Trigger this action if the alarm fires.

Typically SnsAction or AutoScalingAction.

addAlarmAction

Turn this alarm into a horizontal annotation.

This is useful if you want to represent an Alarm in a non-AlarmWidget.
An `AlarmWidget` can directly show an alarm, but it can only show a
single alarm and no other metrics. Instead, you can convert the alarm to
a HorizontalAnnotation and add it as an annotation to another graph.

This might be useful if:

- You want to show multiple alarms inside a single graph, for example if
  you have both a "small margin/long period" alarm as well as a
  "large margin/short period" alarm.

- You want to show an Alarm line in a graph with multiple metrics in it.

toAnnotation

Alarm

The metric to add the alarm on.

Metric objects can be obtained from most resources, or you can construct
custom Metric objects by instantiating one.

metric

The number of periods over which data is compared to the specified threshold.

evaluationPeriods

The value against which the specified statistic is compared.

threshold

Whether the actions for this alarm are enabled.

actionsEnabled

alarmDescription

alarmName

Comparison to use to check if metric is breaching.

comparisonOperator

The number of datapoints that must be breaching to trigger the alarm.

This is used only if you are setting an "M
out of N" alarm. In that case, this value is the M. For more information, see Evaluating an Alarm in the Amazon
CloudWatch User Guide.

datapointsToAlarm

Specifies whether to evaluate the data and potentially change the alarm state if there are too few data points to be statistically significant.

Used only for alarms that are based on percentiles.

evaluateLowSampleCountPercentile

Sets how this alarm is to handle missing data points.

treatMissingData

CloudWatch Alarm that uses anomaly detection to trigger alarms.

This alarm type is specifically designed for use with anomaly detection operators
like LESS_THAN_LOWER_OR_GREATER_THAN_UPPER_THRESHOLD.

AnomalyDetectionAlarm

Comparison operator to use to check if metric is breaching.

Must be one of the anomaly detection operators:
- LESS_THAN_LOWER_OR_GREATER_THAN_UPPER_THRESHOLD
- GREATER_THAN_UPPER_THRESHOLD
- LESS_THAN_LOWER_THRESHOLD

The period over which the specified statistic is applied.

Cannot be used with `MathExpression` objects.

period

statistic

The number of standard deviations to use for the anomaly detection band.

The higher the value, the wider the band.

- Must be greater than 0. A value of 0 or negative values would not make sense in the context of calculating standard deviations.
- There is no strict maximum value defined, as standard deviations can theoretically extend infinitely. However, in practice, values beyond 5 or 6 standard deviations are rarely used, as they would result in an extremely wide anomaly detection band, potentially missing significant anomalies.

stdDevs

CompositeAlarm

Expression that specifies which other alarms are to be evaluated to determine this composite alarm's state.

alarmRule

Actions will be suppressed if the suppressor alarm is in the ALARM state.

actionsSuppressor

The maximum duration that the composite alarm waits after suppressor alarm goes out of the ALARM state.

After this time, the composite alarm performs its actions.

actionsSuppressorExtensionPeriod

The maximum duration that the composite alarm waits for the suppressor alarm to go into the ALARM state.

After this time, the composite alarm performs its actions.

actionsSuppressorWaitPeriod

compositeAlarmName

addVariable

Add a widget to the dashboard.

Widgets given in multiple calls to add() will be laid out stacked on
top of each other.

Multiple widgets added in the same call to add() will be laid out next
to each other.

addWidgets

Dashboard

Name of the dashboard.

If set, must only contain alphanumerics, dash (-) and underscore (_)

dashboardName

Interval duration for metrics. You can specify defaultInterval with the relative time (e.g. cdk.Duration.days(7)).

Both properties `defaultInterval` and `start` cannot be set at once.

defaultInterval

The end of the time range to use for each widget on the dashboard when the dashboard loads.

If you specify a value for end, you must also specify a value for start.
Specify an absolute time in the ISO 8601 format. For example, 2018-12-17T06:00:00.000Z.

Use this field to specify the period for the graphs when the dashboard loads.

Specifying `Auto` causes the period of all graphs on the dashboard to automatically adapt to the time range of the dashboard.
Specifying `Inherit` ensures that the period set for each graph is always obeyed.

periodOverride

The start of the time range to use for each widget on the dashboard.

You can specify start without specifying end to specify a relative time range that ends with the current time.
In this case, the value of start must begin with -P, and you can use M, H, D, W and M as abbreviations for
minutes, hours, days, weeks and months. For example, -PT8H shows the last 8 hours and -P3M shows the last three months.
You can also use start along with an end field, to specify an absolute time range.
When specifying an absolute time range, use the ISO 8601 format. For example, 2018-12-17T06:00:00.000Z.

Both properties `defaultInterval` and `start` cannot be set at once.

start

variables

Initial set of widgets on the dashboard.

One array represents a row of widgets.

widgets

The `AWS::CloudWatch::Alarm` type specifies an alarm and associates it with the specified metric or metric math expression.

When this operation creates an alarm, the alarm state is immediately set to `INSUFFICIENT_DATA` . The alarm is then evaluated and its state is set appropriately. Any actions associated with the new state are then executed.

When you update an existing alarm, its state is left unchanged, but the update completely overwrites the previous configuration of the alarm.

CfnAlarm

Indicates whether actions should be executed during any changes to the alarm state.

The default is TRUE.

The list of actions to execute when this alarm transitions into an ALARM state from any other state.

Specify each action as an Amazon Resource Name (ARN). For more information about creating alarms and the actions that you can specify, see [PutMetricAlarm](https://docs.aws.amazon.com/AmazonCloudWatch/latest/APIReference/API_PutMetricAlarm.html) in the *Amazon CloudWatch API Reference* .

alarmActions

The name of the alarm.

If you don't specify a name, CloudFormation generates a unique physical ID and uses that ID for the alarm name.

> If you specify a name, you cannot perform updates that require replacement of this resource. You can perform updates that require no or some interruption. If you must replace the resource, specify a new name.

The arithmetic operation to use when comparing the specified statistic and threshold.

The specified statistic value is used as the first operand.

The number of datapoints that must be breaching to trigger the alarm.

This is used only if you are setting an "M out of N" alarm. In that case, this value is the M, and the value that you set for `EvaluationPeriods` is the N value. For more information, see [Evaluating an Alarm](https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/AlarmThatSendsEmail.html#alarm-evaluation) in the *Amazon CloudWatch User Guide* .

If you omit this parameter, CloudWatch uses the same value here that you set for `EvaluationPeriods` , and the alarm goes to alarm state if that many consecutive periods are breaching.

The dimensions for the metric associated with the alarm.

For an alarm based on a math expression, you can't specify `Dimensions` . Instead, you use `Metrics` .

dimensions

Used only for alarms based on percentiles.

If `ignore` , the alarm state does not change during periods with too few data points to be statistically significant. If `evaluate` or this parameter is not used, the alarm is always evaluated and possibly changes state no matter how many data points are available.

The number of periods over which data is compared to the specified threshold.

If you are setting an alarm that requires that a number of consecutive data points be breaching to trigger the alarm, this value specifies that number. If you are setting an "M out of N" alarm, this value is the N, and `DatapointsToAlarm` is the M.

For more information, see [Evaluating an Alarm](https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/AlarmThatSendsEmail.html#alarm-evaluation) in the *Amazon CloudWatch User Guide* .

The percentile statistic for the metric associated with the alarm. Specify a value between p0.0 and p100.

For an alarm based on a metric, you must specify either `Statistic` or `ExtendedStatistic` but not both.

For an alarm based on a math expression, you can't specify `ExtendedStatistic` . Instead, you use `Metrics` .

extendedStatistic

The actions to execute when this alarm transitions to the `INSUFFICIENT_DATA` state from any other state.

Each action is specified as an Amazon Resource Name (ARN).

insufficientDataActions

The name of the metric associated with the alarm.

This is required for an alarm based on a metric. For an alarm based on a math expression, you use `Metrics` instead and you can't specify `MetricName` .

metricName

An array that enables you to create an alarm based on the result of a metric math expression.

Each item in the array either retrieves a metric or performs a math expression.

If you specify the `Metrics` parameter, you cannot specify `MetricName` , `Dimensions` , `Period` , `Namespace` , `Statistic` , `ExtendedStatistic` , or `Unit` .

metrics

The namespace of the metric associated with the alarm.

This is required for an alarm based on a metric. For an alarm based on a math expression, you can't specify `Namespace` and you use `Metrics` instead.

For a list of namespaces for metrics from AWS services, see [AWS Services That Publish CloudWatch Metrics.](https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/aws-services-cloudwatch-metrics.html)

namespace

The actions to execute when this alarm transitions to the `OK` state from any other state.

Each action is specified as an Amazon Resource Name (ARN).

okActions

The period, in seconds, over which the statistic is applied.

This is required for an alarm based on a metric. Valid values are 10, 20, 30, 60, and any multiple of 60.

For an alarm based on a math expression, you can't specify `Period` , and instead you use the `Metrics` parameter.

*Minimum:* 10

The statistic for the metric associated with the alarm, other than percentile. For percentile statistics, use `ExtendedStatistic` .

For an alarm based on a metric, you must specify either `Statistic` or `ExtendedStatistic` but not both.

For an alarm based on a math expression, you can't specify `Statistic` . Instead, you use `Metrics` .

A list of key-value pairs to associate with the alarm.

You can associate as many as 50 tags with an alarm. To be able to associate tags with the alarm when you create the alarm, you must have the `cloudwatch:TagResource` permission.

Tags can help you organize and categorize your resources. You can also use them to scope user permissions by granting a user permission to access or change only resources with certain tag values.

thresholdMetricId

Sets how this alarm is to handle missing data points.

Valid values are `breaching` , `notBreaching` , `ignore` , and `missing` . For more information, see [Configuring How CloudWatch Alarms Treat Missing Data](https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/AlarmThatSendsEmail.html#alarms-and-missing-data) in the *Amazon CloudWatch User Guide* .

If you omit this parameter, the default behavior of `missing` is used.

The unit of the metric associated with the alarm.

Specify this only if you are creating an alarm based on a single metric. Do not specify this if you are specifying a `Metrics` array.

You can specify the following values: Seconds, Microseconds, Milliseconds, Bytes, Kilobytes, Megabytes, Gigabytes, Terabytes, Bits, Kilobits, Megabits, Gigabits, Terabits, Percent, Count, Bytes/Second, Kilobytes/Second, Megabytes/Second, Gigabytes/Second, Terabytes/Second, Bits/Second, Kilobits/Second, Megabits/Second, Gigabits/Second, Terabits/Second, Count/Second, or None.

unit

Resource Type definition for AWS::CloudWatch::AlarmMuteRule that allows defining a rule and targeting alarms to mute their actions during the specified window.

CfnAlarmMuteRule

rule

description

The date, with the same timezone offset as "ScheduleTimezone" after which the alarm mute rule will be expired.

expireDate

muteTargets

name

The date, with the same timezone offset as "ScheduleTimezone", after which the alarm mute rule will become active.

startDate

An array of key-value pairs to apply to this resource.

The `AWS::CloudWatch::AnomalyDetector` type specifies an anomaly detection band for a certain metric and statistic.

The band represents the expected "normal" range for the metric values. Anomaly detection bands can be used for visualization of a metric's expected values, and for alarms.

For more information see [Using CloudWatch anomaly detection.](https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/CloudWatch_Anomaly_Detection.html) .

CfnAnomalyDetector

Specifies details about how the anomaly detection model is to be trained, including time ranges to exclude when training and updating the model.

The configuration can also include the time zone to use for the metric.

configuration

The dimensions of the metric associated with the anomaly detection band.

Use this object to include parameters to provide information about your metric to CloudWatch to help it build more accurate anomaly detection models.

Currently, it includes the `PeriodicSpikes` parameter.

metricCharacteristics

The CloudWatch metric math expression for this anomaly detector.

metricMathAnomalyDetector

The name of the metric associated with the anomaly detection band.

The namespace of the metric associated with the anomaly detection band.

The CloudWatch metric and statistic for this anomaly detector.

singleMetricAnomalyDetector

The statistic of the metric associated with the anomaly detection band.

stat

The `AWS::CloudWatch::CompositeAlarm` type creates or updates a composite alarm.

When you create a composite alarm, you specify a rule expression for the alarm that takes into account the alarm states of other alarms that you have created. The composite alarm goes into ALARM state only if all conditions of the rule are met.

The alarms specified in a composite alarm's rule expression can include metric alarms and other composite alarms.

Using composite alarms can reduce alarm noise. You can create multiple metric alarms, and also create a composite alarm and set up alerts only for the composite alarm. For example, you could create a composite alarm that goes into ALARM state only when more than one of the underlying metric alarms are in ALARM state.

When this operation creates an alarm, the alarm state is immediately set to INSUFFICIENT_DATA. The alarm is then evaluated and its state is set appropriately. Any actions associated with the new state are then executed. For a composite alarm, this initial time after creation is the only time that the alarm can be in INSUFFICIENT_DATA state.

When you update an existing alarm, its state is left unchanged, but the update completely overwrites the previous configuration of the alarm.

CfnCompositeAlarm

An expression that specifies which other alarms are to be evaluated to determine this composite alarm's state.

For each alarm that you reference, you designate a function that specifies whether that alarm needs to be in ALARM state, OK state, or INSUFFICIENT_DATA state. You can use operators (AND, OR and NOT) to combine multiple functions in a single expression. You can use parenthesis to logically group the functions in your expression.

You can use either alarm names or ARNs to reference the other alarms that are to be evaluated.

Functions can include the following:

- ALARM("alarm-name or alarm-ARN") is TRUE if the named alarm is in ALARM state.
- OK("alarm-name or alarm-ARN") is TRUE if the named alarm is in OK state.
- INSUFFICIENT_DATA("alarm-name or alarm-ARN") is TRUE if the named alarm is in INSUFFICIENT_DATA state.
- TRUE always evaluates to TRUE.
- FALSE always evaluates to FALSE.

TRUE and FALSE are useful for testing a complex AlarmRule structure, and for testing your alarm actions.

For more information about `AlarmRule` syntax, see [PutCompositeAlarm](https://docs.aws.amazon.com/AmazonCloudWatch/latest/APIReference/API_PutCompositeAlarm.html) in the *Amazon CloudWatch API Reference* .

Indicates whether actions should be executed during any changes to the alarm state of the composite alarm.

The default is TRUE.

Actions will be suppressed if the suppressor alarm is in the `ALARM` state.

`ActionsSuppressor` can be an AlarmName or an Amazon Resource Name (ARN) from an existing alarm.

The maximum time in seconds that the composite alarm waits after suppressor alarm goes out of the `ALARM` state.

After this time, the composite alarm performs its actions.

> `ExtensionPeriod` is required only when `ActionsSuppressor` is specified.

The maximum time in seconds that the composite alarm waits for the suppressor alarm to go into the `ALARM` state.

After this time, the composite alarm performs its actions.

> `WaitPeriod` is required only when `ActionsSuppressor` is specified.

The actions to execute when this alarm transitions to the ALARM state from any other state.

Each action is specified as an Amazon Resource Name (ARN). For more information about creating alarms and the actions that you can specify, see [PutCompositeAlarm](https://docs.aws.amazon.com/AmazonCloudWatch/latest/APIReference/API_PutCompositeAlarm.html) in the *Amazon CloudWatch API Reference* .

The name for the composite alarm.

This name must be unique within your AWS account.

The actions to execute when this alarm transitions to the INSUFFICIENT_DATA state from any other state.

Each action is specified as an Amazon Resource Name (ARN). For more information about creating alarms and the actions that you can specify, see [PutCompositeAlarm](https://docs.aws.amazon.com/AmazonCloudWatch/latest/APIReference/API_PutCompositeAlarm.html) in the *Amazon CloudWatch API Reference* .

The actions to execute when this alarm transitions to the OK state from any other state.

Each action is specified as an Amazon Resource Name (ARN). For more information about creating alarms and the actions that you can specify, see [PutCompositeAlarm](https://docs.aws.amazon.com/AmazonCloudWatch/latest/APIReference/API_PutCompositeAlarm.html) in the *Amazon CloudWatch API Reference* .

The `AWS::CloudWatch::Dashboard` resource specifies an Amazon CloudWatch dashboard.

A dashboard is a customizable home page in the CloudWatch console that you can use to monitor your AWS resources in a single view.

All dashboards in your account are global, not region-specific.

CfnDashboard

The detailed information about the dashboard in JSON format, including the widgets to include and their location on the dashboard.

This parameter is required.

For more information about the syntax, see [Dashboard Body Structure and Syntax](https://docs.aws.amazon.com/AmazonCloudWatch/latest/APIReference/CloudWatch-Dashboard-Body-Structure.html) .

dashboardBody

The name of the dashboard.

The name must be between 1 and 255 characters. If you do not specify a name, one will be generated automatically.

Creates or updates a Contributor Insights rule.

Rules evaluate log events in a CloudWatch Logs log group, enabling you to find contributor data for the log events in that log group. For more information, see [Using Contributor Insights to Analyze High-Cardinality Data](https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/ContributorInsights.html) in the *Amazon CloudWatch User Guide* .

CfnInsightRule

The definition of the rule, as a JSON object.

For details about the syntax, see [Contributor Insights Rule Syntax](https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/ContributorInsights-RuleSyntax.html) in the *Amazon CloudWatch User Guide* .

ruleBody

ruleName

The current state of the rule.

Valid values are `ENABLED` and `DISABLED` .

ruleState

Determines whether the rules is evaluated on transformed versions of logs.

Valid values are `TRUE` and `FALSE` .

applyOnTransformedLogs

A list of key-value pairs to associate with the Contributor Insights rule.

You can associate as many as 50 tags with a rule.

Tags can help you organize and categorize your resources. For more information, see [Tagging Your Amazon CloudWatch Resources](https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/CloudWatch-Tagging.html) .

To be able to associate tags with a rule, you must have the `cloudwatch:TagResource` permission in addition to the `cloudwatch:PutInsightRule` permission.

Creates or updates a metric stream.

Metrics streams can automatically stream CloudWatch metrics to AWS destinations including Amazon S3 and to many third-party solutions. For more information, see [Metric streams](https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/CloudWatch-Metric-Streams.html) .

To create a metric stream, you must be logged on to an account that has the `iam:PassRole` permission and either the *CloudWatchFullAccess* policy or the `cloudwatch:PutMetricStream` permission.

When you create or update a metric stream, you choose one of the following:

- Stream metrics from all metric namespaces in the account.
- Stream metrics from all metric namespaces in the account, except for the namespaces that you list in `ExcludeFilters` .
- Stream metrics from only the metric namespaces that you list in `IncludeFilters` .

When you create a metric stream, the stream is created in the `running` state. If you update an existing metric stream, the state does not change.

If you create a metric stream in an account that has been set up as a monitoring account in CloudWatch cross-account observability, you can choose whether to include metrics from linked source accounts in the metric stream.

CfnMetricStream

The ARN of the Amazon Kinesis Firehose delivery stream to use for this metric stream.

This Amazon Kinesis Firehose delivery stream must already exist and must be in the same account as the metric stream.

firehoseArn

The output format for the stream.

Valid values are `json` , `opentelemetry1.0` and `opentelemetry0.7` For more information about metric stream output formats, see [Metric streams output formats](https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/CloudWatch-metric-streams-formats.html) .

This parameter is required.

outputFormat

The ARN of an IAM role that this metric stream will use to access Amazon Kinesis Firehose resources.

This IAM role must already exist and must be in the same account as the metric stream. This IAM role must include the `firehose:PutRecord` and `firehose:PutRecordBatch` permissions.

roleArn

If you specify this parameter, the stream sends metrics from all metric namespaces except for the namespaces that you specify here.

You cannot specify both `IncludeFilters` and `ExcludeFilters` in the same metric stream.

When you modify the `IncludeFilters` or `ExcludeFilters` of an existing metric stream in any way, the metric stream is effectively restarted, so after such a change you will get only the datapoints that have a timestamp after the time of the update.

excludeFilters

If you specify this parameter, the stream sends only the metrics from the metric namespaces that you specify here.

You cannot specify both `IncludeFilters` and `ExcludeFilters` in the same metric stream.

When you modify the `IncludeFilters` or `ExcludeFilters` of an existing metric stream in any way, the metric stream is effectively restarted, so after such a change you will get only the datapoints that have a timestamp after the time of the update.

includeFilters

If you are creating a metric stream in a monitoring account, specify `true` to include metrics from source accounts that are linked to this monitoring account, in the metric stream.

The default is `false` .

For more information about linking accounts, see [CloudWatch cross-account observability](https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/CloudWatch-Unified-Cross-Account.html)

includeLinkedAccountsMetrics

If you are creating a new metric stream, this is the name for the new stream.

The name must be different than the names of other metric streams in this account and Region.

If you are updating a metric stream, specify the name of that stream here.

By default, a metric stream always sends the MAX, MIN, SUM, and SAMPLECOUNT statistics for each metric that is streamed.

You can use this parameter to have the metric stream also send additional statistics in the stream. This array can have up to 100 members.

For each entry in this array, you specify one or more metrics and the list of additional statistics to stream for those metrics. The additional statistics that you can stream depend on the stream's `OutputFormat` . If the `OutputFormat` is `json` , you can stream any additional statistic that is supported by CloudWatch , listed in [CloudWatch statistics definitions](https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/Statistics-definitions.html) . If the `OutputFormat` is OpenTelemetry, you can stream percentile statistics.

statisticsConfigurations

An array of key-value pairs to apply to the metric stream.

For more information, see [Tag](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-properties-resource-tags.html) .

Amazon CloudWatch

L2 Constructs4

Alarm

AnomalyDetectionAlarm

CompositeAlarm

Dashboard

L1 Constructs7

CfnAlarm

CfnAlarmMuteRule

CfnAnomalyDetector

CfnCompositeAlarm

CfnDashboard

CfnInsightRule

CfnMetricStream

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