How to reload a task/template?

kapacitor

#1

I am having trouble reloading a task that’s based on a template and variable file. The relevant files are:

├── etc
│   ├── kapacitor
│   │   └── load
│   │       ├── tasks
│   │       │   ├── project_4_sigma_windspeed.json
│   │       └── templates
│   │           └── sigma_template.tick

The kapacitor service loads it correctly and it runs fine, but if I want to change a variable in the json file, I need to restart the kapacitor service for the changes to be realized. It seems like there should be some sort of reloading process or redefining

sigma_template.tick

// measurement
var measurement = ''

// tags to group by
var groupby = [*]

// field
var field = ''

// How many stddevs away from the mean will trigger a critical alert
var crit_sigma_level = 3.0

// How many stddevs away from the mean will trigger a warning alert
var warn_sigma_level = 1.5

// Window for computing sigma
var sigma_window = 10s

// critical alert message
var crit_message = 'Critical sigma level'

// warn alert message
var warn_message = 'Warning sigma level'

// critical alert message
var ok_message = 'OK'



// PROCESSING

var data = stream
    |from()
        .measurement(measurement)
        .groupBy(groupby)
    |window()
        .period(sigma_window)
        .align()


var mean_field = data
    |mean(field)
        .as('mean_field')


var last_field = data
    |last(field)
        .as('last_field')


var stddev_field = data
    |stddev(field)
        .as('stddev_field')


var sigma_field = mean_field
    |join(last_field, stddev_field)
        .as('A', 'B', 'C')
    |eval(lambda: abs("B.last_field"-"A.mean_field")/"C.stddev_field")
        .as('sigma_field')


sigma_field
    |influxDBOut()
        .create()
        .database('debugging')
        .retentionPolicy('autogen')
        .measurement('debug2')
        .precision('s')

project_4_sigma_windspeed.json

{
  "dbrps": [{"db": "project_4", "rp": "thirty_days"}],
  "template-id": "sigma_template",
  "vars": {
            "measurement":      {"type": "string",   "value": "project_4"},
            "field":            {"type": "string",   "value": "windspeed"},
            "crit_sigma_level": {"type": "float",    "value": 8.0},
            "warn_sigma_level": {"type": "float",    "value": 3.3},
            "sigma_window":     {"type": "duration", "value": "20s"}
          }
}

define template

./kapacitor define-template sigma_template -tick ../../etc/kapacitor/load/templates/sigma_template.tick

define task

./kapacitor define project_4_sigma_windspeed -template sigma_template -vars ../../etc/kapacitor/load/tasks/project_4_sigma_windspeed.json

show task (the relevant bits)

Vars:
Name                          Type      Value
crit_sigma_level              float     8
field                         string    windspeed
measurement                   string    project_4
sigma_window                  duration  20s
warn_sigma_level              float     3.3

All works fine at this point. But if I want to change a value in the variable json, like change “warn_sigma_level” to 5.0, the only thing that works to register this change is to restart the kapacitord process.

reload tasks

I tried reloading the tasks:
./kapacitor reload project_4_sigma_windspeed
./kapacitor show project_4_sigma_windspeed

>        Vars:
>         Name                          Type      Value
>         crit_sigma_level              float     8
>         field                         string    windspeed
>         measurement                   string    project_4
>         sigma_window                  duration  20s
>         warn_sigma_level              float     3.3

redefine template

I tried re-defining the template:
./kapacitor define-template sigma_template -tick ../../etc/kapacitor/load/templates/sigma_template.tick
./kapacitor show project_4_sigma_windspeed

Vars:
Name Type Value
crit_sigma_level float 8
field string windspeed
measurement string project_4
sigma_window duration 20s
warn_sigma_level float 3.3

restart kapacitord

The only thing that works is to restart the kapacitor service.
Then, the changes are realized:
./kapacitor show project_4_sigma_windspeed

Vars:
Name                          Type      Value
crit_sigma_level              float     8
field                         string    windspeed
measurement                   string    project_4
sigma_window                  duration  20s
warn_sigma_level              float     5

Having to restart the kapacitor service every time I change a variable seems kinda kludgy. Is there another way to reload a task that’s defined by a template and json variable file?

Thanks

edit: sorry about formatting. I don’t know how to do it.


#2

We are facing same issue. Can anyone please answer if reloading of task is possible instead of restarting kapacitor service?


#3

You could try disable task , enable task after a change …