Use DescribeAlarmHistory with an AWS SDK or CLI - Amazon CloudWatch

Use DescribeAlarmHistory with an AWS SDK or CLI

The following code examples show how to use DescribeAlarmHistory.

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 example:

.NET
AWS SDK for .NET
Note

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

    /// <summary>
    /// Describe the history of an alarm for a number of days in the past.
    /// </summary>
    /// <param name="alarmName">The name of the alarm.</param>
    /// <param name="historyDays">The number of days in the past.</param>
    /// <returns>The list of alarm history data.</returns>
    public async Task<List<AlarmHistoryItem>> DescribeAlarmHistory(string alarmName, int historyDays)
    {
        List<AlarmHistoryItem> alarmHistory = new List<AlarmHistoryItem>();
        var paginatedAlarmHistory = _amazonCloudWatch.Paginators.DescribeAlarmHistory(
            new DescribeAlarmHistoryRequest()
            {
                AlarmName = alarmName,
                EndDateUtc = DateTime.UtcNow,
                HistoryItemType = HistoryItemType.StateUpdate,
                StartDateUtc = DateTime.UtcNow.AddDays(-historyDays)
            });

        await foreach (var data in paginatedAlarmHistory.AlarmHistoryItems)
        {
            alarmHistory.Add(data);
        }
        return alarmHistory;
    }
CLI
AWS CLI

To retrieve history for an alarm

The following example uses the describe-alarm-history command to retrieve history for the Amazon CloudWatch alarm named "myalarm":

aws cloudwatch describe-alarm-history --alarm-name "myalarm" --history-item-type StateUpdate

Output:

{
    "AlarmHistoryItems": [
        {
            "Timestamp": "2014-04-09T18:59:06.442Z",
            "HistoryItemType": "StateUpdate",
            "AlarmName": "myalarm",
            "HistoryData": "{\"version\":\"1.0\",\"oldState\":{\"stateValue\":\"ALARM\",\"stateReason\":\"testing purposes\"},\"newState\":{\"stateValue\":\"OK\",\"stateReason\":\"Threshold Crossed: 2 datapoints were not greater than the threshold (70.0). The most recent datapoints: [38.958, 40.292].\",\"stateReasonData\":{\"version\":\"1.0\",\"queryDate\":\"2014-04-09T18:59:06.419+0000\",\"startDate\":\"2014-04-09T18:44:00.000+0000\",\"statistic\":\"Average\",\"period\":300,\"recentDatapoints\":[38.958,40.292],\"threshold\":70.0}}}",
            "HistorySummary": "Alarm updated from ALARM to OK"
        },
        {
            "Timestamp": "2014-04-09T18:59:05.805Z",
            "HistoryItemType": "StateUpdate",
            "AlarmName": "myalarm",
            "HistoryData": "{\"version\":\"1.0\",\"oldState\":{\"stateValue\":\"OK\",\"stateReason\":\"Threshold Crossed: 2 datapoints were not greater than the threshold (70.0). The most recent datapoints: [38.839999999999996, 39.714].\",\"stateReasonData\":{\"version\":\"1.0\",\"queryDate\":\"2014-03-11T22:45:41.569+0000\",\"startDate\":\"2014-03-11T22:30:00.000+0000\",\"statistic\":\"Average\",\"period\":300,\"recentDatapoints\":[38.839999999999996,39.714],\"threshold\":70.0}},\"newState\":{\"stateValue\":\"ALARM\",\"stateReason\":\"testing purposes\"}}",
            "HistorySummary": "Alarm updated from OK to ALARM"
        }
    ]
}
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 AWS Code Examples Repository. 


    /**
     * Retrieves the alarm history for a given alarm name and date range.
     *
     * @param fileName the path to the JSON file containing the alarm name
     * @param date     the date to start the alarm history search (in the format "yyyy-MM-dd'T'HH:mm:ss'Z'")
     * @return a {@code CompletableFuture<Void>} that completes when the alarm history has been retrieved and processed
     */
    public CompletableFuture<Void> getAlarmHistoryAsync(String fileName, String date) {
        CompletableFuture<String> readFileFuture = CompletableFuture.supplyAsync(() -> {
            try {
                JsonParser parser = new JsonFactory().createParser(new File(fileName));
                com.fasterxml.jackson.databind.JsonNode rootNode = new ObjectMapper().readTree(parser);
                return rootNode.findValue("exampleAlarmName").asText(); // Return alarmName from the JSON file
            } catch (IOException e) {
                throw new RuntimeException("Failed to read or parse the file", e);
            }
        });

        // Use the alarm name to describe alarm history with a paginator.
        return readFileFuture.thenCompose(alarmName -> {
            try {
                Instant start = Instant.parse(date);
                Instant endDate = Instant.now();
                DescribeAlarmHistoryRequest historyRequest = DescribeAlarmHistoryRequest.builder()
                    .startDate(start)
                    .endDate(endDate)
                    .alarmName(alarmName)
                    .historyItemType(HistoryItemType.ACTION)
                    .build();

                // Use the paginator to paginate through alarm history pages.
                DescribeAlarmHistoryPublisher historyPublisher = getAsyncClient().describeAlarmHistoryPaginator(historyRequest);
                CompletableFuture<Void> future = historyPublisher
                    .subscribe(response -> response.alarmHistoryItems().forEach(item -> {
                        logger.info("History summary: {}", item.historySummary());
                        logger.info("Timestamp: {}", item.timestamp());
                    }))
                    .whenComplete((result, exception) -> {
                        if (exception != null) {
                            logger.error("Error occurred while getting alarm history: " + exception.getMessage(), exception);
                        } else {
                            logger.info("Successfully retrieved all alarm history.");
                        }
                    });

                // Return the future to the calling code for further handling
                return future;
            } catch (Exception e) {
                throw new RuntimeException("Failed to process alarm history", e);
            }
        }).whenComplete((result, exception) -> {
            if (exception != null) {
                throw new RuntimeException("Error completing alarm history processing", exception);
            }
        });
    }
Kotlin
SDK for Kotlin
Note

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

suspend fun getAlarmHistory(
    fileName: String,
    date: String,
) {
    // Read values from the JSON file.
    val parser = JsonFactory().createParser(File(fileName))
    val rootNode = ObjectMapper().readTree<JsonNode>(parser)
    val alarmNameVal = rootNode.findValue("exampleAlarmName").asText()
    val start = Instant.parse(date)
    val endDateVal = Instant.now()

    val historyRequest =
        DescribeAlarmHistoryRequest {
            startDate =
                aws.smithy.kotlin.runtime.time
                    .Instant(start)
            endDate =
                aws.smithy.kotlin.runtime.time
                    .Instant(endDateVal)
            alarmName = alarmNameVal
            historyItemType = HistoryItemType.Action
        }

    CloudWatchClient {
        credentialsProvider = EnvironmentCredentialsProvider()
        region = "us-east-1"
    }.use { cwClient ->
        val response = cwClient.describeAlarmHistory(historyRequest)
        val historyItems = response.alarmHistoryItems
        if (historyItems != null) {
            if (historyItems.isEmpty()) {
                println("No alarm history data found for $alarmNameVal.")
            } else {
                for (item in historyItems) {
                    println("History summary ${item.historySummary}")
                    println("Time stamp: ${item.timestamp}")
                }
            }
        }
    }
}

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