
[-m [METRIC_LIST [METRIC_LIST ...]]]
Nagios plugin which checks json values from a given endpoint against argument
specified rules and determines the status and performance data for that
service
optional arguments:
-h, --help show this help message and exit
-d, --debug Debug mode.
-s, --ssl HTTPS mode.
-H HOST, --host HOST Host.
-P PORT, --port PORT TCP port
-p PATH, --path PATH Path.
-t TIMEOUT, --timeout TIMEOUT
Connection timeout (seconds)
-B AUTH, --basic-auth AUTH
Basic auth string "username:password"
-D DATA, --data DATA The http payload to send as a POST
-f SEPARATOR, --field_separator SEPARATOR
Json Field separator, defaults to "." ; Select element
in an array with "(" ")"
-w [KEY_THRESHOLD_WARNING [KEY_THRESHOLD_WARNING ...]], --warning [KEY_THRESHOLD_WARNING [KEY_THRESHOLD_WARNING ...]]
Warning threshold for these values
(key1[>alias],WarnRange key2[>alias],WarnRange).
WarnRange is in the format [@]start:end, more
information at nagios-plugins.org/doc/guidelines.html.
-c [KEY_THRESHOLD_CRITICAL [KEY_THRESHOLD_CRITICAL ...]], --critical [KEY_THRESHOLD_CRITICAL [KEY_THRESHOLD_CRITICAL ...]]
Critical threshold for these values
(key1[>alias],CriticalRange
key2[>alias],CriticalRange. CriticalRange is in the
format [@]start:end, more information at nagios-
plugins.org/doc/guidelines.html.
-e [KEY_LIST [KEY_LIST ...]], --key_exists [KEY_LIST [KEY_LIST ...]]
Checks existence of these keys to determine status.
Return warning if key is not present.
-E [KEY_LIST_CRITICAL [KEY_LIST_CRITICAL ...]], --key_exists_critical [KEY_LIST_CRITICAL [KEY_LIST_CRITICAL ...]]
Same as -e but return critical if key is not present.
-q [KEY_VALUE_LIST [KEY_VALUE_LIST ...]], --key_equals [KEY_VALUE_LIST [KEY_VALUE_LIST ...]]
Checks equality of these keys and values
(key[>alias],value key2,value2) to determine status.
Multiple key values can be delimited with colon
(key,value1:value2). Return warning if equality check
fails
-Q [KEY_VALUE_LIST_CRITICAL [KEY_VALUE_LIST_CRITICAL ...]], --key_equals_critical [KEY_VALUE_LIST_CRITICAL [KEY_VALUE_LIST_CRITICAL ...]]
Same as -q but return critical if equality check
fails.
-m [METRIC_LIST [METRIC_LIST ...]], --key_metric [METRIC_LIST [METRIC_LIST ...]]
Gathers the values of these keys (key[>alias],UnitOfMe
asure,WarnRange,CriticalRange,Min,Max) for Nagios
performance data. More information about Range format
and units of measure for nagios can be found at
nagios-plugins.org/doc/guidelines.html Additional
formats for this parameter are: (key[>alias]),
(key[>alias],UnitOfMeasure),
(key[>alias],UnitOfMeasure,WarnRange,CriticalRange).
```
Access a specific JSON field by following this syntax: `alpha.beta.gamma(3).theta.omega(0)`
Dots are field separators (changeable), parentheses are for entering arrays.
If the root of the JSON data is itself an array like the following:
```
[
{ "gauges": { "jvm.buffers.direct.capacity": {"value": 215415}}}
]
```
The beginning of the key should start with ($index) as in this example:
```
./check_http_json.py -H localhost:8081 -p metrics --key_exists "(0)_gauges_jvm.buffers.direct.capacity_value" -f _
```
More info about Nagios Range format and Units of Measure can be found at [https://nagios-plugins.org/doc/guidelines.html](https://nagios-plugins.org/doc/guidelines.html).
### Docker Info Example Plugin
#### Description
Let's say we want to use `check_http_json.py` to read from Docker's `/info` HTTP API endpoint with the following parameters:
##### Connection information
* Host = 127.0.0.1:4243
* Path = /info
##### Rules for "aliveness"
* Verify that the key `Containers` exists in the outputted JSON
* Verify that the key `IPv4Forwarding` has a value of `1`
* Verify that the key `Debug` has a value less than or equal to `2`
* Verify that the key `Images` has a value greater than or equal to `1`
* If any of these criteria are not met, report a WARNING to Nagios
##### Gather Metrics
* Report value of the key `Containers` with a MinValue of 0 and a MaxValue of 1000 as performance data
* Report value of the key `Images` as performance data
* Report value of the key `NEventsListener` as performance data
* Report value of the key `NFd` as performance data
* Report value of the key `NGoroutines` as performance data
* Report value of the key `SwapLimit` as performance data
#### Service Definition
`localhost.cfg`
```
define service {
use local-service
host_name localhost
service_description Docker info status checker
check_command check_docker
}
```
#### Command Definition with Arguments
`commands.cfg`
```
define command{
command_name check_docker
command_line /usr/bin/python /usr/local/nagios/libexec/plugins/check_http_json.py -H 127.0.0.1:4243 -p info -e Containers -q IPv4Forwarding,1 -w Debug,2:2 -c Images,1:1 -m Containers,0:250,0:500,0,1000 Images NEventsListener NFd NGoroutines SwapLimit
}
```
#### Sample Output
```
OK: Status OK.|'Containers'=1;0;1000 'Images'=11;0;0 'NEventsListener'=3;0;0 'NFd'=10;0;0 'NGoroutines'=14;0;0 'SwapLimit'=1;0;0
```
### Docker Container Monitor Example Plugin
`check_http_json.py` is generic enough to read and evaluate rules on any HTTP endpoint that returns JSON. In this example we'll get the status of a specific container using it's ID which camn be found by using the list containers endpoint (`curl http://127.0.0.1:4243/containers/json?all=1`).
##### Connection information
* Host = 127.0.0.1:4243
* Path = /containers/2356e8ccb3de8308ccb16cf8f5d157bc85ded5c3d8327b0dfb11818222b6f615/json
##### Rules for "aliveness"
* Verify that the key `ID` exists and is equal to the value `2356e8ccb3de8308ccb16cf8f5d157bc85ded5c3d8327b0dfb11818222b6f615`
* Verify that the key `State.Running` has a value of `True`
#### Service Definition
`localhost.cfg`
```
define service {
use local-service
host_name localhost
service_description Docker container liveness check
check_command check_my_container
}
```
#### Command Definition with Arguments
`commands.cfg`
```
define command{
command_name check_my_container
command_line /usr/bin/python /usr/local/nagios/libexec/plugins/check_http_json.py -H 127.0.0.1:4243 -p /containers/2356e8ccb3de8308ccb16cf8f5d157bc85ded5c3d8327b0dfb11818222b6f615/json -q ID,2356e8ccb3de8308ccb16cf8f5d157bc85ded5c3d8327b0dfb11818222b6f615 State.Running,True
}
```
#### Sample Output
```
WARNING: Status check failed, reason: Value True for key State.Running did not match.
```
The plugin threw a warning because the Container ID I used on my system has the following State object:
```
u'State': {...
u'Running': False,
...
```
If I change the command to have the parameter -q parameter `State.Running,False`, the output becomes:
```
OK: Status OK.
```
### Dropwizard / Fieldnames Containing '.' Example
Simply choose a separator to deal with data such as this:
```
{ "gauges": { "jvm.buffers.direct.capacity": {"value": 215415}}}
```
In this example I've chosen `_` to separate `guages` from `jvm` and `capacity` from `value`. The CLI invocation then becomes:
```
./check_http_json.py -H localhost:8081 -p metrics --key_exists gauges_jvm.buffers.direct.capacity_value -f _
```
## License
Copyright 2014-2015 Drew Kerrigan.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
Reference in New Issue View Git Blame Copy Permalink