BarrierNode

stream
  |from()
    .measurement('cpu')
  |barrier()
    .idle(11s) // Must be longer than the window period
    .delete(TRUE)
  |window()
    .period(10s)
    .every(5s)
  |top(10, 'value')
  // Post the top 10 results over the last 10s updated every 5s.
  |httpPost('http://example.com/api/top10')

barrier.idle(value time.Duration)

barrier.period(value time.Duration)

barrier.delete()

barrier.quiet()

barrier|alert()

barrier|barrier()

barrier|bottom(num int64, field string, fieldsAndTags ...string)

barrier|changeDetect(field string)

barrier|combine(expressions ...ast.LambdaNode)

barrier|count(field string)

barrier|cumulativeSum(field string)

    var data = stream
        |from()...
    // Trigger critical alert if the throughput drops below 100 points per 10s and checked every 10s.
    data
        |deadman(100.0, 10s)
    //Do normal processing of data
    data...

    var data = stream
        |from()...
    // Trigger critical alert if the throughput drops below 100 points per 10s and checked every 10s.
    data
        |stats(10s)
            .align()
        |derivative('emitted')
            .unit(10s)
            .nonNegative()
        |alert()
            .id('node \'stream0\' in task \'{{ .TaskName }}\'')
            .message('{{ .ID }} is {{ if eq .Level "OK" }}alive{{ else }}dead{{ end }}: {{ index .Fields "emitted" | printf "%0.3f" }} points/10s.')
            .crit(lambda: "emitted" <= 100.0)
    //Do normal processing of data
    data...

    var data = stream
        |from()...
    // Trigger critical alert if the throughput drops below 100 points per 10s and checked every 10s.
    data
        |deadman(100.0, 10s)
            .slack()
            .channel('#dead_tasks')
    //Do normal processing of data
    data...

    var data = stream
        |from()...
    // Trigger critical alert if the throughput drops below 100 points per 10s and checked every 10s.
    // Only trigger the alert if the time of day is between 8am-5pm.
    data
        |deadman(100.0, 10s, lambda: hour("time") >= 8 AND hour("time") <= 17)
    //Do normal processing of data
    data...

barrier|deadman(threshold float64, interval time.Duration, expr ...ast.LambdaNode)

barrier|default()

barrier|delete()

barrier|derivative(field string)

barrier|difference(field string)

barrier|distinct(field string)

barrier|ec2Autoscale()

barrier|elapsed(field string, unit time.Duration)

barrier|eval(expressions ...ast.LambdaNode)

barrier|first(field string)

barrier|flatten()

    |groupBy(*)

barrier|groupBy(tag ...interface{})

barrier|holtWinters(field string, h int64, m int64, interval time.Duration)

barrier|holtWintersWithFit(field string, h int64, m int64, interval time.Duration)

barrier|httpOut(endpoint string)

barrier|httpPost(url ...string)

barrier|influxDBOut()

barrier|join(others ...Node)

barrier|k8sAutoscale()

barrier|kapacitorLoopback()

barrier|last(field string)

barrier|log()

barrier|max(field string)

barrier|mean(field string)

barrier|median(field string)

barrier|min(field string)

barrier|mode(field string)

barrier|movingAverage(field string, window int64)

barrier|percentile(field string, percentile float64)

barrier|sample(rate interface{})

barrier|shift(shift time.Duration)

barrier|sideload()

barrier|spread(field string)

barrier|stateCount(expression ast.LambdaNode)

barrier|stateDuration(expression ast.LambdaNode)

barrier|stats(interval time.Duration)

barrier|stddev(field string)

barrier|sum(field string)

barrier|swarmAutoscale()

barrier|top(num int64, field string, fieldsAndTags ...string)

barrier|trickle()

barrier|union(node ...Node)

barrier|where(expression ast.LambdaNode)

barrier|window()