AWS::CloudWatch::Alarm MetricDataQuery - AWS CloudFormation

AWS::CloudWatch::Alarm MetricDataQuery

The MetricDataQuery property type specifies the metric data to return, and whether this call is just retrieving a batch set of data for one metric, or is performing a math expression on metric data.

Any expression used must return a single time series. For more information, see Metric Math Syntax and Functions in the Amazon CloudWatch User Guide.

Syntax

To declare this entity in your AWS CloudFormation template, use the following syntax:

JSON

{ "Expression" : String, "Id" : String, "Label" : String, "MetricStat" : MetricStat, "Period" : Integer, "ReturnData" : Boolean }

YAML

Expression: String Id: String Label: String MetricStat: MetricStat Period: Integer ReturnData: Boolean

Properties

Expression

The math expression to be performed on the returned data, if this object is performing a math expression. This expression can use the Id of the other metrics to refer to those metrics, and can also use the Id of other expressions to use the result of those expressions. For more information about metric math expressions, see Metric Math Syntax and Functions in the Amazon CloudWatch User Guide.

Within each MetricDataQuery object, you must specify either Expression or MetricStat but not both.

Required: No

Type: String

Minimum: 1

Maximum: 1024

Update requires: No interruption

Id

A short name used to tie this object to the results in the response. This name must be unique within a single call to GetMetricData. If you are performing math expressions on this set of data, this name represents that data and can serve as a variable in the mathematical expression. The valid characters are letters, numbers, and underscore. The first character must be a lowercase letter.

Required: Yes

Type: String

Minimum: 1

Maximum: 255

Update requires: No interruption

Label

A human-readable label for this metric or expression. This is especially useful if this is an expression, so that you know what the value represents. If the metric or expression is shown in a CloudWatch dashboard widget, the label is shown. If Label is omitted, CloudWatch generates a default.

Required: No

Type: String

Update requires: No interruption

MetricStat

The metric to be returned, along with statistics, period, and units. Use this parameter only if this object is retrieving a metric and not performing a math expression on returned data.

Within one MetricDataQuery object, you must specify either Expression or MetricStat but not both.

Required: No

Type: MetricStat

Update requires: No interruption

Period

Not currently supported by AWS CloudFormation.

Required: No

Type: Integer

Minimum: 1

Update requires: No interruption

ReturnData

This option indicates whether to return the timestamps and raw data values of this metric.

When you create an alarm based on a metric math expression, specify True for this value for only the one math expression that the alarm is based on. You must specify False for ReturnData for all the other metrics and expressions used in the alarm.

If you omit this field, the default of True is used.

Required: No

Type: Boolean

Update requires: No interruption