How to use status panel with Flux Query?

Grafana
, ,
1

Hello, I am using influxDB as data source in Grafana and using flux query for data. Data is a PLC heart-beat data (boolean) and I wrote a simple logic to convert this timeseries boolean data into a simple status message “Alive” or “Dead”. I have to perform this for 10 PLC’s.

I want to use the ‘Status Panel’ but I cannot make it to work. I do not find sufficient documentation. Here is the query:

from(bucket: “Safety_Alarms”)
|> range(start: -20s)
|> filter(fn: (r) => r._measurement == “safety” and r.name == “Aging_1” and r._field == “heart_beat”)
|> keep(columns: [“_time”, “_value”])
|> sort(columns: [“_time”], desc: true)
|> limit(n: 2)
|> reduce(
identity: {first: true, last: true},
fn: (r, accumulator) => ({
first: if accumulator.first == true then r._value else accumulator.first,
last: r._value
})
)
|> map(fn: (r) => ({
_value: if r.first != r.last then “Alive” else “Dead”
}))

|> rename(columns: {_value: “result”})

I have multiple PLC’s and I want to monitor 1 metric for each of them in this status panel. The above code is for 1 PLC. I would appreciate some help with this task. Thank you.

2

Assuming that information on all PLCs is stored in one bucket, each PLC has unique value of name tag and that expected result is the following:

Stat panel
Stat panel1920×971 96.6 KB

One possible solution could look like this:

import "join"

data = <YOUR_DATA_QUERY_FOR_ALL_PLCS>

last = data
|>group(columns:["name"])
|>last()
|>group()

first = data
|>group(columns:["name"])
|>first()
|>group()


join.left(
    left: first,
    right: last,
    on: (l, r) => l.name == r.name,
    as: (l, r) => ({name: l.name, status : if l._value == r._value then "Dead" else "Alive"}),
)