

Doc AWS SDK 예제 GitHub 리포지토리에서 더 많은 SDK 예제를 사용할 수 있습니다. [AWS](https://github.com/awsdocs/aws-doc-sdk-examples) 

기계 번역으로 제공되는 번역입니다. 제공된 번역과 원본 영어의 내용이 상충하는 경우에는 영어 버전이 우선합니다.

# AWS SDK 또는 CLI와 `DescribeLogStreams` 함께 사용
<a name="cloudwatch-logs_example_cloudwatch-logs_DescribeLogStreams_section"></a>

다음 코드 예시는 `DescribeLogStreams`의 사용 방법을 보여 줍니다.

------
#### [ CLI ]

**AWS CLI**  
다음 명령은 로그 그룹 `my-logs`의 `2015` 접두사로 시작하는 모든 로그 스트림을 보여 줍니다.  

```
aws logs describe-log-streams --log-group-name my-logs --log-stream-name-prefix 2015
```
출력:  

```
{
    "logStreams": [
        {
            "creationTime": 1433189871774,
            "arn": "arn:aws:logs:us-west-2:0123456789012:log-group:my-logs:log-stream:20150531",
            "logStreamName": "20150531",
            "storedBytes": 0
        },
        {
            "creationTime": 1433189873898,
            "arn": "arn:aws:logs:us-west-2:0123456789012:log-group:my-logs:log-stream:20150601",
            "logStreamName": "20150601",
            "storedBytes": 0
        }
    ]
}
```
+  API 세부 정보는 *AWS CLI 명령 참조*의 [DescribeLogStreams](https://awscli.amazonaws.com/v2/documentation/api/latest/reference/logs/describe-log-streams.html)를 참조하세요.

------
#### [ Java ]

**SDK for Java 2.x**  
 GitHub에 더 많은 내용이 있습니다. [AWS 코드 예 리포지토리](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/javav2/example_code/cloudwatch-logs#code-examples)에서 전체 예를 찾고 설정 및 실행하는 방법을 배워보세요.
지정된 접두사와 일치하는 지정된 로그 그룹 내의 로그 스트림을 검색합니다.  

```
/**
 * 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
        }
    }
}
```
지정된 로그 그룹의 최신 로그 스트림에 대한 메타데이터를 출력합니다.  

```
/**
 * 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());
        }
    }
}
```
+  API 세부 정보는 *AWS SDK for Java 2.x API 참조*의 [DescribeLogStreams](https://docs.aws.amazon.com/goto/SdkForJavaV2/logs-2014-03-28/DescribeLogStreams)을 참조하세요.

------