monitor.check() function

The monitor.check() function checks input data and assigns a level (ok, info, warn, or crit) to each row based on predicate functions.

*Function type: Transformation*

import "influxdata/influxdb/monitor"
monitor.check(
  crit: (r) => r._value > 90.0,
  warn: (r) => r._value > 80.0,
  info: (r) => r._value > 60.0,
  ok:   (r) => r._value <= 20.0,
  messageFn: (r) => "The current level is ${r._level}",
  data: {}
)

monitor.check() stores statuses in the _level column and writes results to the statuses measurement in the _monitoring bucket.

Parameters

crit

Predicate function that determines crit status. Default is (r) => false.

*Data type: Function*

warn

Predicate function that determines warn status. Default is (r) => false.

*Data type: Function*

info

Predicate function that determines info status. Default is (r) => false.

*Data type: Function*

ok

Predicate function that determines ok status. Default is (r) => true.

*Data type: Function*

messageFn

A function that constructs a message to append to each row. The message is stored in the _message column.

*Data type: Function*

data

Meta data used to identify this check.

InfluxDB populates check data.

*Data type: Record*

Examples

Monitor disk usage

import "influxdata/influxdb/monitor"
from(bucket: "telegraf")
  |> range(start: -1h)
  |> filter(fn: (r) =>
      r._measurement == "disk" and
      r._field = "used_percent"
  )
  |> group(columns: ["_measurement"])
  |> monitor.check(
    crit: (r) => r._value > 90.0,
    warn: (r) => r._value > 80.0,
    info: (r) => r._value > 70.0,
    ok:   (r) => r._value <= 60.0,
    messageFn: (r) =>
      if r._level == "crit" then "Critical alert!! Disk usage is at ${r._value}%!"
      else if r._level == "warn" then "Warning! Disk usage is at ${r._value}%."
      else if r._level == "info" then "Disk usage is at ${r._value}%."
      else "Things are looking good.",
    data: {
      _check_name: "Disk Utilization (Used Percentage)",
      _check_id: "disk_used_percent",
      _type: "threshold",
      tags: {}
    }
  )