class CfnAlarm (construct)
Language | Type name |
---|---|
![]() | Amazon.CDK.AWS.CloudWatch.CfnAlarm |
![]() | github.com/aws/aws-cdk-go/awscdk/v2/awscloudwatch#CfnAlarm |
![]() | software.amazon.awscdk.services.cloudwatch.CfnAlarm |
![]() | aws_cdk.aws_cloudwatch.CfnAlarm |
![]() | aws-cdk-lib » aws_cloudwatch » CfnAlarm |
Implements
IConstruct
, IDependable
, IInspectable
, ITaggable
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.
See also: http://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-resource-cloudwatch-alarm.html
Example
// The code below shows an example of how to instantiate this type.
// The values are placeholders you should change.
import { aws_cloudwatch as cloudwatch } from 'aws-cdk-lib';
const cfnAlarm = new cloudwatch.CfnAlarm(this, 'MyCfnAlarm', {
comparisonOperator: 'comparisonOperator',
evaluationPeriods: 123,
// the properties below are optional
actionsEnabled: false,
alarmActions: ['alarmActions'],
alarmDescription: 'alarmDescription',
alarmName: 'alarmName',
datapointsToAlarm: 123,
dimensions: [{
name: 'name',
value: 'value',
}],
evaluateLowSampleCountPercentile: 'evaluateLowSampleCountPercentile',
extendedStatistic: 'extendedStatistic',
insufficientDataActions: ['insufficientDataActions'],
metricName: 'metricName',
metrics: [{
id: 'id',
// the properties below are optional
accountId: 'accountId',
expression: 'expression',
label: 'label',
metricStat: {
metric: {
dimensions: [{
name: 'name',
value: 'value',
}],
metricName: 'metricName',
namespace: 'namespace',
},
period: 123,
stat: 'stat',
// the properties below are optional
unit: 'unit',
},
period: 123,
returnData: false,
}],
namespace: 'namespace',
okActions: ['okActions'],
period: 123,
statistic: 'statistic',
tags: [{
key: 'key',
value: 'value',
}],
threshold: 123,
thresholdMetricId: 'thresholdMetricId',
treatMissingData: 'treatMissingData',
unit: 'unit',
});
Initializer
new CfnAlarm(scope: Construct, id: string, props: CfnAlarmProps)
Parameters
- scope
Construct
— Scope in which this resource is defined. - id
string
— Construct identifier for this resource (unique in its scope). - props
Cfn
— Resource properties.Alarm Props
Construct Props
Name | Type | Description |
---|---|---|
comparison | string | The arithmetic operation to use when comparing the specified statistic and threshold. |
evaluation | number | The number of periods over which data is compared to the specified threshold. |
actions | boolean | IResolvable | Indicates whether actions should be executed during any changes to the alarm state. |
alarm | string[] | The list of actions to execute when this alarm transitions into an ALARM state from any other state. |
alarm | string | The description of the alarm. |
alarm | string | The name of the alarm. |
datapoints | number | The number of datapoints that must be breaching to trigger the alarm. |
dimensions? | IResolvable | IResolvable | Dimension [] | The dimensions for the metric associated with the alarm. |
evaluate | string | Used only for alarms based on percentiles. |
extended | string | The percentile statistic for the metric associated with the alarm. Specify a value between p0.0 and p100. |
insufficient | string[] | The actions to execute when this alarm transitions to the INSUFFICIENT_DATA state from any other state. |
metric | string | The name of the metric associated with the alarm. |
metrics? | IResolvable | IResolvable | Metric [] | An array that enables you to create an alarm based on the result of a metric math expression. |
namespace? | string | The namespace of the metric associated with the alarm. |
ok | string[] | The actions to execute when this alarm transitions to the OK state from any other state. |
period? | number | The period, in seconds, over which the statistic is applied. |
statistic? | string | The statistic for the metric associated with the alarm, other than percentile. For percentile statistics, use ExtendedStatistic . |
tags? | Cfn [] | A list of key-value pairs to associate with the alarm. |
threshold? | number | The value to compare with the specified statistic. |
threshold | string | In an alarm based on an anomaly detection model, this is the ID of the ANOMALY_DETECTION_BAND function used as the threshold for the alarm. |
treat | string | Sets how this alarm is to handle missing data points. |
unit? | string | The unit of the metric associated with the alarm. |
comparisonOperator
Type:
string
The arithmetic operation to use when comparing the specified statistic and threshold.
The specified statistic value is used as the first operand.
evaluationPeriods
Type:
number
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 in the Amazon CloudWatch User Guide .
actionsEnabled?
Type:
boolean |
IResolvable
(optional, default: true)
Indicates whether actions should be executed during any changes to the alarm state.
The default is TRUE.
alarmActions?
Type:
string[]
(optional)
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 in the Amazon CloudWatch API Reference .
alarmDescription?
Type:
string
(optional)
The description of the alarm.
alarmName?
Type:
string
(optional)
The name of the alarm.
If you don't specify a name, AWS 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.
datapointsToAlarm?
Type:
number
(optional)
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 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.
dimensions?
Type:
IResolvable
|
IResolvable
|
Dimension
[]
(optional)
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
.
evaluateLowSampleCountPercentile?
Type:
string
(optional)
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.
extendedStatistic?
Type:
string
(optional)
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
.
insufficientDataActions?
Type:
string[]
(optional)
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).
metricName?
Type:
string
(optional)
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
.
metrics?
Type:
IResolvable
|
IResolvable
|
Metric
[]
(optional)
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
.
namespace?
Type:
string
(optional)
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.
okActions?
Type:
string[]
(optional)
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).
period?
Type:
number
(optional)
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
statistic?
Type:
string
(optional)
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
.
tags?
Type:
Cfn
[]
(optional)
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.
threshold?
Type:
number
(optional)
The value to compare with the specified statistic.
thresholdMetricId?
Type:
string
(optional)
In an alarm based on an anomaly detection model, this is the ID of the ANOMALY_DETECTION_BAND
function used as the threshold for the alarm.
treatMissingData?
Type:
string
(optional)
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 in the Amazon CloudWatch User Guide .
If you omit this parameter, the default behavior of missing
is used.
unit?
Type:
string
(optional)
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.
Properties
Name | Type | Description |
---|---|---|
attr | string | The ARN of the CloudWatch alarm, such as arn:aws:cloudwatch:us-west-2:123456789012:alarm:myCloudWatchAlarm-CPUAlarm-UXMMZK36R55Z . |
cdk | Tag | Tag Manager which manages the tags for this resource. |
cfn | ICfn | Options for this resource, such as condition, update policy etc. |
cfn | { [string]: any } | |
cfn | string | AWS resource type. |
comparison | string | The arithmetic operation to use when comparing the specified statistic and threshold. |
creation | string[] | |
evaluation | number | The number of periods over which data is compared to the specified threshold. |
logical | string | The logical ID for this CloudFormation stack element. |
node | Node | The tree node. |
ref | string | Return a string that will be resolved to a CloudFormation { Ref } for this element. |
stack | Stack | The stack in which this element is defined. |
actions | boolean | IResolvable | Indicates whether actions should be executed during any changes to the alarm state. |
alarm | string[] | The list of actions to execute when this alarm transitions into an ALARM state from any other state. |
alarm | string | The description of the alarm. |
alarm | string | The name of the alarm. |
datapoints | number | The number of datapoints that must be breaching to trigger the alarm. |
dimensions? | IResolvable | IResolvable | Dimension [] | The dimensions for the metric associated with the alarm. |
evaluate | string | Used only for alarms based on percentiles. |
extended | string | The percentile statistic for the metric associated with the alarm. |
insufficient | string[] | The actions to execute when this alarm transitions to the INSUFFICIENT_DATA state from any other state. |
metric | string | The name of the metric associated with the alarm. |
metrics? | IResolvable | IResolvable | Metric [] | An array that enables you to create an alarm based on the result of a metric math expression. |
namespace? | string | The namespace of the metric associated with the alarm. |
ok | string[] | The actions to execute when this alarm transitions to the OK state from any other state. |
period? | number | The period, in seconds, over which the statistic is applied. |
statistic? | string | The statistic for the metric associated with the alarm, other than percentile. |
tags? | Cfn [] | A list of key-value pairs to associate with the alarm. |
threshold? | number | The value to compare with the specified statistic. |
threshold | string | In an alarm based on an anomaly detection model, this is the ID of the ANOMALY_DETECTION_BAND function used as the threshold for the alarm. |
treat | string | Sets how this alarm is to handle missing data points. |
unit? | string | The unit of the metric associated with the alarm. |
static CFN_RESOURCE_TYPE_NAME | string | The CloudFormation resource type name for this resource class. |
attrArn
Type:
string
The ARN of the CloudWatch alarm, such as arn:aws:cloudwatch:us-west-2:123456789012:alarm:myCloudWatchAlarm-CPUAlarm-UXMMZK36R55Z
.
cdkTagManager
Type:
Tag
Tag Manager which manages the tags for this resource.
cfnOptions
Type:
ICfn
Options for this resource, such as condition, update policy etc.
cfnProperties
Type:
{ [string]: any }
cfnResourceType
Type:
string
AWS resource type.
comparisonOperator
Type:
string
The arithmetic operation to use when comparing the specified statistic and threshold.
creationStack
Type:
string[]
evaluationPeriods
Type:
number
The number of periods over which data is compared to the specified threshold.
logicalId
Type:
string
The logical ID for this CloudFormation stack element.
The logical ID of the element is calculated from the path of the resource node in the construct tree.
To override this value, use overrideLogicalId(newLogicalId)
.
node
Type:
Node
The tree node.
ref
Type:
string
Return a string that will be resolved to a CloudFormation { Ref }
for this element.
If, by any chance, the intrinsic reference of a resource is not a string, you could
coerce it to an IResolvable through Lazy.any({ produce: resource.ref })
.
stack
Type:
Stack
The stack in which this element is defined.
CfnElements must be defined within a stack scope (directly or indirectly).
actionsEnabled?
Type:
boolean |
IResolvable
(optional)
Indicates whether actions should be executed during any changes to the alarm state.
alarmActions?
Type:
string[]
(optional)
The list of actions to execute when this alarm transitions into an ALARM state from any other state.
alarmDescription?
Type:
string
(optional)
The description of the alarm.
alarmName?
Type:
string
(optional)
The name of the alarm.
datapointsToAlarm?
Type:
number
(optional)
The number of datapoints that must be breaching to trigger the alarm.
dimensions?
Type:
IResolvable
|
IResolvable
|
Dimension
[]
(optional)
The dimensions for the metric associated with the alarm.
evaluateLowSampleCountPercentile?
Type:
string
(optional)
Used only for alarms based on percentiles.
extendedStatistic?
Type:
string
(optional)
The percentile statistic for the metric associated with the alarm.
Specify a value between p0.0 and p100.
insufficientDataActions?
Type:
string[]
(optional)
The actions to execute when this alarm transitions to the INSUFFICIENT_DATA
state from any other state.
metricName?
Type:
string
(optional)
The name of the metric associated with the alarm.
metrics?
Type:
IResolvable
|
IResolvable
|
Metric
[]
(optional)
An array that enables you to create an alarm based on the result of a metric math expression.
namespace?
Type:
string
(optional)
The namespace of the metric associated with the alarm.
okActions?
Type:
string[]
(optional)
The actions to execute when this alarm transitions to the OK
state from any other state.
period?
Type:
number
(optional)
The period, in seconds, over which the statistic is applied.
statistic?
Type:
string
(optional)
The statistic for the metric associated with the alarm, other than percentile.
For percentile statistics, use ExtendedStatistic
.
tags?
Type:
Cfn
[]
(optional)
A list of key-value pairs to associate with the alarm.
threshold?
Type:
number
(optional)
The value to compare with the specified statistic.
thresholdMetricId?
Type:
string
(optional)
In an alarm based on an anomaly detection model, this is the ID of the ANOMALY_DETECTION_BAND
function used as the threshold for the alarm.
treatMissingData?
Type:
string
(optional)
Sets how this alarm is to handle missing data points.
unit?
Type:
string
(optional)
The unit of the metric associated with the alarm.
static CFN_RESOURCE_TYPE_NAME
Type:
string
The CloudFormation resource type name for this resource class.
Methods
Name | Description |
---|---|
add | Syntactic sugar for addOverride(path, undefined) . |
add | Indicates that this resource depends on another resource and cannot be provisioned unless the other resource has been successfully provisioned. |
add | Indicates that this resource depends on another resource and cannot be provisioned unless the other resource has been successfully provisioned. |
add | Add a value to the CloudFormation Resource Metadata. |
add | Adds an override to the synthesized CloudFormation resource. |
add | Adds an override that deletes the value of a property from the resource definition. |
add | Adds an override to a resource property. |
apply | Sets the deletion policy of the resource based on the removal policy specified. |
get | Returns a token for an runtime attribute of this resource. |
get | Retrieve a value value from the CloudFormation Resource Metadata. |
inspect(inspector) | Examines the CloudFormation resource and discloses attributes. |
obtain | Retrieves an array of resources this resource depends on. |
obtain | Get a shallow copy of dependencies between this resource and other resources in the same stack. |
override | Overrides the auto-generated logical ID with a specific ID. |
remove | Indicates that this resource no longer depends on another resource. |
replace | Replaces one dependency with another. |
to | Returns a string representation of this construct. |
protected render |
addDeletionOverride(path)
public addDeletionOverride(path: string): void
Parameters
- path
string
— The path of the value to delete.
Syntactic sugar for addOverride(path, undefined)
.
addDependency(target)
public addDependency(target: CfnResource): void
Parameters
- target
Cfn
Resource
Indicates that this resource depends on another resource and cannot be provisioned unless the other resource has been successfully provisioned.
This can be used for resources across stacks (or nested stack) boundaries and the dependency will automatically be transferred to the relevant scope.
addDependsOn(target)
public addDependsOn(target: CfnResource): void
⚠️ Deprecated: use addDependency
Parameters
- target
Cfn
Resource
Indicates that this resource depends on another resource and cannot be provisioned unless the other resource has been successfully provisioned.
addMetadata(key, value)
public addMetadata(key: string, value: any): void
Parameters
- key
string
- value
any
Add a value to the CloudFormation Resource Metadata.
Note that this is a different set of metadata from CDK node metadata; this metadata ends up in the stack template under the resource, whereas CDK node metadata ends up in the Cloud Assembly.](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/metadata-section-structure.html
Note that this is a different set of metadata from CDK node metadata; this metadata ends up in the stack template under the resource, whereas CDK node metadata ends up in the Cloud Assembly.)
addOverride(path, value)
public addOverride(path: string, value: any): void
Parameters
- path
string
— - The path of the property, you can use dot notation to override values in complex types. - value
any
— - The value.
Adds an override to the synthesized CloudFormation resource.
To add a
property override, either use addPropertyOverride
or prefix path
with
"Properties." (i.e. Properties.TopicName
).
If the override is nested, separate each nested level using a dot (.) in the path parameter. If there is an array as part of the nesting, specify the index in the path.
To include a literal .
in the property name, prefix with a \
. In most
programming languages you will need to write this as "\\."
because the
\
itself will need to be escaped.
For example,
cfnResource.addOverride('Properties.GlobalSecondaryIndexes.0.Projection.NonKeyAttributes', ['myattribute']);
cfnResource.addOverride('Properties.GlobalSecondaryIndexes.1.ProjectionType', 'INCLUDE');
would add the overrides
"Properties": {
"GlobalSecondaryIndexes": [
{
"Projection": {
"NonKeyAttributes": [ "myattribute" ]
...
}
...
},
{
"ProjectionType": "INCLUDE"
...
},
]
...
}
The value
argument to addOverride
will not be processed or translated
in any way. Pass raw JSON values in here with the correct capitalization
for CloudFormation. If you pass CDK classes or structs, they will be
rendered with lowercased key names, and CloudFormation will reject the
template.
addPropertyDeletionOverride(propertyPath)
public addPropertyDeletionOverride(propertyPath: string): void
Parameters
- propertyPath
string
— The path to the property.
Adds an override that deletes the value of a property from the resource definition.
addPropertyOverride(propertyPath, value)
public addPropertyOverride(propertyPath: string, value: any): void
Parameters
- propertyPath
string
— The path of the property. - value
any
— The value.
Adds an override to a resource property.
Syntactic sugar for addOverride("Properties.<...>", value)
.
applyRemovalPolicy(policy?, options?)
public applyRemovalPolicy(policy?: RemovalPolicy, options?: RemovalPolicyOptions): void
Parameters
- policy
Removal
Policy - options
Removal
Policy Options
Sets the deletion policy of the resource based on the removal policy specified.
The Removal Policy controls what happens to this resource when it stops being managed by CloudFormation, either because you've removed it from the CDK application or because you've made a change that requires the resource to be replaced.
The resource can be deleted (RemovalPolicy.DESTROY
), or left in your AWS
account for data recovery and cleanup later (RemovalPolicy.RETAIN
). In some
cases, a snapshot can be taken of the resource prior to deletion
(RemovalPolicy.SNAPSHOT
). A list of resources that support this policy
can be found in the following link:
getAtt(attributeName, typeHint?)
public getAtt(attributeName: string, typeHint?: ResolutionTypeHint): Reference
Parameters
- attributeName
string
— The name of the attribute. - typeHint
Resolution
Type Hint
Returns
Returns a token for an runtime attribute of this resource.
Ideally, use generated attribute accessors (e.g. resource.arn
), but this can be used for future compatibility
in case there is no generated attribute.
getMetadata(key)
public getMetadata(key: string): any
Parameters
- key
string
Returns
any
Retrieve a value value from the CloudFormation Resource Metadata.
Note that this is a different set of metadata from CDK node metadata; this metadata ends up in the stack template under the resource, whereas CDK node metadata ends up in the Cloud Assembly.](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/metadata-section-structure.html
Note that this is a different set of metadata from CDK node metadata; this metadata ends up in the stack template under the resource, whereas CDK node metadata ends up in the Cloud Assembly.)
inspect(inspector)
public inspect(inspector: TreeInspector): void
Parameters
- inspector
Tree
— tree inspector to collect and process attributes.Inspector
Examines the CloudFormation resource and discloses attributes.
obtainDependencies()
public obtainDependencies(): Stack | CfnResource[]
Returns
Stack
|
Cfn
Resource []
Retrieves an array of resources this resource depends on.
This assembles dependencies on resources across stacks (including nested stacks) automatically.
obtainResourceDependencies()
public obtainResourceDependencies(): CfnResource[]
Returns
Get a shallow copy of dependencies between this resource and other resources in the same stack.
overrideLogicalId(newLogicalId)
public overrideLogicalId(newLogicalId: string): void
Parameters
- newLogicalId
string
— The new logical ID to use for this stack element.
Overrides the auto-generated logical ID with a specific ID.
removeDependency(target)
public removeDependency(target: CfnResource): void
Parameters
- target
Cfn
Resource
Indicates that this resource no longer depends on another resource.
This can be used for resources across stacks (including nested stacks) and the dependency will automatically be removed from the relevant scope.
replaceDependency(target, newTarget)
public replaceDependency(target: CfnResource, newTarget: CfnResource): void
Parameters
- target
Cfn
— The dependency to replace.Resource - newTarget
Cfn
— The new dependency to add.Resource
Replaces one dependency with another.
toString()
public toString(): string
Returns
string
Returns a string representation of this construct.
protected renderProperties(props)
protected renderProperties(props: { [string]: any }): { [string]: any }
Parameters
- props
{ [string]: any }
Returns
{ [string]: any }