Ejemplos de registros de CloudWatch usando SDK para Java 2.x - AWS SDK for Java 2.x

Ejemplos de registros de CloudWatch usando SDK para Java 2.x

En los siguientes ejemplos de código se muestra cómo realizar acciones e implementar escenarios comunes usando AWS SDK for Java 2.x con registros de CloudWatch.

Las acciones son extractos de código de programas más grandes y deben ejecutarse en contexto. Mientras las acciones muestran cómo llamar a las distintas funciones de servicio, es posible ver las acciones en contexto en los escenarios relacionados.

Los escenarios son ejemplos de código que muestran cómo llevar a cabo una tarea específica a través de llamadas a varias funciones dentro del servicio o combinado con otros Servicios de AWS.

En cada ejemplo se incluye un enlace al código de origen completo, con instrucciones de configuración y ejecución del código en el contexto.

Acciones

En el siguiente ejemplo de código, se muestra cómo utilizar DeleteSubscriptionFilter.

SDK para Java 2.x
nota

Hay más en GitHub. Busque el ejemplo completo y aprenda a configurar y ejecutar en el Repositorio de ejemplos de código de AWS.

import software.amazon.awssdk.services.cloudwatch.model.CloudWatchException; import software.amazon.awssdk.services.cloudwatchlogs.CloudWatchLogsClient; import software.amazon.awssdk.services.cloudwatchlogs.model.DeleteSubscriptionFilterRequest; /** * Before running this Java V2 code example, set up your development * environment, including your credentials. * * For more information, see the following documentation topic: * * https://docs.aws.amazon.com/sdk-for-java/latest/developer-guide/get-started.html */ public class DeleteSubscriptionFilter { public static void main(String[] args) { final String usage = """ Usage: <filter> <logGroup> Where: filter - The name of the subscription filter (for example, MyFilter). logGroup - The name of the log group. (for example, testgroup). """; if (args.length != 2) { System.out.println(usage); System.exit(1); } String filter = args[0]; String logGroup = args[1]; CloudWatchLogsClient logs = CloudWatchLogsClient.builder() .build(); deleteSubFilter(logs, filter, logGroup); logs.close(); } public static void deleteSubFilter(CloudWatchLogsClient logs, String filter, String logGroup) { try { DeleteSubscriptionFilterRequest request = DeleteSubscriptionFilterRequest.builder() .filterName(filter) .logGroupName(logGroup) .build(); logs.deleteSubscriptionFilter(request); System.out.printf("Successfully deleted CloudWatch logs subscription filter %s", filter); } catch (CloudWatchException e) { System.err.println(e.awsErrorDetails().errorMessage()); System.exit(1); } } }
  • Para obtener información sobre la API, consulte DeleteSubscriptionFilter en la Referencia de la API de AWS SDK for Java 2.x.

En el siguiente ejemplo de código, se muestra cómo utilizar DescribeLogStreams.

SDK para Java 2.x
nota

Hay más en GitHub. Busque el ejemplo completo y aprenda a configurar y ejecutar en el Repositorio de ejemplos de código de AWS.

Busca flujos de registro dentro de un grupo de registros específico que coincidan con un prefijo determinado.

/** * Before running this Java V2 code example, set up your development * environment, including your credentials. * <p> * For more information, see the following documentation topic: * <p> * https://docs.aws.amazon.com/sdk-for-java/latest/developer-guide/get-started.html */ public class CloudWatchLogsSearch { public static void main(String[] args) { final String usage = """ Usage: <logGroupName> <logStreamName> Where: logGroupName - The name of the log group (for example, WeathertopJavaContainerLogs). logStreamName - The name of the log stream (for example, weathertop-java-stream). pattern - the pattern to use (for example, INFO) """; if (args.length != 3) { System.out.print(usage); System.exit(1); } String logGroupName = args[0] ; String logStreamName = args[1] ; String pattern = args[2] ; CloudWatchLogsClient cwlClient = CloudWatchLogsClient.builder() .region(Region.US_EAST_1) .build(); searchLogStreamsAndFilterEvents(cwlClient, logGroupName, logStreamName, pattern); } /** * Searches for log streams with a specific prefix within a log group and filters log events based on a specified pattern. * * @param cwlClient the CloudWatchLogsClient used to interact with AWS CloudWatch Logs * @param logGroupName the name of the log group to search within * @param logStreamPrefix the prefix of the log streams to search for * @param pattern the pattern to filter log events by */ public static void searchLogStreamsAndFilterEvents(CloudWatchLogsClient cwlClient, String logGroupName, String logStreamPrefix, String pattern) { DescribeLogStreamsRequest describeLogStreamsRequest = DescribeLogStreamsRequest.builder() .logGroupName(logGroupName) .logStreamNamePrefix(logStreamPrefix) .build(); DescribeLogStreamsResponse describeLogStreamsResponse = cwlClient.describeLogStreams(describeLogStreamsRequest); List<LogStream> logStreams = describeLogStreamsResponse.logStreams(); for (LogStream logStream : logStreams) { String logStreamName = logStream.logStreamName(); System.out.println("Searching in log stream: " + logStreamName); FilterLogEventsRequest filterLogEventsRequest = FilterLogEventsRequest.builder() .logGroupName(logGroupName) .logStreamNames(logStreamName) .filterPattern(pattern) .build(); FilterLogEventsResponse filterLogEventsResponse = cwlClient.filterLogEvents(filterLogEventsRequest); for (FilteredLogEvent event : filterLogEventsResponse.events()) { System.out.println(event.message()); } System.out.println("--------------------------------------------------"); // Separator for better readability } } }

Imprime los metadatos sobre el flujo de registro más reciente de un grupo de registros especificado.

/** * Before running this Java V2 code example, set up your development * environment, including your credentials. * <p> * For more information, see the following documentation topic: * <p> * https://docs.aws.amazon.com/sdk-for-java/latest/developer-guide/get-started.html */ public class CloudWatchLogQuery { public static void main(final String[] args) { final String usage = """ Usage: <logGroupName> Where: logGroupName - The name of the log group (for example, /aws/lambda/ChatAIHandler). """; if (args.length != 1) { System.out.print(usage); System.exit(1); } String logGroupName = "/aws/lambda/ChatAIHandler" ; //args[0]; CloudWatchLogsClient logsClient = CloudWatchLogsClient.builder() .region(Region.US_EAST_1) .build(); describeMostRecentLogStream(logsClient, logGroupName); } /** * Describes and prints metadata about the most recent log stream in the specified log group. * * @param logsClient the CloudWatchLogsClient used to interact with AWS CloudWatch Logs * @param logGroupName the name of the log group */ public static void describeMostRecentLogStream(CloudWatchLogsClient logsClient, String logGroupName) { DescribeLogStreamsRequest streamsRequest = DescribeLogStreamsRequest.builder() .logGroupName(logGroupName) .orderBy(OrderBy.LAST_EVENT_TIME) .descending(true) .limit(1) .build(); try { DescribeLogStreamsResponse streamsResponse = logsClient.describeLogStreams(streamsRequest); List<LogStream> logStreams = streamsResponse.logStreams(); if (logStreams.isEmpty()) { System.out.println("No log streams found for log group: " + logGroupName); return; } LogStream stream = logStreams.get(0); System.out.println("Most Recent Log Stream:"); System.out.println(" Name: " + stream.logStreamName()); System.out.println(" ARN: " + stream.arn()); System.out.println(" Creation Time: " + stream.creationTime()); System.out.println(" First Event Time: " + stream.firstEventTimestamp()); System.out.println(" Last Event Time: " + stream.lastEventTimestamp()); System.out.println(" Stored Bytes: " + stream.storedBytes()); System.out.println(" Upload Sequence Token: " + stream.uploadSequenceToken()); } catch (CloudWatchLogsException e) { System.err.println("Failed to describe log stream: " + e.awsErrorDetails().errorMessage()); } } }
  • Para obtener información sobre la API, consulte DescribeLogStreams en la Referencia de la API de AWS SDK for Java 2.x.

En el siguiente ejemplo de código, se muestra cómo utilizar DescribeSubscriptionFilters.

SDK para Java 2.x
nota

Hay más en GitHub. Busque el ejemplo completo y aprenda a configurar y ejecutar en el Repositorio de ejemplos de código de AWS.

import software.amazon.awssdk.auth.credentials.ProfileCredentialsProvider; import software.amazon.awssdk.services.cloudwatch.model.CloudWatchException; import software.amazon.awssdk.services.cloudwatchlogs.CloudWatchLogsClient; import software.amazon.awssdk.services.cloudwatchlogs.model.DescribeSubscriptionFiltersRequest; import software.amazon.awssdk.services.cloudwatchlogs.model.DescribeSubscriptionFiltersResponse; import software.amazon.awssdk.services.cloudwatchlogs.model.SubscriptionFilter; /** * Before running this Java V2 code example, set up your development * environment, including your credentials. * * For more information, see the following documentation topic: * * https://docs.aws.amazon.com/sdk-for-java/latest/developer-guide/get-started.html */ public class DescribeSubscriptionFilters { public static void main(String[] args) { final String usage = """ Usage: <logGroup> Where: logGroup - A log group name (for example, myloggroup). """; if (args.length != 1) { System.out.println(usage); System.exit(1); } String logGroup = args[0]; CloudWatchLogsClient logs = CloudWatchLogsClient.builder() .credentialsProvider(ProfileCredentialsProvider.create()) .build(); describeFilters(logs, logGroup); logs.close(); } public static void describeFilters(CloudWatchLogsClient logs, String logGroup) { try { boolean done = false; String newToken = null; while (!done) { DescribeSubscriptionFiltersResponse response; if (newToken == null) { DescribeSubscriptionFiltersRequest request = DescribeSubscriptionFiltersRequest.builder() .logGroupName(logGroup) .limit(1).build(); response = logs.describeSubscriptionFilters(request); } else { DescribeSubscriptionFiltersRequest request = DescribeSubscriptionFiltersRequest.builder() .nextToken(newToken) .logGroupName(logGroup) .limit(1).build(); response = logs.describeSubscriptionFilters(request); } for (SubscriptionFilter filter : response.subscriptionFilters()) { System.out.printf("Retrieved filter with name %s, " + "pattern %s " + "and destination arn %s", filter.filterName(), filter.filterPattern(), filter.destinationArn()); } if (response.nextToken() == null) { done = true; } else { newToken = response.nextToken(); } } } catch (CloudWatchException e) { System.err.println(e.awsErrorDetails().errorMessage()); System.exit(1); } System.out.printf("Done"); } }

En el siguiente ejemplo de código, se muestra cómo utilizar GetLogEvents.

SDK para Java 2.x
nota

Hay más en GitHub. Busque el ejemplo completo y aprenda a configurar y ejecutar en el Repositorio de ejemplos de código de AWS.

import software.amazon.awssdk.regions.Region; import software.amazon.awssdk.services.cloudwatch.model.CloudWatchException; import software.amazon.awssdk.services.cloudwatchlogs.CloudWatchLogsClient; import software.amazon.awssdk.services.cloudwatchlogs.model.DescribeLogStreamsRequest; import software.amazon.awssdk.services.cloudwatchlogs.model.DescribeLogStreamsResponse; import software.amazon.awssdk.services.cloudwatchlogs.model.GetLogEventsRequest; import software.amazon.awssdk.services.cloudwatchlogs.model.GetLogEventsResponse; import java.time.Instant; import java.time.temporal.ChronoUnit; /** * Before running this Java V2 code example, set up your development * environment, including your credentials. * * For more information, see the following documentation topic: * * https://docs.aws.amazon.com/sdk-for-java/latest/developer-guide/get-started.html */ public class GetLogEvents { public static void main(String[] args) { final String usage = """ Usage: <logGroupName> <logStreamName> Where: logGroupName - The name of the log group (for example, myloggroup). logStreamName - The name of the log stream (for example, mystream). """; // if (args.length != 2) { // System.out.print(usage); // System.exit(1); // } String logGroupName = "WeathertopJavaContainerLogs" ; //args[0]; String logStreamName = "weathertop-java-stream" ; //args[1]; Region region = Region.US_EAST_1 ; CloudWatchLogsClient cloudWatchLogsClient = CloudWatchLogsClient.builder() .region(region) .build(); getCWLogEvents(cloudWatchLogsClient, logGroupName, logStreamName); cloudWatchLogsClient.close(); } public static void getCWLogEvents(CloudWatchLogsClient cloudWatchLogsClient, String logGroupName, String logStreamPrefix) { try { // First, find the exact log stream name DescribeLogStreamsRequest describeRequest = DescribeLogStreamsRequest.builder() .logGroupName(logGroupName) .logStreamNamePrefix(logStreamPrefix) .limit(1) // get the first matching stream .build(); DescribeLogStreamsResponse describeResponse = cloudWatchLogsClient.describeLogStreams(describeRequest); if (describeResponse.logStreams().isEmpty()) { System.out.println("No matching log streams found for prefix: " + logStreamPrefix); return; } String exactLogStreamName = describeResponse.logStreams().get(0).logStreamName(); System.out.println("Using exact log stream: " + exactLogStreamName); long startTime = Instant.now().minus(7, ChronoUnit.DAYS).toEpochMilli(); long endTime = Instant.now().toEpochMilli(); GetLogEventsRequest getLogEventsRequest = GetLogEventsRequest.builder() .logGroupName(logGroupName) .logStreamName(exactLogStreamName) // <-- exact name, not prefix .startTime(startTime) .endTime(endTime) .startFromHead(true) .build(); GetLogEventsResponse response = cloudWatchLogsClient.getLogEvents(getLogEventsRequest); if (response.events().isEmpty()) { System.out.println("No log events found in the past 7 days."); } else { response.events().forEach(e -> System.out.println(e.message())); } } catch (CloudWatchException e) { System.err.println(e.awsErrorDetails().errorMessage()); System.exit(1); } } }
  • Para obtener información sobre la API, consulte GetLogEvents en la Referencia de la API de AWS SDK for Java 2.x.

En el siguiente ejemplo de código, se muestra cómo utilizar PutSubscriptionFilter.

SDK para Java 2.x
nota

Hay más en GitHub. Busque el ejemplo completo y aprenda a configurar y ejecutar en el Repositorio de ejemplos de código de AWS.

import software.amazon.awssdk.regions.Region; import software.amazon.awssdk.services.cloudwatchlogs.CloudWatchLogsClient; import software.amazon.awssdk.services.cloudwatchlogs.model.CloudWatchLogsException; import software.amazon.awssdk.services.cloudwatchlogs.model.PutSubscriptionFilterRequest; /** * Before running this code example, you need to grant permission to CloudWatch * Logs the right to execute your Lambda function. * To perform this task, you can use this CLI command: * * aws lambda add-permission --function-name "lamda1" --statement-id "lamda1" * --principal "logs.us-west-2.amazonaws.com" --action "lambda:InvokeFunction" * --source-arn "arn:aws:logs:us-west-2:111111111111:log-group:testgroup:*" * --source-account "111111111111" * * Make sure you replace the function name with your function name and replace * '111111111111' with your account details. * For more information, see "Subscription Filters with AWS Lambda" in the * Amazon CloudWatch Logs Guide. * * * Also, before running this Java V2 code example,set up your development * environment,including your credentials. * * For more information,see the following documentation topic: * * https://docs.aws.amazon.com/sdk-for-java/latest/developer-guide/get-started.html * */ public class PutSubscriptionFilter { public static void main(String[] args) { final String usage = """ Usage: <filter> <pattern> <logGroup> <functionArn>\s Where: filter - A filter name (for example, myfilter). pattern - A filter pattern (for example, ERROR). logGroup - A log group name (testgroup). functionArn - An AWS Lambda function ARN (for example, arn:aws:lambda:us-west-2:111111111111:function:lambda1) . """; if (args.length != 4) { System.out.println(usage); System.exit(1); } String filter = args[0]; String pattern = args[1]; String logGroup = args[2]; String functionArn = args[3]; Region region = Region.US_WEST_2; CloudWatchLogsClient cwl = CloudWatchLogsClient.builder() .region(region) .build(); putSubFilters(cwl, filter, pattern, logGroup, functionArn); cwl.close(); } public static void putSubFilters(CloudWatchLogsClient cwl, String filter, String pattern, String logGroup, String functionArn) { try { PutSubscriptionFilterRequest request = PutSubscriptionFilterRequest.builder() .filterName(filter) .filterPattern(pattern) .logGroupName(logGroup) .destinationArn(functionArn) .build(); cwl.putSubscriptionFilter(request); System.out.printf( "Successfully created CloudWatch logs subscription filter %s", filter); } catch (CloudWatchLogsException e) { System.err.println(e.awsErrorDetails().errorMessage()); System.exit(1); } } }
  • Para obtener información sobre la API, consulte PutSubscriptionFilter en la Referencia de la API de AWS SDK for Java 2.x.

En el siguiente ejemplo de código, se muestra cómo utilizar StartLiveTail.

SDK para Java 2.x

Incluir los archivos requeridos.

import io.reactivex.FlowableSubscriber; import io.reactivex.annotations.NonNull; import org.reactivestreams.Subscription; import software.amazon.awssdk.auth.credentials.ProfileCredentialsProvider; import software.amazon.awssdk.services.cloudwatchlogs.CloudWatchLogsAsyncClient; import software.amazon.awssdk.services.cloudwatchlogs.model.LiveTailSessionLogEvent; import software.amazon.awssdk.services.cloudwatchlogs.model.LiveTailSessionStart; import software.amazon.awssdk.services.cloudwatchlogs.model.LiveTailSessionUpdate; import software.amazon.awssdk.services.cloudwatchlogs.model.StartLiveTailRequest; import software.amazon.awssdk.services.cloudwatchlogs.model.StartLiveTailResponseHandler; import software.amazon.awssdk.services.cloudwatchlogs.model.CloudWatchLogsException; import software.amazon.awssdk.services.cloudwatchlogs.model.StartLiveTailResponseStream; import java.util.Date; import java.util.List; import java.util.concurrent.atomic.AtomicReference;

Gestione los eventos de la sesión de Live Tail.

private static StartLiveTailResponseHandler getStartLiveTailResponseStreamHandler( AtomicReference<Subscription> subscriptionAtomicReference) { return StartLiveTailResponseHandler.builder() .onResponse(r -> System.out.println("Received initial response")) .onError(throwable -> { CloudWatchLogsException e = (CloudWatchLogsException) throwable.getCause(); System.err.println(e.awsErrorDetails().errorMessage()); System.exit(1); }) .subscriber(() -> new FlowableSubscriber<>() { @Override public void onSubscribe(@NonNull Subscription s) { subscriptionAtomicReference.set(s); s.request(Long.MAX_VALUE); } @Override public void onNext(StartLiveTailResponseStream event) { if (event instanceof LiveTailSessionStart) { LiveTailSessionStart sessionStart = (LiveTailSessionStart) event; System.out.println(sessionStart); } else if (event instanceof LiveTailSessionUpdate) { LiveTailSessionUpdate sessionUpdate = (LiveTailSessionUpdate) event; List<LiveTailSessionLogEvent> logEvents = sessionUpdate.sessionResults(); logEvents.forEach(e -> { long timestamp = e.timestamp(); Date date = new Date(timestamp); System.out.println("[" + date + "] " + e.message()); }); } else { throw CloudWatchLogsException.builder().message("Unknown event type").build(); } } @Override public void onError(Throwable throwable) { System.out.println(throwable.getMessage()); System.exit(1); } @Override public void onComplete() { System.out.println("Completed Streaming Session"); } }) .build(); }

Inicie la sesión de Live Tail.

CloudWatchLogsAsyncClient cloudWatchLogsAsyncClient = CloudWatchLogsAsyncClient.builder() .credentialsProvider(ProfileCredentialsProvider.create()) .build(); StartLiveTailRequest request = StartLiveTailRequest.builder() .logGroupIdentifiers(logGroupIdentifiers) .logStreamNames(logStreamNames) .logEventFilterPattern(logEventFilterPattern) .build(); /* Create a reference to store the subscription */ final AtomicReference<Subscription> subscriptionAtomicReference = new AtomicReference<>(null); cloudWatchLogsAsyncClient.startLiveTail(request, getStartLiveTailResponseStreamHandler(subscriptionAtomicReference));

Detenga la sesión de Live Tail una vez transcurrido un periodo de tiempo.

/* Set a timeout for the session and cancel the subscription. This will: * 1). Close the stream * 2). Stop the Live Tail session */ try { Thread.sleep(10000); } catch (InterruptedException e) { throw new RuntimeException(e); } if (subscriptionAtomicReference.get() != null) { subscriptionAtomicReference.get().cancel(); System.out.println("Subscription to stream closed"); }
  • Para obtener información acerca de la API, consulte StartLiveTail en la Referencia de la API de AWS SDK for Java 2.x.

Escenarios

El siguiente ejemplo de código muestra cómo crear una función de AWS Lambda invocada por un evento programado de Amazon EventBridge.

SDK para Java 2.x

Muestra cómo crear un evento programado de Amazon EventBridge que invoque una función de AWS Lambda. Configuración de EventBridge para que utilice una expresión cron para programar la invocación de la función de Lambda En este ejemplo, creará una función de Lambda utilizando la API de tiempo de ejecución de Java de Lambda. Este ejemplo invoca diferentes servicios de AWS para realizar un caso de uso específico. Este ejemplo indica cómo crear una aplicación que envíe un mensaje de texto a sus empleados para felicitarles por su primer aniversario.

Para ver el código fuente completo y las instrucciones de configuración y ejecución, consulte el ejemplo completo en GitHub.

Servicios utilizados en este ejemplo
  • Registros de CloudWatch

  • DynamoDB

  • EventBridge

  • Lambda

  • Amazon SNS