Describe CloudWatch alarms for a metric using an Amazon SDK - Amazon CloudWatch
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Describe CloudWatch alarms for a metric using an Amazon SDK

The following code examples show how to describe Amazon CloudWatch alarms for a metric.

Action examples are code excerpts from larger programs and must be run in context. You can see this action in context in the following code examples:

.NET
Amazon SDK for .NET
Note

There's more on GitHub. Find the complete example and learn how to set up and run in the Amazon Code Examples Repository.

/// <summary> /// Describe the current alarms for a specific metric. /// </summary> /// <param name="metricNamespace">The namespace of the metric.</param> /// <param name="metricName">The name of the metric.</param> /// <returns>The list of alarm data.</returns> public async Task<List<MetricAlarm>> DescribeAlarmsForMetric(string metricNamespace, string metricName) { var alarmsResult = await _amazonCloudWatch.DescribeAlarmsForMetricAsync( new DescribeAlarmsForMetricRequest() { Namespace = metricNamespace, MetricName = metricName }); return alarmsResult.MetricAlarms; }
C++
SDK for C++
Note

There's more on GitHub. Find the complete example and learn how to set up and run in the Amazon Code Examples Repository.

Include the required files.

#include <aws/core/Aws.h> #include <aws/monitoring/CloudWatchClient.h> #include <aws/monitoring/model/DescribeAlarmsRequest.h> #include <aws/monitoring/model/DescribeAlarmsResult.h> #include <iomanip> #include <iostream>

Describe the alarms.

Aws::CloudWatch::CloudWatchClient cw; Aws::CloudWatch::Model::DescribeAlarmsRequest request; request.SetMaxRecords(1); bool done = false; bool header = false; while (!done) { auto outcome = cw.DescribeAlarms(request); if (!outcome.IsSuccess()) { std::cout << "Failed to describe CloudWatch alarms:" << outcome.GetError().GetMessage() << std::endl; break; } if (!header) { std::cout << std::left << std::setw(32) << "Name" << std::setw(64) << "Arn" << std::setw(64) << "Description" << std::setw(20) << "LastUpdated" << std::endl; header = true; } const auto &alarms = outcome.GetResult().GetMetricAlarms(); for (const auto &alarm : alarms) { std::cout << std::left << std::setw(32) << alarm.GetAlarmName() << std::setw(64) << alarm.GetAlarmArn() << std::setw(64) << alarm.GetAlarmDescription() << std::setw(20) << alarm.GetAlarmConfigurationUpdatedTimestamp().ToGmtString( SIMPLE_DATE_FORMAT_STR) << std::endl; } const auto &next_token = outcome.GetResult().GetNextToken(); request.SetNextToken(next_token); done = next_token.empty(); }
Java
SDK for Java 2.x
Note

There's more on GitHub. Find the complete example and learn how to set up and run in the Amazon Code Examples Repository.

public static void checkForMetricAlarm(CloudWatchClient cw, String fileName) { try { // Read values from the JSON file. JsonParser parser = new JsonFactory().createParser(new File(fileName)); com.fasterxml.jackson.databind.JsonNode rootNode = new ObjectMapper().readTree(parser); String customMetricNamespace = rootNode.findValue("customMetricNamespace").asText(); String customMetricName = rootNode.findValue("customMetricName").asText(); boolean hasAlarm = false; int retries = 10; DescribeAlarmsForMetricRequest metricRequest = DescribeAlarmsForMetricRequest.builder() .metricName(customMetricName) .namespace(customMetricNamespace) .build(); while (!hasAlarm && retries > 0) { DescribeAlarmsForMetricResponse response = cw.describeAlarmsForMetric(metricRequest); hasAlarm = response.hasMetricAlarms(); retries--; Thread.sleep(20000); System.out.println("."); } if (!hasAlarm) System.out.println("No Alarm state found for "+ customMetricName +" after 10 retries."); else System.out.println("Alarm state found for "+ customMetricName +"."); } catch (CloudWatchException | IOException | InterruptedException e) { System.err.println(e.getMessage()); System.exit(1); } }
JavaScript
SDK for JavaScript (v3)
Note

There's more on GitHub. Find the complete example and learn how to set up and run in the Amazon Code Examples Repository.

Create the client in a separate module and export it.

import { CloudWatchClient } from "@aws-sdk/client-cloudwatch"; import { DEFAULT_REGION } from "libs/utils/util-aws-sdk.js"; export const client = new CloudWatchClient({ region: DEFAULT_REGION });

Import the SDK and client modules and call the API.

import { DescribeAlarmsCommand } from "@aws-sdk/client-cloudwatch"; import { client } from "../libs/client.js"; const run = async () => { const command = new DescribeAlarmsCommand({ AlarmNames: [process.env.CLOUDWATCH_ALARM_NAME], // Set the value of CLOUDWATCH_ALARM_NAME to the name of an existing alarm. }); try { return await client.send(command); } catch (err) { console.error(err); } }; export default run();
SDK for JavaScript (v2)
Note

There's more on GitHub. Find the complete example and learn how to set up and run in the Amazon Code Examples Repository.

// Load the AWS SDK for Node.js var AWS = require('aws-sdk'); // Set the region AWS.config.update({region: 'REGION'}); // Create CloudWatch service object var cw = new AWS.CloudWatch({apiVersion: '2010-08-01'}); cw.describeAlarms({StateValue: 'INSUFFICIENT_DATA'}, function(err, data) { if (err) { console.log("Error", err); } else { // List the names of all current alarms in the console data.MetricAlarms.forEach(function (item, index, array) { console.log(item.AlarmName); }); } });
Kotlin
SDK for Kotlin
Note

This is prerelease documentation for a feature in preview release. It is subject to change.

Note

There's more on GitHub. Find the complete example and learn how to set up and run in the Amazon Code Examples Repository.

suspend fun checkForMetricAlarm(fileName: String?) { // Read values from the JSON file. val parser = JsonFactory().createParser(File(fileName)) val rootNode = ObjectMapper().readTree<JsonNode>(parser) val customMetricNamespace = rootNode.findValue("customMetricNamespace").asText() val customMetricName = rootNode.findValue("customMetricName").asText() var hasAlarm = false var retries = 10 val metricRequest = DescribeAlarmsForMetricRequest { metricName = customMetricName namespace = customMetricNamespace } CloudWatchClient { region = "us-east-1" }.use { cwClient -> while (!hasAlarm && retries > 0) { val response = cwClient.describeAlarmsForMetric(metricRequest) if (response.metricAlarms?.count()!! > 0) { hasAlarm = true } retries-- delay(20000) println(".") } if (!hasAlarm) println("No Alarm state found for $customMetricName after 10 retries.") else println("Alarm state found for $customMetricName.") } }
Python
SDK for Python (Boto3)
Note

There's more on GitHub. Find the complete example and learn how to set up and run in the Amazon Code Examples Repository.

class CloudWatchWrapper: """Encapsulates Amazon CloudWatch functions.""" def __init__(self, cloudwatch_resource): """ :param cloudwatch_resource: A Boto3 CloudWatch resource. """ self.cloudwatch_resource = cloudwatch_resource def get_metric_alarms(self, metric_namespace, metric_name): """ Gets the alarms that are currently watching the specified metric. :param metric_namespace: The namespace of the metric. :param metric_name: The name of the metric. :returns: An iterator that yields the alarms. """ metric = self.cloudwatch_resource.Metric(metric_namespace, metric_name) alarm_iter = metric.alarms.all() logger.info("Got alarms for metric %s.%s.", metric_namespace, metric_name) return alarm_iter
Ruby
SDK for Ruby
Note

There's more on GitHub. Find the complete example and learn how to set up and run in the Amazon Code Examples Repository.

require "aws-sdk-cloudwatch" # Lists the names of available Amazon CloudWatch alarms. # # @param cloudwatch_client [Aws::CloudWatch::Client] # An initialized CloudWatch client. # @example # list_alarms(Aws::CloudWatch::Client.new(region: 'us-east-1')) def list_alarms(cloudwatch_client) response = cloudwatch_client.describe_alarms if response.metric_alarms.count.positive? response.metric_alarms.each do |alarm| puts alarm.alarm_name end else puts "No alarms found." end rescue StandardError => e puts "Error getting information about alarms: #{e.message}" end

For a complete list of Amazon SDK developer guides and code examples, see Using CloudWatch with an Amazon SDK. This topic also includes information about getting started and details about previous SDK versions.