使用 PutLogEvents API 发送手动创建的嵌入式指标格式日志

您可以使用 CloudWatch Logs PutLogEvents API 将嵌入式指标格式日志发送到 CloudWatch Logs。在调用 PutLogEvents 时，您需要包含以下 HTTP 标头以指示 CloudWatch Logs 应提取指标。

x-amzn-logs-format: json/emf

以下是使用 Amazon SDK for Java 2.x 的完整示例：

package org.example.basicapp;

import software.amazon.awssdk.regions.Region;
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.InputLogEvent;
import software.amazon.awssdk.services.cloudwatchlogs.model.PutLogEventsRequest;

import java.util.Collections;

public class EmbeddedMetricsExample {
        public static void main(String[] args) {

                final String usage = "To run this example, supply a Region code (eg. us-east-1), log group, and stream name as command line arguments"
                                + "Ex: PutLogEvents <region-id> <log-group-name> <stream-name>";

                if (args.length != 3) {
                        System.out.println(usage);
                        System.exit(1);
                }

                String regionId = args[0];
                String logGroupName = args[1];
                String logStreamName = args[2];

                CloudWatchLogsClient logsClient = CloudWatchLogsClient.builder().region(Region.of(regionId)).build();

                // A sequence token is required to put a log event in an existing stream.
                // Look up the stream to find its sequence token.
                String sequenceToken = getNextSequenceToken(logsClient, logGroupName, logStreamName);

                // Build a JSON log using the EmbeddedMetricFormat.
                long timestamp = System.currentTimeMillis();
                String message = "{" +
                                "  \"_aws\": {" +
                                "    \"Timestamp\": " + timestamp  + "," +
                                "    \"CloudWatchMetrics\": [" +
                                "      {" +
                                "        \"Namespace\": \"MyApp\"," +
                                "        \"Dimensions\": [[\"Operation\"], [\"Operation\", \"Cell\"]]," +
                                "        \"Metrics\": [{ \"Name\": \"ProcessingLatency\", \"Unit\": \"Milliseconds\" }]" +
                                "      }" +
                                "    ]" +
                                "  }," +
                                "  \"Operation\": \"Aggregator\"," +
                                "  \"Cell\": \"001\"," +
                                "  \"ProcessingLatency\": 100" +
                                "}";
                InputLogEvent inputLogEvent = InputLogEvent.builder()
                        .message(message)
                        .timestamp(timestamp)
                        .build();

                // Specify the request parameters.
                PutLogEventsRequest putLogEventsRequest = PutLogEventsRequest.builder()
                        .overrideConfiguration(builder ->
                                // provide the log-format header of json/emf
                                builder.headers(Collections.singletonMap("x-amzn-logs-format",  Collections.singletonList("json/emf"))))
                        .logEvents(Collections.singletonList(inputLogEvent))
                        .logGroupName(logGroupName)
                        .logStreamName(logStreamName)
                        .sequenceToken(sequenceToken)
                        .build();

                logsClient.putLogEvents(putLogEventsRequest);

                System.out.println("Successfully put CloudWatch log event");
        }

        private static String getNextSequenceToken(CloudWatchLogsClient logsClient, String logGroupName, String logStreamName) {
                DescribeLogStreamsRequest logStreamRequest = DescribeLogStreamsRequest.builder()
                        .logGroupName(logGroupName)
                        .logStreamNamePrefix(logStreamName)
                        .build();

                DescribeLogStreamsResponse describeLogStreamsResponse = logsClient.describeLogStreams(logStreamRequest);

                // Assume that a single stream is returned since a specific stream name was
                // specified in the previous request.
                return describeLogStreamsResponse.logStreams().get(0).uploadSequenceToken();
        }
}