getMetricStatistics method
Gets statistics for the specified metric.
The maximum number of data points returned from a single call is 1,440. If you request more than 1,440 data points, CloudWatch returns an error. To reduce the number of data points, you can narrow the specified time range and make multiple requests across adjacent time ranges, or you can increase the specified period. Data points are not returned in chronological order.
CloudWatch aggregates data points based on the length of the period that you specify. For example, if you request statistics with a one-hour period, CloudWatch aggregates all data points with time stamps that fall within each one-hour period. Therefore, the number of values aggregated by CloudWatch is larger than the number of data points returned.
CloudWatch needs raw data points to calculate percentile statistics. If you publish data using a statistic set instead, you can only retrieve percentile statistics for this data if one of the following conditions is true:
- The SampleCount value of the statistic set is 1.
- The Min and the Max values of the statistic set are equal.
Amazon CloudWatch retains metric data as follows:
-
Data points with a period of less than 60 seconds are available for 3
hours. These data points are high-resolution metrics and are available
only for custom metrics that have been defined with a
StorageResolutionof 1. - Data points with a period of 60 seconds (1-minute) are available for 15 days.
- Data points with a period of 300 seconds (5-minute) are available for 63 days.
- Data points with a period of 3600 seconds (1 hour) are available for 455 days (15 months).
CloudWatch started retaining 5-minute and 1-hour metric data as of July 9, 2016.
For information about metrics and dimensions supported by AWS services, see the Amazon CloudWatch Metrics and Dimensions Reference in the Amazon CloudWatch User Guide.
May throw InvalidParameterValueException. May throw MissingRequiredParameterException. May throw InvalidParameterCombinationException. May throw InternalServiceFault.
Parameter endTime :
The time stamp that determines the last data point to return.
The value specified is exclusive; results include data points up to the specified time stamp. In a raw HTTP query, the time stamp must be in ISO 8601 UTC format (for example, 2016-10-10T23:00:00Z).
Parameter metricName :
The name of the metric, with or without spaces.
Parameter namespace :
The namespace of the metric, with or without spaces.
Parameter period :
The granularity, in seconds, of the returned data points. For metrics with
regular resolution, a period can be as short as one minute (60 seconds)
and must be a multiple of 60. For high-resolution metrics that are
collected at intervals of less than one minute, the period can be 1, 5,
10, 30, 60, or any multiple of 60. High-resolution metrics are those
metrics stored by a PutMetricData call that includes a
StorageResolution of 1 second.
If the StartTime parameter specifies a time stamp that is
greater than 3 hours ago, you must specify the period as follows or no
data points in that time range is returned:
- Start time between 3 hours and 15 days ago - Use a multiple of 60 seconds (1 minute).
- Start time between 15 and 63 days ago - Use a multiple of 300 seconds (5 minutes).
- Start time greater than 63 days ago - Use a multiple of 3600 seconds (1 hour).
Parameter startTime :
The time stamp that determines the first data point to return. Start times
are evaluated relative to the time that CloudWatch receives the request.
The value specified is inclusive; results include data points with the specified time stamp. In a raw HTTP query, the time stamp must be in ISO 8601 UTC format (for example, 2016-10-03T23:00:00Z).
CloudWatch rounds the specified time stamp as follows:
- Start time less than 15 days ago - Round down to the nearest whole minute. For example, 12:32:34 is rounded down to 12:32:00.
- Start time between 15 and 63 days ago - Round down to the nearest 5-minute clock interval. For example, 12:32:34 is rounded down to 12:30:00.
- Start time greater than 63 days ago - Round down to the nearest 1-hour clock interval. For example, 12:32:34 is rounded down to 12:00:00.
Period to 5, 10, or 30, the start time of your
request is rounded down to the nearest time that corresponds to even 5-,
10-, or 30-second divisions of a minute. For example, if you make a query
at (HH:mm:ss) 01:05:23 for the previous 10-second period, the start time
of your request is rounded down and you receive data from 01:05:10 to
01:05:20. If you make a query at 15:07:17 for the previous 5 minutes of
data, using a period of 5 seconds, you receive data timestamped between
15:02:15 and 15:07:15.
Parameter dimensions :
The dimensions. If the metric contains multiple dimensions, you must
include a value for each dimension. CloudWatch treats each unique
combination of dimensions as a separate metric. If a specific combination
of dimensions was not published, you can't retrieve statistics for it. You
must specify the same dimensions that were used when the metrics were
created. For an example, see Dimension
Combinations in the Amazon CloudWatch User Guide. For more
information about specifying dimensions, see Publishing
Metrics in the Amazon CloudWatch User Guide.
Parameter extendedStatistics :
The percentile statistics. Specify values between p0.0 and p100. When
calling GetMetricStatistics, you must specify either
Statistics or ExtendedStatistics, but not both.
Percentile statistics are not available for metrics when any of the metric
values are negative numbers.
Parameter statistics :
The metric statistics, other than percentile. For percentile statistics,
use ExtendedStatistics. When calling
GetMetricStatistics, you must specify either
Statistics or ExtendedStatistics, but not both.
Parameter unit :
The unit for a given metric. If you omit Unit, all data that
was collected with any unit is returned, along with the corresponding
units that were specified when the data was reported to CloudWatch. If you
specify a unit, the operation returns only data that was collected with
that unit specified. If you specify a unit that does not match the data
collected, the results of the operation are null. CloudWatch does not
perform unit conversions.
Implementation
Future<GetMetricStatisticsOutput> getMetricStatistics({
required DateTime endTime,
required String metricName,
required String namespace,
required int period,
required DateTime startTime,
List<Dimension>? dimensions,
List<String>? extendedStatistics,
List<Statistic>? statistics,
StandardUnit? unit,
}) async {
ArgumentError.checkNotNull(endTime, 'endTime');
ArgumentError.checkNotNull(metricName, 'metricName');
_s.validateStringLength(
'metricName',
metricName,
1,
255,
isRequired: true,
);
ArgumentError.checkNotNull(namespace, 'namespace');
_s.validateStringLength(
'namespace',
namespace,
1,
255,
isRequired: true,
);
ArgumentError.checkNotNull(period, 'period');
_s.validateNumRange(
'period',
period,
1,
1152921504606846976,
isRequired: true,
);
ArgumentError.checkNotNull(startTime, 'startTime');
final $request = <String, dynamic>{};
$request['EndTime'] = _s.iso8601ToJson(endTime);
$request['MetricName'] = metricName;
$request['Namespace'] = namespace;
$request['Period'] = period;
$request['StartTime'] = _s.iso8601ToJson(startTime);
dimensions?.also((arg) => $request['Dimensions'] = arg);
extendedStatistics?.also((arg) => $request['ExtendedStatistics'] = arg);
statistics?.also(
(arg) => $request['Statistics'] = arg.map((e) => e.toValue()).toList());
unit?.also((arg) => $request['Unit'] = arg.toValue());
final $result = await _protocol.send(
$request,
action: 'GetMetricStatistics',
version: '2010-08-01',
method: 'POST',
requestUri: '/',
exceptionFnMap: _exceptionFns,
shape: shapes['GetMetricStatisticsInput'],
shapes: shapes,
resultWrapper: 'GetMetricStatisticsResult',
);
return GetMetricStatisticsOutput.fromXml($result);
}