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Class: Aws::CloudWatch::Client
- Inherits:
-
Seahorse::Client::Base
- Object
- Seahorse::Client::Base
- Aws::CloudWatch::Client
- Defined in:
- (unknown)
Overview
An API client for Amazon CloudWatch. To construct a client, you need to configure a :region
and :credentials
.
cloudwatch = Aws::CloudWatch::Client.new(
region: region_name,
credentials: credentials,
# ...
)
See #initialize for a full list of supported configuration options.
Region
You can configure a default region in the following locations:
ENV['AWS_REGION']
Aws.config[:region]
Go here for a list of supported regions.
Credentials
Default credentials are loaded automatically from the following locations:
ENV['AWS_ACCESS_KEY_ID']
andENV['AWS_SECRET_ACCESS_KEY']
Aws.config[:credentials]
- The shared credentials ini file at
~/.aws/credentials
(more information) - From an instance profile when running on EC2
You can also construct a credentials object from one of the following classes:
Alternatively, you configure credentials with :access_key_id
and
:secret_access_key
:
# load credentials from disk
creds = YAML.load(File.read('/path/to/secrets'))
Aws::CloudWatch::Client.new(
access_key_id: creds['access_key_id'],
secret_access_key: creds['secret_access_key']
)
Always load your credentials from outside your application. Avoid configuring credentials statically and never commit them to source control.
Instance Attribute Summary
Attributes inherited from Seahorse::Client::Base
Constructor collapse
-
#initialize(options = {}) ⇒ Aws::CloudWatch::Client
constructor
Constructs an API client.
API Operations collapse
-
#delete_alarms(options = {}) ⇒ Struct
Deletes the specified alarms.
-
#delete_anomaly_detector(options = {}) ⇒ Struct
Deletes the specified anomaly detection model from your account.
.
-
#delete_dashboards(options = {}) ⇒ Struct
Deletes all dashboards that you specify.
-
#delete_insight_rules(options = {}) ⇒ Types::DeleteInsightRulesOutput
Permanently deletes the specified Contributor Insights rules.
If you create a rule, delete it, and then re-create it with the same name, historical data from the first time the rule was created might not be available.
. -
#describe_alarm_history(options = {}) ⇒ Types::DescribeAlarmHistoryOutput
Retrieves the history for the specified alarm.
-
#describe_alarms(options = {}) ⇒ Types::DescribeAlarmsOutput
Retrieves the specified alarms.
-
#describe_alarms_for_metric(options = {}) ⇒ Types::DescribeAlarmsForMetricOutput
Retrieves the alarms for the specified metric.
-
#describe_anomaly_detectors(options = {}) ⇒ Types::DescribeAnomalyDetectorsOutput
Lists the anomaly detection models that you have created in your account.
-
#describe_insight_rules(options = {}) ⇒ Types::DescribeInsightRulesOutput
Returns a list of all the Contributor Insights rules in your account.
For more information about Contributor Insights, see Using Contributor Insights to Analyze High-Cardinality Data.
. -
#disable_alarm_actions(options = {}) ⇒ Struct
Disables the actions for the specified alarms.
-
#disable_insight_rules(options = {}) ⇒ Types::DisableInsightRulesOutput
Disables the specified Contributor Insights rules.
-
#enable_alarm_actions(options = {}) ⇒ Struct
Enables the actions for the specified alarms.
.
-
#enable_insight_rules(options = {}) ⇒ Types::EnableInsightRulesOutput
Enables the specified Contributor Insights rules.
-
#get_dashboard(options = {}) ⇒ Types::GetDashboardOutput
Displays the details of the dashboard that you specify.
To copy an existing dashboard, use
.GetDashboard
, and then use the data returned withinDashboardBody
as the template for the new dashboard when you callPutDashboard
to create the copy. -
#get_insight_rule_report(options = {}) ⇒ Types::GetInsightRuleReportOutput
This operation returns the time series data collected by a Contributor Insights rule.
-
#get_metric_data(options = {}) ⇒ Types::GetMetricDataOutput
You can use the
GetMetricData
API to retrieve as many as 500 different metrics in a single request, with a total of as many as 100,800 data points. -
#get_metric_statistics(options = {}) ⇒ Types::GetMetricStatisticsOutput
Gets statistics for the specified metric.
The maximum number of data points returned from a single call is 1,440.
-
#get_metric_widget_image(options = {}) ⇒ Types::GetMetricWidgetImageOutput
You can use the
GetMetricWidgetImage
API to retrieve a snapshot graph of one or more Amazon CloudWatch metrics as a bitmap image. -
#list_dashboards(options = {}) ⇒ Types::ListDashboardsOutput
Returns a list of the dashboards for your account.
-
#list_metrics(options = {}) ⇒ Types::ListMetricsOutput
List the specified metrics.
-
#list_tags_for_resource(options = {}) ⇒ Types::ListTagsForResourceOutput
Displays the tags associated with a CloudWatch resource.
-
#put_anomaly_detector(options = {}) ⇒ Struct
Creates an anomaly detection model for a CloudWatch metric.
-
#put_composite_alarm(options = {}) ⇒ Struct
Creates or updates a composite alarm.
-
#put_dashboard(options = {}) ⇒ Types::PutDashboardOutput
Creates a dashboard if it does not already exist, or updates an existing dashboard.
-
#put_insight_rule(options = {}) ⇒ Struct
Creates a Contributor Insights rule.
-
#put_metric_alarm(options = {}) ⇒ Struct
Creates or updates an alarm and associates it with the specified metric, metric math expression, or anomaly detection model.
Alarms based on anomaly detection models cannot have Auto Scaling actions.
When this operation creates an alarm, the alarm state is immediately set to
INSUFFICIENT_DATA
. -
#put_metric_data(options = {}) ⇒ Struct
Publishes metric data points to Amazon CloudWatch.
-
#set_alarm_state(options = {}) ⇒ Struct
Temporarily sets the state of an alarm for testing purposes.
-
#tag_resource(options = {}) ⇒ Struct
Assigns one or more tags (key-value pairs) to the specified CloudWatch resource.
-
#untag_resource(options = {}) ⇒ Struct
Removes one or more tags from the specified resource.
.
Instance Method Summary collapse
-
#wait_until(waiter_name, params = {}) {|waiter| ... } ⇒ Boolean
Waiters polls an API operation until a resource enters a desired state.
-
#waiter_names ⇒ Array<Symbol>
Returns the list of supported waiters.
Methods inherited from Seahorse::Client::Base
add_plugin, api, #build_request, clear_plugins, define, new, #operation, #operation_names, plugins, remove_plugin, set_api, set_plugins
Methods included from Seahorse::Client::HandlerBuilder
#handle, #handle_request, #handle_response
Constructor Details
#initialize(options = {}) ⇒ Aws::CloudWatch::Client
Constructs an API client.
Instance Method Details
#delete_alarms(options = {}) ⇒ Struct
Deletes the specified alarms. You can delete up to 100 alarms in one operation. However, this total can include no more than one composite alarm. For example, you could delete 99 metric alarms and one composite alarms with one operation, but you can't delete two composite alarms with one operation.
In the event of an error, no alarms are deleted.
It is possible to create a loop or cycle of composite alarms, where composite alarm A depends on composite alarm B, and composite alarm B also depends on composite alarm A. In this scenario, you can't delete any composite alarm that is part of the cycle because there is always still a composite alarm that depends on that alarm that you want to delete.
To get out of such a situation, you must break the cycle by changing the rule of one of the composite alarms in the cycle to remove a dependency that creates the cycle. The simplest change to make to break a cycle is to change the AlarmRule
of one of the alarms to False
.
Additionally, the evaluation of composite alarms stops if CloudWatch detects a cycle in the evaluation path.
#delete_anomaly_detector(options = {}) ⇒ Struct
Deletes the specified anomaly detection model from your account.
#delete_dashboards(options = {}) ⇒ Struct
Deletes all dashboards that you specify. You can specify up to 100 dashboards to delete. If there is an error during this call, no dashboards are deleted.
#delete_insight_rules(options = {}) ⇒ Types::DeleteInsightRulesOutput
Permanently deletes the specified Contributor Insights rules.
If you create a rule, delete it, and then re-create it with the same name, historical data from the first time the rule was created might not be available.
#describe_alarm_history(options = {}) ⇒ Types::DescribeAlarmHistoryOutput
Retrieves the history for the specified alarm. You can filter the results by date range or item type. If an alarm name is not specified, the histories for either all metric alarms or all composite alarms are returned.
CloudWatch retains the history of an alarm even if you delete the alarm.
#describe_alarms(options = {}) ⇒ Types::DescribeAlarmsOutput
Retrieves the specified alarms. You can filter the results by specifying a a prefix for the alarm name, the alarm state, or a prefix for any action.
#describe_alarms_for_metric(options = {}) ⇒ Types::DescribeAlarmsForMetricOutput
Retrieves the alarms for the specified metric. To filter the results, specify a statistic, period, or unit.
This operation retrieves only standard alarms that are based on the specified metric. It does not return alarms based on math expressions that use the specified metric, or composite alarms that use the specified metric.
#describe_anomaly_detectors(options = {}) ⇒ Types::DescribeAnomalyDetectorsOutput
Lists the anomaly detection models that you have created in your account. You can list all models in your account or filter the results to only the models that are related to a certain namespace, metric name, or metric dimension.
#describe_insight_rules(options = {}) ⇒ Types::DescribeInsightRulesOutput
Returns a list of all the Contributor Insights rules in your account.
For more information about Contributor Insights, see Using Contributor Insights to Analyze High-Cardinality Data.
#disable_alarm_actions(options = {}) ⇒ Struct
Disables the actions for the specified alarms. When an alarm's actions are disabled, the alarm actions do not execute when the alarm state changes.
#disable_insight_rules(options = {}) ⇒ Types::DisableInsightRulesOutput
Disables the specified Contributor Insights rules. When rules are disabled, they do not analyze log groups and do not incur costs.
#enable_alarm_actions(options = {}) ⇒ Struct
Enables the actions for the specified alarms.
#enable_insight_rules(options = {}) ⇒ Types::EnableInsightRulesOutput
Enables the specified Contributor Insights rules. When rules are enabled, they immediately begin analyzing log data.
#get_dashboard(options = {}) ⇒ Types::GetDashboardOutput
Displays the details of the dashboard that you specify.
To copy an existing dashboard, use GetDashboard
, and then use the data returned within DashboardBody
as the template for the new dashboard when you call PutDashboard
to create the copy.
#get_insight_rule_report(options = {}) ⇒ Types::GetInsightRuleReportOutput
This operation returns the time series data collected by a Contributor Insights rule. The data includes the identity and number of contributors to the log group.
You can also optionally return one or more statistics about each data point in the time series. These statistics can include the following:
-
UniqueContributors
-- the number of unique contributors for each data point. -
MaxContributorValue
-- the value of the top contributor for each data point. The identity of the contributor might change for each data point in the graph.If this rule aggregates by COUNT, the top contributor for each data point is the contributor with the most occurrences in that period. If the rule aggregates by SUM, the top contributor is the contributor with the highest sum in the log field specified by the rule's
Value
, during that period. -
SampleCount
-- the number of data points matched by the rule. -
Sum
-- the sum of the values from all contributors during the time period represented by that data point. -
Minimum
-- the minimum value from a single observation during the time period represented by that data point. -
Maximum
-- the maximum value from a single observation during the time period represented by that data point. -
Average
-- the average value from all contributors during the time period represented by that data point.
#get_metric_data(options = {}) ⇒ Types::GetMetricDataOutput
You can use the GetMetricData
API to retrieve as many as 500 different metrics in a single request, with a total of as many as 100,800 data points. You can also optionally perform math expressions on the values of the returned statistics, to create new time series that represent new insights into your data. For example, using Lambda metrics, you could divide the Errors metric by the Invocations metric to get an error rate time series. For more information about metric math expressions, see Metric Math Syntax and Functions in the Amazon CloudWatch User Guide.
Calls to the GetMetricData
API have a different pricing structure than calls to GetMetricStatistics
. For more information about pricing, see Amazon CloudWatch Pricing.
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
StorageResolution
of 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).
Data points that are initially published with a shorter period are aggregated together for long-term storage. For example, if you collect data using a period of 1 minute, the data remains available for 15 days with 1-minute resolution. After 15 days, this data is still available, but is aggregated and retrievable only with a resolution of 5 minutes. After 63 days, the data is further aggregated and is available with a resolution of 1 hour.
If you omit Unit
in your request, 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.
#get_metric_statistics(options = {}) ⇒ Types::GetMetricStatisticsOutput
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.
Percentile statistics are not available for metrics when any of the metric values are negative numbers.
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
StorageResolution
of 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).
Data points that are initially published with a shorter period are aggregated together for long-term storage. For example, if you collect data using a period of 1 minute, the data remains available for 15 days with 1-minute resolution. After 15 days, this data is still available, but is aggregated and retrievable only with a resolution of 5 minutes. After 63 days, the data is further aggregated and is available with a resolution of 1 hour.
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.
#get_metric_widget_image(options = {}) ⇒ Types::GetMetricWidgetImageOutput
You can use the GetMetricWidgetImage
API to retrieve a snapshot graph of one or more Amazon CloudWatch metrics as a bitmap image. You can then embed this image into your services and products, such as wiki pages, reports, and documents. You could also retrieve images regularly, such as every minute, and create your own custom live dashboard.
The graph you retrieve can include all CloudWatch metric graph features, including metric math and horizontal and vertical annotations.
There is a limit of 20 transactions per second for this API. Each GetMetricWidgetImage
action has the following limits:
-
As many as 100 metrics in the graph.
-
Up to 100 KB uncompressed payload.
#list_dashboards(options = {}) ⇒ Types::ListDashboardsOutput
Returns a list of the dashboards for your account. If you include DashboardNamePrefix
, only those dashboards with names starting with the prefix are listed. Otherwise, all dashboards in your account are listed.
ListDashboards
returns up to 1000 results on one page. If there are more than 1000 dashboards, you can call ListDashboards
again and include the value you received for NextToken
in the first call, to receive the next 1000 results.
#list_metrics(options = {}) ⇒ Types::ListMetricsOutput
List the specified metrics. You can use the returned metrics with GetMetricData or GetMetricStatistics to obtain statistical data.
Up to 500 results are returned for any one call. To retrieve additional results, use the returned token with subsequent calls.
After you create a metric, allow up to 15 minutes before the metric appears. You can see statistics about the metric sooner by using GetMetricData or GetMetricStatistics.
ListMetrics
doesn't return information about metrics if those metrics haven't reported data in the past two weeks. To retrieve those metrics, use GetMetricData or GetMetricStatistics.
#list_tags_for_resource(options = {}) ⇒ Types::ListTagsForResourceOutput
Displays the tags associated with a CloudWatch resource. Currently, alarms and Contributor Insights rules support tagging.
#put_anomaly_detector(options = {}) ⇒ Struct
Creates an anomaly detection model for a CloudWatch metric. You can use the model to display a band of expected normal values when the metric is graphed.
For more information, see CloudWatch Anomaly Detection.
#put_composite_alarm(options = {}) ⇒ Struct
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.
Currently, the only alarm actions that can be taken by composite alarms are notifying SNS topics.
It is possible to create a loop or cycle of composite alarms, where composite alarm A depends on composite alarm B, and composite alarm B also depends on composite alarm A. In this scenario, you can't delete any composite alarm that is part of the cycle because there is always still a composite alarm that depends on that alarm that you want to delete.
To get out of such a situation, you must break the cycle by changing the rule of one of the composite alarms in the cycle to remove a dependency that creates the cycle. The simplest change to make to break a cycle is to change the AlarmRule
of one of the alarms to False
.
Additionally, the evaluation of composite alarms stops if CloudWatch detects a cycle in the evaluation path.
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.
#put_dashboard(options = {}) ⇒ Types::PutDashboardOutput
Creates a dashboard if it does not already exist, or updates an existing dashboard. If you update a dashboard, the entire contents are replaced with what you specify here.
All dashboards in your account are global, not region-specific.
A simple way to create a dashboard using PutDashboard
is to copy an existing dashboard. To copy an existing dashboard using the console, you can load the dashboard and then use the View/edit source command in the Actions menu to display the JSON block for that dashboard. Another way to copy a dashboard is to use GetDashboard
, and then use the data returned within DashboardBody
as the template for the new dashboard when you call PutDashboard
.
When you create a dashboard with PutDashboard
, a good practice is to add a text widget at the top of the dashboard with a message that the dashboard was created by script and should not be changed in the console. This message could also point console users to the location of the DashboardBody
script or the CloudFormation template used to create the dashboard.
#put_insight_rule(options = {}) ⇒ Struct
Creates 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.
If you create a rule, delete it, and then re-create it with the same name, historical data from the first time the rule was created might not be available.
#put_metric_alarm(options = {}) ⇒ Struct
Creates or updates an alarm and associates it with the specified metric, metric math expression, or anomaly detection model.
Alarms based on anomaly detection models cannot have Auto Scaling actions.
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.
If you are an IAM user, you must have Amazon EC2 permissions for some alarm operations:
-
iam:CreateServiceLinkedRole
for all alarms with EC2 actions -
ec2:DescribeInstanceStatus
andec2:DescribeInstances
for all alarms on EC2 instance status metrics -
ec2:StopInstances
for alarms with stop actions -
ec2:TerminateInstances
for alarms with terminate actions -
No specific permissions are needed for alarms with recover actions
If you have read/write permissions for Amazon CloudWatch but not for Amazon EC2, you can still create an alarm, but the stop or terminate actions are not performed. However, if you are later granted the required permissions, the alarm actions that you created earlier are performed.
If you are using an IAM role (for example, an EC2 instance profile), you cannot stop or terminate the instance using alarm actions. However, you can still see the alarm state and perform any other actions such as Amazon SNS notifications or Auto Scaling policies.
If you are using temporary security credentials granted using AWS STS, you cannot stop or terminate an EC2 instance using alarm actions.
The first time you create an alarm in the AWS Management Console, the CLI, or by using the PutMetricAlarm API, CloudWatch creates the necessary service-linked role for you. The service-linked role is called AWSServiceRoleForCloudWatchEvents
. For more information, see AWS service-linked role.
#put_metric_data(options = {}) ⇒ Struct
Publishes metric data points to Amazon CloudWatch. CloudWatch associates the data points with the specified metric. If the specified metric does not exist, CloudWatch creates the metric. When CloudWatch creates a metric, it can take up to fifteen minutes for the metric to appear in calls to ListMetrics.
You can publish either individual data points in the Value
field, or arrays of values and the number of times each value occurred during the period by using the Values
and Counts
fields in the MetricDatum
structure. Using the Values
and Counts
method enables you to publish up to 150 values per metric with one PutMetricData
request, and supports retrieving percentile statistics on this data.
Each PutMetricData
request is limited to 40 KB in size for HTTP POST requests. You can send a payload compressed by gzip. Each request is also limited to no more than 20 different metrics.
Although the Value
parameter accepts numbers of type Double
, CloudWatch rejects values that are either too small or too large. Values must be in the range of -2360 to 2360. In addition, special values (for example, NaN, +Infinity, -Infinity) are not supported.
You can use up to 10 dimensions per metric to further clarify what data the metric collects. Each dimension consists of a Name and Value pair. For more information about specifying dimensions, see Publishing Metrics in the Amazon CloudWatch User Guide.
You specify the time stamp to be associated with each data point. You can specify time stamps that are as much as two weeks before the current date, and as much as 2 hours after the current day and time.
Data points with time stamps from 24 hours ago or longer can take at least 48 hours to become available for GetMetricData or GetMetricStatistics from the time they are submitted. Data points with time stamps between 3 and 24 hours ago can take as much as 2 hours to become available for for GetMetricData or GetMetricStatistics.
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 andMin
,Max
, andSum
are all equal. -
The
Min
andMax
are equal, andSum
is equal toMin
multiplied bySampleCount
.
#set_alarm_state(options = {}) ⇒ Struct
Temporarily sets the state of an alarm for testing purposes. When the updated state differs from the previous value, the action configured for the appropriate state is invoked. For example, if your alarm is configured to send an Amazon SNS message when an alarm is triggered, temporarily changing the alarm state to ALARM
sends an SNS message.
Metric alarms returns to their actual state quickly, often within seconds. Because the metric alarm state change happens quickly, it is typically only visible in the alarm's History tab in the Amazon CloudWatch console or through DescribeAlarmHistory.
If you use SetAlarmState
on a composite alarm, the composite alarm is not guaranteed to return to its actual state. It returns to its actual state only once any of its children alarms change state. It is also reevaluated if you update its configuration.
If an alarm triggers EC2 Auto Scaling policies or application Auto Scaling policies, you must include information in the StateReasonData
parameter to enable the policy to take the correct action.
#tag_resource(options = {}) ⇒ Struct
Assigns one or more tags (key-value pairs) to the specified CloudWatch resource. Currently, the only CloudWatch resources that can be tagged are alarms and Contributor Insights rules.
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.
Tags don't have any semantic meaning to AWS and are interpreted strictly as strings of characters.
You can use the TagResource
action with an alarm that already has tags. If you specify a new tag key for the alarm, this tag is appended to the list of tags associated with the alarm. If you specify a tag key that is already associated with the alarm, the new tag value that you specify replaces the previous value for that tag.
You can associate as many as 50 tags with a CloudWatch resource.
#untag_resource(options = {}) ⇒ Struct
Removes one or more tags from the specified resource.
#wait_until(waiter_name, params = {}) {|waiter| ... } ⇒ Boolean
Waiters polls an API operation until a resource enters a desired state.
Basic Usage
Waiters will poll until they are succesful, they fail by entering a terminal state, or until a maximum number of attempts are made.
# polls in a loop, sleeping between attempts client.waiter_until(waiter_name, params)
Configuration
You can configure the maximum number of polling attempts, and the delay (in seconds) between each polling attempt. You configure waiters by passing a block to #wait_until:
# poll for ~25 seconds
client.wait_until(...) do |w|
w.max_attempts = 5
w.delay = 5
end
Callbacks
You can be notified before each polling attempt and before each
delay. If you throw :success
or :failure
from these callbacks,
it will terminate the waiter.
started_at = Time.now
client.wait_until(...) do |w|
# disable max attempts
w.max_attempts = nil
# poll for 1 hour, instead of a number of attempts
w.before_wait do |attempts, response|
throw :failure if Time.now - started_at > 3600
end
end
Handling Errors
When a waiter is successful, it returns true
. When a waiter
fails, it raises an error. All errors raised extend from
Waiters::Errors::WaiterFailed.
begin
client.wait_until(...)
rescue Aws::Waiters::Errors::WaiterFailed
# resource did not enter the desired state in time
end
#waiter_names ⇒ Array<Symbol>
Returns the list of supported waiters. The following table lists the supported waiters and the client method they call:
Waiter Name | Client Method | Default Delay: | Default Max Attempts: |
---|---|---|---|
:alarm_exists | #describe_alarms | 5 | 40 |
:composite_alarm_exists | #describe_alarms | 5 | 40 |