Monitors

Inside config/ folder there is a file called monitors.yaml. We will be adding our monitors here. Please note that your yaml must be valid. It is an array.

Understanding monitors

Each monitor runs at 1 minute interval by default. Monitor runs in below priority order.

• defaultStatus Data. Used to set the default status of the monitor
• PING/API/DNS call Data overrides above data(if present)
• Pushed Status Data overrides status Data using Kener Update Statue API
• Manual Incident Data overrides Pushed Status Data

General Attributes

A list of attributes that can be used in all types of monitors.

Key	Required?	Explanation
name	Required + Unique	This will be shown in the UI to your users. Keep it short and unique
description	Optional	This is a breif description for the monitor
tag	Required + Unique	This is used to tag incidents created in Github using comments
image	Optional	To show a logo before the name
cron	Optional	Use a valid cron expression to specify the interval to run the monitors. Defaults to * * * * * i.e every minute
defaultStatus	Optional	This will be the default status if no other way is specified to check the monitor. can be UP/DOWN/DEGRADED
hidden	Optional	If set to true will not show the monitor in the UI
category	Optional	Use this to group your monitors. Make sure you have defined category in site.yaml and use the name attribute. More about it here.
dayDegradedMinimumCount	Optional	Default is 1. It means, minimum this number of count for the day to be classified as DEGRADED(Yellow Bar) in 90 day view. Has to be number greater than 0
dayDownMinimumCount	Optional	Default is 1. It means, minimum this number of count for the day to be classified as DOWN(Red Bar) in 90 day view. Has to be number greater than 0
includeDegradedInDowntime	Optional	By deafault uptime percentage is calculated as (UP+DEGRADED/UP+DEGRADED+DOWN). Setting it as true will change the calculation to (UP/UP+DEGRADED+DOWN)

Example

- name: "Google"
  description: "Google Search Engine"
  tag: "google"
  image: "https://www.google.com/images/branding/googlelogo/1x/googlelogo_color_272x92dp.png"
  defaultStatus: "UP"
  hidden: false
  dayDegradedMinimumCount: 2
  dayDownMinimumCount: 3
  includeDegradedInDowntime: false

dayDegradedMinimumCount and dayDownMinimumCount only works when summaryStyle is set as DAY in site.yaml. More about it here

API Monitor Attributes

A list of attributes that can be used in API monitors.

Key	Required?	Explanation
api.url	Required	HTTP URL
api.method	Optional	HTTP Method. Default is GET
api.headers	Optional	HTTP headers
api.body	Optional	HTTP Body as string
api.timeout	Optional	timeout for the api in milliseconds. Default is 10000(10 secs)
api.eval	Optional	Evaluator written in JS, to parse HTTP response and calculate uptime and latency
api.hideURLForGet	Optional	if the monitor is a GET URL and no headers are specified and the response body content-type is a text/html then kener shows a GET hyperlink in monitor description. To hide that set this as false. Default is true

Eval

This is a anonymous JS function, by default it looks like this.

NOTE: The eval function should always return a json object. The json object can have only status(UP/DOWN/DEGRADED) and lantecy(number) {status:"DEGRADED", latency: 200}.

(function (statusCode, responseTime, responseDataBase64) {
    let statusCodeShort = Math.floor(statusCode/100);
    let status = 'DOWN'
    if(statusCodeShort >=2 && statusCodeShort <= 3) {
        status = 'UP',
    }
    return {
        status: 'DOWN',
        latency: responseTime,
    }
})

• statusCode REQUIRED is a number. It is the HTTP status code
• responseTime REQUIREDis a number. It is the latency in milliseconds
• responseDataBase64 REQUIRED is a string. It is the base64 encoded response data. To use it you will have to decode it

let decodedResp = atob(responseDataBase64);
//let jsonResp = JSON.parse(decodedResp)

Example

- name: "Google"
  description: "Google Search Engine"
  tag: "google"
  image: "https://www.google.com/images/branding/googlelogo/1x/googlelogo_color_272x92dp.png"
  defaultStatus: "UP"
  hidden: false
  api:
    url: "https://www.google.com"
    method: "GET"
    headers:
      "Content-Type": "application/json"
    body: ""
    timeout: 10000
    eval: |
      (function (statusCode, responseTime, responseDataBase64) {
        let statusCodeShort = Math.floor(statusCode/100);
        let status = 'DOWN'
        if(statusCodeShort >=2 && statusCodeShort <= 3) {
            status = 'UP',
        }
        return {
            status: 'DOWN',
            latency: responseTime,
        }
      })

To view more examples of API monitors, please visit here

PING Monitor Attributes

A list of attributes that can be used in PING monitors.

Key	Required?	Explanation
ping.hostsV4	Required	Array of hosts / IP to monitor ping response. Either domain name or IP4
ping.hostsV6	Required	Array of hosts / IP to monitor ping response. Either domain name or IP6

Either one of hostsV4 or hostsV6 is required

Example

- name: "Ping All"
  description: "Ping All is where I ping all the hosts"
  tag: "pingall"
  defaultStatus: "UP"
  ping:
    hostsV4:
        - "www.rajnandan.com"
      	- "103.125.217.243"

You can find more examples of PING monitors here

DNS Monitor Attributes

A list of attributes that can be used in DNS monitors.

Key	Required?	Explanation
dns.hosts	Required	Array of hosts to monitor DNS response. Either domain name or IP4 or IP6
dns.lookupRecord	Required	DNS record type.
dns.nameServer	Required	DNS server to use.
dns.matchType	Required	Match type for DNS response. Can be ANY or ALL. Default is ALL
dns.values	Required	Expected values for the DNS response. Array of string

Example

- name: "DNS All"
  description: "DNS All is where I check all the DNS"
  tag: "dnsall"
  defaultStatus: "UP"
  dns:
      host: "www.rajnandan.com"
      lookupRecord: "CNAME"
      nameServer: "8.8.8.8"
      matchType: "ANY"
      values:
          - "rajnandan1.github.io"