---
title: NoOpNode (Kapacitor TICKscript node)
description: NoOpNode does not perform any operation, but is automatically appended to any node that is a source for a StatsNode and does not have any children.
note: Auto generated by tickdoc

menu:
  kapacitor_1_4:
    name: NoOpNode
    identifier: no_op_node
    weight: 210
    parent: TICKscript nodes
---
### Constructor

| Chaining Method | Description |
|:---------|:---------|
| **[noOp](#descr)** | Has no constructor signature. |
### Property Methods
This node has no properties that can be set.


### Chaining Methods
[Alert](/kapacitor/v1.4/nodes/no_op_node/#alert), [Barrier](/kapacitor/v1.4/nodes/no_op_node/#barrier), [Bottom](/kapacitor/v1.4/nodes/no_op_node/#bottom), [Combine](/kapacitor/v1.4/nodes/no_op_node/#combine), [Count](/kapacitor/v1.4/nodes/no_op_node/#count), [CumulativeSum](/kapacitor/v1.4/nodes/no_op_node/#cumulativesum), [Deadman](/kapacitor/v1.4/nodes/no_op_node/#deadman), [Default](/kapacitor/v1.4/nodes/no_op_node/#default), [Delete](/kapacitor/v1.4/nodes/no_op_node/#delete), [Derivative](/kapacitor/v1.4/nodes/no_op_node/#derivative), [Difference](/kapacitor/v1.4/nodes/no_op_node/#difference), [Distinct](/kapacitor/v1.4/nodes/no_op_node/#distinct), [Ec2Autoscale](/kapacitor/v1.4/nodes/no_op_node/#ec2autoscale), [Elapsed](/kapacitor/v1.4/nodes/no_op_node/#elapsed), [Eval](/kapacitor/v1.4/nodes/no_op_node/#eval), [First](/kapacitor/v1.4/nodes/no_op_node/#first), [Flatten](/kapacitor/v1.4/nodes/no_op_node/#flatten), [GroupBy](/kapacitor/v1.4/nodes/no_op_node/#groupby), [HoltWinters](/kapacitor/v1.4/nodes/no_op_node/#holtwinters), [HoltWintersWithFit](/kapacitor/v1.4/nodes/no_op_node/#holtwinterswithfit), [HttpOut](/kapacitor/v1.4/nodes/no_op_node/#httpout), [HttpPost](/kapacitor/v1.4/nodes/no_op_node/#httppost), [InfluxDBOut](/kapacitor/v1.4/nodes/no_op_node/#influxdbout), [Join](/kapacitor/v1.4/nodes/no_op_node/#join), [K8sAutoscale](/kapacitor/v1.4/nodes/no_op_node/#k8sautoscale), [KapacitorLoopback](/kapacitor/v1.4/nodes/no_op_node/#kapacitorloopback), [Last](/kapacitor/v1.4/nodes/no_op_node/#last), [Log](/kapacitor/v1.4/nodes/no_op_node/#log), [Max](/kapacitor/v1.4/nodes/no_op_node/#max), [Mean](/kapacitor/v1.4/nodes/no_op_node/#mean), [Median](/kapacitor/v1.4/nodes/no_op_node/#median), [Min](/kapacitor/v1.4/nodes/no_op_node/#min), [Mode](/kapacitor/v1.4/nodes/no_op_node/#mode), [MovingAverage](/kapacitor/v1.4/nodes/no_op_node/#movingaverage), [Percentile](/kapacitor/v1.4/nodes/no_op_node/#percentile), [Sample](/kapacitor/v1.4/nodes/no_op_node/#sample), [Shift](/kapacitor/v1.4/nodes/no_op_node/#shift), [Sideload](/kapacitor/v1.4/nodes/no_op_node/#sideload), [Spread](/kapacitor/v1.4/nodes/no_op_node/#spread), [StateCount](/kapacitor/v1.4/nodes/no_op_node/#statecount), [StateDuration](/kapacitor/v1.4/nodes/no_op_node/#stateduration), [Stats](/kapacitor/v1.4/nodes/no_op_node/#stats), [Stddev](/kapacitor/v1.4/nodes/no_op_node/#stddev), [Sum](/kapacitor/v1.4/nodes/no_op_node/#sum), [SwarmAutoscale](/kapacitor/v1.4/nodes/no_op_node/#swarmautoscale), [Top](/kapacitor/v1.4/nodes/no_op_node/#top), [Union](/kapacitor/v1.4/nodes/no_op_node/#union), [Where](/kapacitor/v1.4/nodes/no_op_node/#where), [Window](/kapacitor/v1.4/nodes/no_op_node/#window)
<a id='descr'/><hr/><br/>
### Description

A node that does not perform any operation.

*Do not use this node in a TICKscript there should be no need for it.*

If a node does not have any children, then its emitted count remains zero.
Using a [NoOpNode](/kapacitor/v1.4/nodes/no_op_node/) is a work around so that statistics are accurately reported
for nodes with no real children.
A [NoOpNode](/kapacitor/v1.4/nodes/no_op_node/) is automatically appended to any node that is a source for a [StatsNode](/kapacitor/v1.4/nodes/stats_node/)
and does not have any children.


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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
noOp|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
noOp|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
noOp|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
noOp|combine(expressions ...ast.LambdaNode)
```

Returns: [CombineNode](/kapacitor/v1.4/nodes/combine_node/)

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### Count

Count the number of points.


```javascript
noOp|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
noOp|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
noOp|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
noOp|default()
```

Returns: [DefaultNode](/kapacitor/v1.4/nodes/default_node/)

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### Delete

Create a node that can delete tags or fields.


```javascript
noOp|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
noOp|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
noOp|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
noOp|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
noOp|ec2Autoscale()
```

Returns: [Ec2AutoscaleNode](/kapacitor/v1.4/nodes/ec2_autoscale_node/)

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### Elapsed

Compute the elapsed time between points


```javascript
noOp|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
noOp|eval(expressions ...ast.LambdaNode)
```

Returns: [EvalNode](/kapacitor/v1.4/nodes/eval_node/)

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### First

Select the first point.


```javascript
noOp|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
noOp|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
noOp|groupBy(tag ...interface{})
```

Returns: [GroupByNode](/kapacitor/v1.4/nodes/group_by_node/)

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### HoltWinters

Compute the holt-winters (/{{< latest "influxdb" "v1" >}}/query_language/functions/#holt-winters) forecast of a data set.


```javascript
noOp|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

Compute the holt-winters (/{{< latest "influxdb" "v1" >}}/query_language/functions/#holt-winters) forecast of a data set.
This method also outputs all the points used to fit the data in addition to the forecasted data.


```javascript
noOp|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
noOp|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
noOp|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
noOp|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
noOp|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
noOp|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
noOp|kapacitorLoopback()
```

Returns: [KapacitorLoopbackNode](/kapacitor/v1.4/nodes/kapacitor_loopback_node/)

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### Last

Select the last point.


```javascript
noOp|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
noOp|log()
```

Returns: [LogNode](/kapacitor/v1.4/nodes/log_node/)

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### Max

Select the maximum point.


```javascript
noOp|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
noOp|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
noOp|median(field string)
```

Returns: [InfluxQLNode](/kapacitor/v1.4/nodes/influx_q_l_node/)

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### Min

Select the minimum point.


```javascript
noOp|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
noOp|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
noOp|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
noOp|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
noOp|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
noOp|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
noOp|sideload()
```

Returns: [SideloadNode](/kapacitor/v1.4/nodes/sideload_node/)

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### Spread

Compute the difference between `min` and `max` points.


```javascript
noOp|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
noOp|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
noOp|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
noOp|stats(interval time.Duration)
```

Returns: [StatsNode](/kapacitor/v1.4/nodes/stats_node/)

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### Stddev

Compute the standard deviation.


```javascript
noOp|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
noOp|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
noOp|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
noOp|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
noOp|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
noOp|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
noOp|window()
```

Returns: [WindowNode](/kapacitor/v1.4/nodes/window_node/)

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