GetLogEvents与 AWS SDK 或 CLI 配合使用

以下命令从日志组 my-logs 中名为 20150601 的日志流中检索日志事件：

aws logs get-log-events --log-group-name my-logs --log-stream-name 20150601

输出：

{
    "nextForwardToken": "f/31961209122447488583055879464742346735121166569214640130",
    "events": [
        {
            "ingestionTime": 1433190494190,
            "timestamp": 1433190184356,
            "message": "Example Event 1"
        },
        {
            "ingestionTime": 1433190516679,
            "timestamp": 1433190184356,
            "message": "Example Event 1"
        },
        {
            "ingestionTime": 1433190494190,
            "timestamp": 1433190184358,
            "message": "Example Event 2"
        }
    ],
    "nextBackwardToken": "b/31961209122358285602261756944988674324553373268216709120"
}

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);
        }
    }
}