如何通过AWS Lambda将CloudWatch告警状态上传至S3存储桶？

我已经实现了查询CloudWatch告警的代码，可在控制台按预期格式输出告警状态，现在希望将该输出作为文本文件上传至S3存储桶，请问如何实现？

已实现的CloudWatch告警查询代码 #

import { CloudWatchClient, DescribeAlarmsCommand } from "@aws-sdk/client-cloudwatch";
const REGION = "eu-west-2";

const cwclient = new CloudWatchClient({ region: REGION });

export const handler = async() => {
  
const cwparams = {};
const cw = new DescribeAlarmsCommand(cwparams);

try {
  const cwdata = await cwclient.send(cw);
  cwdata.MetricAlarms.forEach(function (item) {
      console.log('\n%j', {alarmname:item.AlarmName,alarmstate:item.StateValue});
    });
  
} catch (error) {

  }
};

代码输出 #

Function Logs
START RequestId: xxxxxxxxxxxxxxxxxxx Version: $LATEST
2022-11-30T09:48:34.655Z    xxxxxxxxxxxxxxxxxxx INFO    
{"alarmname":"my-alarm-1","alarmstate":"OK"}
2022-11-30T09:48:34.655Z    xxxxxxxxxxxxxxxxxxx INFO    
{"alarmname":"my-alarm-2","alarmstate":"OK"}
END RequestId: xxxxxxxxxxxxxxxxxxx

已测试的S3上传代码 #

我已查看S3 PutObjectCommand的SDK文档并测试了以下代码，可上传含文本内容的文件，但不确定如何将CloudWatch告警数据与该代码结合，使文本文件的Body为CloudWatch告警数据。

import { S3Client, PutObjectCommand } from "@aws-sdk/client-s3";

export const handler = async() => {

const bucketName = "mybucket";
const keyName = "test.json";

const s3 = new S3Client({});

const s3putCommand = new PutObjectCommand({
  Bucket: bucketName,
  Key: keyName,
  Body: "Hello"  // 我希望此处为CloudWatch告警数据
});

try {
    await s3.send(s3putCommand);
    console.log('Successfully uploaded data to ' + bucketName + '/' + keyName);
  
} catch (error) {
  
  }
};

代码输出 #

Function Logs
START RequestId: xxxxxxxxxxxxxxxxxxx Version: $LATEST
2022-11-30T09:56:45.585Z    xxxxxxxxxxxxxxxxxxx INFO    Successfully uploaded data to mybucket/test.json
END RequestId: xxxxxxxxxxxxxxxxxxx

目标效果 #

我希望上传的test.json文件内容如下：

{"alarmname":"my-alarm-1","alarmstate":"OK"} {"alarmname":"my-alarm-2","alarmstate":"OK"}

将两段代码整合，先获取CloudWatch告警数据并格式化为目标字符串，再将该字符串作为S3上传请求的Body参数即可。以下是整合后的完整代码：

import { CloudWatchClient, DescribeAlarmsCommand } from "@aws-sdk/client-cloudwatch";
import { S3Client, PutObjectCommand } from "@aws-sdk/client-s3";

const REGION = "eu-west-2";
const bucketName = "mybucket";
const keyName = "test.json";

// 初始化CloudWatch和S3客户端
const cwclient = new CloudWatchClient({ region: REGION });
const s3 = new S3Client({});

export const handler = async() => {
  try {
    // 1. 获取CloudWatch告警数据
    const cwparams = {};
    const cwCommand = new DescribeAlarmsCommand(cwparams);
    const cwdata = await cwclient.send(cwCommand);

    // 2. 格式化告警数据为目标字符串
    const alarmStrings = cwdata.MetricAlarms.map(item => 
      JSON.stringify({alarmname: item.AlarmName, alarmstate: item.StateValue})
    );
    const bodyContent = alarmStrings.join(' ');

    // 3. 上传至S3
    const s3putCommand = new PutObjectCommand({
      Bucket: bucketName,
      Key: keyName,
      Body: bodyContent,
      ContentType: 'text/plain' // 可选，指定文件类型
    });
    await s3.send(s3putCommand);

    console.log('Successfully uploaded alarm data to ' + bucketName + '/' + keyName);
    console.log('Uploaded content:', bodyContent);
  } catch (error) {
    console.error('Error occurred:', error);
  }
};

代码说明 #

• 先通过CloudWatch客户端获取告警数据，使用map方法将每个告警对象转为JSON字符串
• 使用join(' ')将所有JSON字符串用空格拼接，匹配你想要的文件格式
• 将拼接后的字符串作为PutObjectCommand的Body参数，完成上传
• 添加了ContentType参数（可选），明确文件类型为文本；如果后续需要按标准JSON解析，建议将格式调整为数组形式[{}, {}]，并将ContentType改为application/json

内容的提问来源于stack exchange，提问作者jtwp