2020-07-30 16:38:32 +00:00
---
title: StateCountNode (Kapacitor TICKscript node)
description: StateCountNode computes the number of consecutive points in a given state (defined using a lambda expression).
note: Auto generated by tickdoc
menu:
kapacitor_1_4:
name: StateCountNode
identifier: state_count_node
weight: 260
parent: TICKscript nodes
---
### Constructor
| Chaining Method | Description |
|:---------|:---------|
| ** [stateCount ](#descr ) ( `expression` `ast.LambdaNode`)** | Create a node that tracks number of consecutive points in a given state. |
### Property Methods
| Setters | Description |
|:---|:---|
| ** [as ](#as ) ( `value` `string`)** | The new name of the resulting duration field. Default: 'state_count' |
### Chaining Methods
[Alert ](/kapacitor/v1.4/nodes/state_count_node/#alert ), [Barrier ](/kapacitor/v1.4/nodes/state_count_node/#barrier ), [Bottom ](/kapacitor/v1.4/nodes/state_count_node/#bottom ), [Combine ](/kapacitor/v1.4/nodes/state_count_node/#combine ), [Count ](/kapacitor/v1.4/nodes/state_count_node/#count ), [CumulativeSum ](/kapacitor/v1.4/nodes/state_count_node/#cumulativesum ), [Deadman ](/kapacitor/v1.4/nodes/state_count_node/#deadman ), [Default ](/kapacitor/v1.4/nodes/state_count_node/#default ), [Delete ](/kapacitor/v1.4/nodes/state_count_node/#delete ), [Derivative ](/kapacitor/v1.4/nodes/state_count_node/#derivative ), [Difference ](/kapacitor/v1.4/nodes/state_count_node/#difference ), [Distinct ](/kapacitor/v1.4/nodes/state_count_node/#distinct ), [Ec2Autoscale ](/kapacitor/v1.4/nodes/state_count_node/#ec2autoscale ), [Elapsed ](/kapacitor/v1.4/nodes/state_count_node/#elapsed ), [Eval ](/kapacitor/v1.4/nodes/state_count_node/#eval ), [First ](/kapacitor/v1.4/nodes/state_count_node/#first ), [Flatten ](/kapacitor/v1.4/nodes/state_count_node/#flatten ), [GroupBy ](/kapacitor/v1.4/nodes/state_count_node/#groupby ), [HoltWinters ](/kapacitor/v1.4/nodes/state_count_node/#holtwinters ), [HoltWintersWithFit ](/kapacitor/v1.4/nodes/state_count_node/#holtwinterswithfit ), [HttpOut ](/kapacitor/v1.4/nodes/state_count_node/#httpout ), [HttpPost ](/kapacitor/v1.4/nodes/state_count_node/#httppost ), [InfluxDBOut ](/kapacitor/v1.4/nodes/state_count_node/#influxdbout ), [Join ](/kapacitor/v1.4/nodes/state_count_node/#join ), [K8sAutoscale ](/kapacitor/v1.4/nodes/state_count_node/#k8sautoscale ), [KapacitorLoopback ](/kapacitor/v1.4/nodes/state_count_node/#kapacitorloopback ), [Last ](/kapacitor/v1.4/nodes/state_count_node/#last ), [Log ](/kapacitor/v1.4/nodes/state_count_node/#log ), [Max ](/kapacitor/v1.4/nodes/state_count_node/#max ), [Mean ](/kapacitor/v1.4/nodes/state_count_node/#mean ), [Median ](/kapacitor/v1.4/nodes/state_count_node/#median ), [Min ](/kapacitor/v1.4/nodes/state_count_node/#min ), [Mode ](/kapacitor/v1.4/nodes/state_count_node/#mode ), [MovingAverage ](/kapacitor/v1.4/nodes/state_count_node/#movingaverage ), [Percentile ](/kapacitor/v1.4/nodes/state_count_node/#percentile ), [Sample ](/kapacitor/v1.4/nodes/state_count_node/#sample ), [Shift ](/kapacitor/v1.4/nodes/state_count_node/#shift ), [Sideload ](/kapacitor/v1.4/nodes/state_count_node/#sideload ), [Spread ](/kapacitor/v1.4/nodes/state_count_node/#spread ), [StateCount ](/kapacitor/v1.4/nodes/state_count_node/#statecount ), [StateDuration ](/kapacitor/v1.4/nodes/state_count_node/#stateduration ), [Stats ](/kapacitor/v1.4/nodes/state_count_node/#stats ), [Stddev ](/kapacitor/v1.4/nodes/state_count_node/#stddev ), [Sum ](/kapacitor/v1.4/nodes/state_count_node/#sum ), [SwarmAutoscale ](/kapacitor/v1.4/nodes/state_count_node/#swarmautoscale ), [Top ](/kapacitor/v1.4/nodes/state_count_node/#top ), [Union ](/kapacitor/v1.4/nodes/state_count_node/#union ), [Where ](/kapacitor/v1.4/nodes/state_count_node/#where ), [Window ](/kapacitor/v1.4/nodes/state_count_node/#window )
< a id = 'descr' / > < hr / > < br / >
### Description
Compute the number of consecutive points in a given state.
The state is defined via a lambda expression. For each consecutive point for
which the expression evaluates as true, the state count will be incremented
When a point evaluates as false, the state count is reset.
The state count will be added as an additional field to each point. If the
expression evaluates as false, the value will be -1. If the expression
generates an error during evaluation, the point is discarded, and does not
affect the state count.
Example:
```javascript
stream
|from()
.measurement('cpu')
|where(lambda: "cpu" == 'cpu-total')
|groupBy('host')
|stateCount(lambda: "usage_idle" < = 10)
|alert()
// Warn after 1 point
.warn(lambda: "state_count" >= 1)
// Critical after 5 points
.crit(lambda: "state_count" >= 5)
```
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Properties
----------
Property methods modify state on the calling node.
They do not add another node to the pipeline, and always return a reference to the calling node.
Property methods are marked using the `.` operator.
### As
The new name of the resulting duration field.
Default: 'state_count'
```javascript
stateCount.as(value string)
```
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Chaining Methods
----------------
Chaining methods create a new node in the pipeline as a child of the calling node.
They do not modify the calling node.
Chaining methods are marked using the `|` operator.
### Alert
Create an alert node, which can trigger alerts.
```javascript
stateCount|alert()
```
Returns: [AlertNode ](/kapacitor/v1.4/nodes/alert_node/ )
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### Barrier
Create a new Barrier node that emits a BarrierMessage periodically
One BarrierMessage will be emitted every period duration
```javascript
stateCount|barrier()
```
Returns: [BarrierNode ](/kapacitor/v1.4/nodes/barrier_node/ )
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### Bottom
Select the bottom `num` points for `field` and sort by any extra tags or fields.
```javascript
stateCount|bottom(num int64, field string, fieldsAndTags ...string)
```
Returns: [InfluxQLNode ](/kapacitor/v1.4/nodes/influx_q_l_node/ )
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### Combine
Combine this node with itself. The data is combined on timestamp.
```javascript
stateCount|combine(expressions ...ast.LambdaNode)
```
Returns: [CombineNode ](/kapacitor/v1.4/nodes/combine_node/ )
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### Count
Count the number of points.
```javascript
stateCount|count(field string)
```
Returns: [InfluxQLNode ](/kapacitor/v1.4/nodes/influx_q_l_node/ )
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### CumulativeSum
Compute a cumulative sum of each point that is received.
A point is emitted for every point collected.
```javascript
stateCount|cumulativeSum(field string)
```
Returns: [InfluxQLNode ](/kapacitor/v1.4/nodes/influx_q_l_node/ )
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### Deadman
Helper function for creating an alert on low throughput, a.k.a. deadman's switch.
- Threshold -- trigger alert if throughput drops below threshold in points/interval.
- Interval -- how often to check the throughput.
- Expressions -- optional list of expressions to also evaluate. Useful for time of day alerting.
Example:
```javascript
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...
```
The above is equivalent to this
Example:
```javascript
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...
```
The `id` and `message` alert properties can be configured globally via the 'deadman' configuration section.
Since the [AlertNode ](/kapacitor/v1.4/nodes/alert_node/ ) is the last piece it can be further modified as usual.
Example:
```javascript
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...
```
You can specify additional lambda expressions to further constrain when the deadman's switch is triggered.
Example:
```javascript
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...
```
```javascript
stateCount|deadman(threshold float64, interval time.Duration, expr ...ast.LambdaNode)
```
Returns: [AlertNode ](/kapacitor/v1.4/nodes/alert_node/ )
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### Default
Create a node that can set defaults for missing tags or fields.
```javascript
stateCount|default()
```
Returns: [DefaultNode ](/kapacitor/v1.4/nodes/default_node/ )
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### Delete
Create a node that can delete tags or fields.
```javascript
stateCount|delete()
```
Returns: [DeleteNode ](/kapacitor/v1.4/nodes/delete_node/ )
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### Derivative
Create a new node that computes the derivative of adjacent points.
```javascript
stateCount|derivative(field string)
```
Returns: [DerivativeNode ](/kapacitor/v1.4/nodes/derivative_node/ )
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### Difference
Compute the difference between points independent of elapsed time.
```javascript
stateCount|difference(field string)
```
Returns: [InfluxQLNode ](/kapacitor/v1.4/nodes/influx_q_l_node/ )
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### Distinct
Produce batch of only the distinct points.
```javascript
stateCount|distinct(field string)
```
Returns: [InfluxQLNode ](/kapacitor/v1.4/nodes/influx_q_l_node/ )
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### Ec2Autoscale
Create a node that can trigger autoscale events for a ec2 autoscalegroup.
```javascript
stateCount|ec2Autoscale()
```
Returns: [Ec2AutoscaleNode ](/kapacitor/v1.4/nodes/ec2_autoscale_node/ )
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### Elapsed
Compute the elapsed time between points
```javascript
stateCount|elapsed(field string, unit time.Duration)
```
Returns: [InfluxQLNode ](/kapacitor/v1.4/nodes/influx_q_l_node/ )
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### Eval
Create an eval node that will evaluate the given transformation function to each data point.
A list of expressions may be provided and will be evaluated in the order they are given.
The results are available to later expressions.
```javascript
stateCount|eval(expressions ...ast.LambdaNode)
```
Returns: [EvalNode ](/kapacitor/v1.4/nodes/eval_node/ )
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### First
Select the first point.
```javascript
stateCount|first(field string)
```
Returns: [InfluxQLNode ](/kapacitor/v1.4/nodes/influx_q_l_node/ )
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### Flatten
Flatten points with similar times into a single point.
```javascript
stateCount|flatten()
```
Returns: [FlattenNode ](/kapacitor/v1.4/nodes/flatten_node/ )
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### GroupBy
Group the data by a set of tags.
Can pass literal * to group by all dimensions.
Example:
```javascript
|groupBy(*)
```
```javascript
stateCount|groupBy(tag ...interface{})
```
Returns: [GroupByNode ](/kapacitor/v1.4/nodes/group_by_node/ )
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### HoltWinters
2020-08-19 22:43:31 +00:00
Compute the holt-winters (/{{< latest " influxdb " " v1 " > }}/query_language/functions/#holt-winters) forecast of a data set.
2020-07-30 16:38:32 +00:00
```javascript
stateCount|holtWinters(field string, h int64, m int64, interval time.Duration)
```
Returns: [InfluxQLNode ](/kapacitor/v1.4/nodes/influx_q_l_node/ )
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### HoltWintersWithFit
2020-08-19 22:43:31 +00:00
Compute the holt-winters (/{{< latest " influxdb " " v1 " > }}/query_language/functions/#holt-winters) forecast of a data set.
2020-07-30 16:38:32 +00:00
This method also outputs all the points used to fit the data in addition to the forecasted data.
```javascript
stateCount|holtWintersWithFit(field string, h int64, m int64, interval time.Duration)
```
Returns: [InfluxQLNode ](/kapacitor/v1.4/nodes/influx_q_l_node/ )
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### HttpOut
Create an HTTP output node that caches the most recent data it has received.
The cached data is available at the given endpoint.
The endpoint is the relative path from the API endpoint of the running task.
For example, if the task endpoint is at `/kapacitor/v1/tasks/<task_id>` and endpoint is
`top10` , then the data can be requested from `/kapacitor/v1/tasks/<task_id>/top10` .
```javascript
stateCount|httpOut(endpoint string)
```
Returns: [HTTPOutNode ](/kapacitor/v1.4/nodes/http_out_node/ )
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### HttpPost
Creates an HTTP Post node that POSTS received data to the provided HTTP endpoint.
HttpPost expects 0 or 1 arguments. If 0 arguments are provided, you must specify an
endpoint property method.
```javascript
stateCount|httpPost(url ...string)
```
Returns: [HTTPPostNode ](/kapacitor/v1.4/nodes/http_post_node/ )
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### InfluxDBOut
Create an influxdb output node that will store the incoming data into InfluxDB.
```javascript
stateCount|influxDBOut()
```
Returns: [InfluxDBOutNode ](/kapacitor/v1.4/nodes/influx_d_b_out_node/ )
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### Join
Join this node with other nodes. The data is joined on timestamp.
```javascript
stateCount|join(others ...Node)
```
Returns: [JoinNode ](/kapacitor/v1.4/nodes/join_node/ )
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### K8sAutoscale
Create a node that can trigger autoscale events for a kubernetes cluster.
```javascript
stateCount|k8sAutoscale()
```
Returns: [K8sAutoscaleNode ](/kapacitor/v1.4/nodes/k8s_autoscale_node/ )
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### KapacitorLoopback
Create an kapacitor loopback node that will send data back into Kapacitor as a stream.
```javascript
stateCount|kapacitorLoopback()
```
Returns: [KapacitorLoopbackNode ](/kapacitor/v1.4/nodes/kapacitor_loopback_node/ )
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### Last
Select the last point.
```javascript
stateCount|last(field string)
```
Returns: [InfluxQLNode ](/kapacitor/v1.4/nodes/influx_q_l_node/ )
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### Log
Create a node that logs all data it receives.
```javascript
stateCount|log()
```
Returns: [LogNode ](/kapacitor/v1.4/nodes/log_node/ )
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### Max
Select the maximum point.
```javascript
stateCount|max(field string)
```
Returns: [InfluxQLNode ](/kapacitor/v1.4/nodes/influx_q_l_node/ )
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### Mean
Compute the mean of the data.
```javascript
stateCount|mean(field string)
```
Returns: [InfluxQLNode ](/kapacitor/v1.4/nodes/influx_q_l_node/ )
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### Median
Compute the median of the data. Note, this method is not a selector,
if you want the median point use `.percentile(field, 50.0)` .
```javascript
stateCount|median(field string)
```
Returns: [InfluxQLNode ](/kapacitor/v1.4/nodes/influx_q_l_node/ )
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### Min
Select the minimum point.
```javascript
stateCount|min(field string)
```
Returns: [InfluxQLNode ](/kapacitor/v1.4/nodes/influx_q_l_node/ )
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### Mode
Compute the mode of the data.
```javascript
stateCount|mode(field string)
```
Returns: [InfluxQLNode ](/kapacitor/v1.4/nodes/influx_q_l_node/ )
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### MovingAverage
Compute a moving average of the last window points.
No points are emitted until the window is full.
```javascript
stateCount|movingAverage(field string, window int64)
```
Returns: [InfluxQLNode ](/kapacitor/v1.4/nodes/influx_q_l_node/ )
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### Percentile
Select a point at the given percentile. This is a selector function, no interpolation between points is performed.
```javascript
stateCount|percentile(field string, percentile float64)
```
Returns: [InfluxQLNode ](/kapacitor/v1.4/nodes/influx_q_l_node/ )
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### Sample
Create a new node that samples the incoming points or batches.
One point will be emitted every count or duration specified.
```javascript
stateCount|sample(rate interface{})
```
Returns: [SampleNode ](/kapacitor/v1.4/nodes/sample_node/ )
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### Shift
Create a new node that shifts the incoming points or batches in time.
```javascript
stateCount|shift(shift time.Duration)
```
Returns: [ShiftNode ](/kapacitor/v1.4/nodes/shift_node/ )
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### Sideload
Create a node that can load data from external sources
```javascript
stateCount|sideload()
```
Returns: [SideloadNode ](/kapacitor/v1.4/nodes/sideload_node/ )
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### Spread
Compute the difference between `min` and `max` points.
```javascript
stateCount|spread(field string)
```
Returns: [InfluxQLNode ](/kapacitor/v1.4/nodes/influx_q_l_node/ )
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### StateCount
Create a node that tracks number of consecutive points in a given state.
```javascript
stateCount|stateCount(expression ast.LambdaNode)
```
Returns: [StateCountNode ](/kapacitor/v1.4/nodes/state_count_node/ )
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### StateDuration
Create a node that tracks duration in a given state.
```javascript
stateCount|stateDuration(expression ast.LambdaNode)
```
Returns: [StateDurationNode ](/kapacitor/v1.4/nodes/state_duration_node/ )
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### Stats
Create a new stream of data that contains the internal statistics of the node.
The interval represents how often to emit the statistics based on real time.
This means the interval time is independent of the times of the data points the source node is receiving.
```javascript
stateCount|stats(interval time.Duration)
```
Returns: [StatsNode ](/kapacitor/v1.4/nodes/stats_node/ )
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### Stddev
Compute the standard deviation.
```javascript
stateCount|stddev(field string)
```
Returns: [InfluxQLNode ](/kapacitor/v1.4/nodes/influx_q_l_node/ )
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### Sum
Compute the sum of all values.
```javascript
stateCount|sum(field string)
```
Returns: [InfluxQLNode ](/kapacitor/v1.4/nodes/influx_q_l_node/ )
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### SwarmAutoscale
Create a node that can trigger autoscale events for a docker swarm cluster.
```javascript
stateCount|swarmAutoscale()
```
Returns: [SwarmAutoscaleNode ](/kapacitor/v1.4/nodes/swarm_autoscale_node/ )
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### Top
Select the top `num` points for `field` and sort by any extra tags or fields.
```javascript
stateCount|top(num int64, field string, fieldsAndTags ...string)
```
Returns: [InfluxQLNode ](/kapacitor/v1.4/nodes/influx_q_l_node/ )
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### Union
Perform the union of this node and all other given nodes.
```javascript
stateCount|union(node ...Node)
```
Returns: [UnionNode ](/kapacitor/v1.4/nodes/union_node/ )
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### Where
Create a new node that filters the data stream by a given expression.
```javascript
stateCount|where(expression ast.LambdaNode)
```
Returns: [WhereNode ](/kapacitor/v1.4/nodes/where_node/ )
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### Window
Create a new node that windows the stream by time.
NOTE: Window can only be applied to stream edges.
```javascript
stateCount|window()
```
Returns: [WindowNode ](/kapacitor/v1.4/nodes/window_node/ )
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