AWS lambdaを使用してアラートの件名・本文をカスタマイズする

private createRedshiftAlarms(lambdaFunction: IFunction, clusterId: string) {
    const healthStatusAlarm = new cloudwatch.Alarm(this, `RedshiftHealthStatusAlarm`, {
      metric: new cloudwatch.Metric({
        namespace: 'AWS/Redshift',
        metricName: 'HealthStatus',
        dimensionsMap: { ClusterIdentifier: clusterId },
        statistic: 'Minimum',
      }),
      threshold: 1,
      comparisonOperator: cloudwatch.ComparisonOperator.LESS_THAN_THRESHOLD,
      evaluationPeriods: 1,
      alarmDescription: 'クラスタのヘルスステータスが不健康な場合にアラーム',
    });

    healthStatusAlarm.addAlarmAction(new cloudwatchActions.LambdaAction(lambdaFunction));
  }

private createGlueAlarms(lambdaFunction: IFunction, JobName: string) {
    // Glue ジョブが失敗またはタイムアウトした場合のルール
    const failedRule = new events.Rule(this, 'GluePythonShellFailedEvent', {
      eventPattern: {
        source: ['aws.glue'],
        detailType: ['Glue Job State Change'],
        detail: {
          state: ['FAILED', 'TIMEOUT'],
        },
      },
      targets: [new events_targets.LambdaFunction(lambdaFunction)],
    });

const EmailContentFormatterFunction = new NodejsFunction(this, 'EmailContentFormatter', {
      functionName: 'EmailContentFormatter',
      entry: './function/handler.ts',
      handler: 'index.handler',
      runtime: Runtime.NODEJS_20_X,
      environment: {
        ENV: environment,
        SNS_TOPIC_ARN: alarmTopicArn,
      },
      deadLetterTopic: Topic.fromTopicArn(this, 'DeadLetterTopic', alarmTopicArn),
    });

    new cdk.CfnOutput(this, 'EmailContentFormatterFunctionArn', {
      value: EmailContentFormatterFunction.functionArn,
      exportName: 'EmailContentFormatterFunctionArn',
    });

    EmailContentFormatterFunction.addToRolePolicy(new iam.PolicyStatement({
      actions: ['sns:Publish'],
      resources: [alarmTopicArn],
    }));

    // EventBridgeからLambdaを呼び出す権限を付与
    EmailContentFormatterFunction.addPermission('AllowEventBridgeInvoke', {
      principal: new iam.ServicePrincipal('events.amazonaws.com'),
      action: 'lambda:InvokeFunction',
      sourceArn: cdk.Stack.of(this).formatArn({
        service: 'events',
        resource: '*',
      }),
    });

import { SNSClient, PublishCommand } from "@aws-sdk/client-sns";

// SNSクライアントの初期化
const snsClient = new SNSClient({});

export const handler = async (event: any, context: any) => {
    // 受け取ったイベントをJSON文字列としてフォーマット
    const formattedMessage = JSON.stringify(event, null, 4);

    // イベント詳細に基づいてメッセージタイプを決定
    const detailType = event['detail-type'] || '';
    const source = event['source'] || '';

    // イベントのタイプに応じてメッセージタイプを設定
    let messageType: string = ''; // 空で文字列型として定義
    if (source === "aws.cloudwatch" && 'alarmArn' in event) {
        messageType = "Redshiftアラート通知";
    } else if (detailType === "Glue Job State Change") {
        const state = event.detail?.state || '';
        if (state === "SUCCEEDED") {
            messageType = "Glueジョブ成功";
        } else if (state === "FAILED") {
            messageType = "Glueジョブ失敗";
        } else {
            messageType = "Glueジョブ状態不明";
        }
    } else {
        messageType = "通知"; // 最後のelseで「通知」とする
    }

    // 環境変数から環境名を取得
    const env = process.env.ENV || '';
    const topicArn = process.env.SNS_TOPIC_ARN;

    // 環境名に基づいて件名の環境部分を決定
    let environmentName: string = ''; // 空で文字列型として定義
    if (env === 'dev') {
        environmentName = "開発環境";
    } else if (env === 'stg') {
        environmentName = "検証環境";
    } else if (env === 'prod') {
        environmentName = "本番環境";
    } else {
        environmentName = "テスト環境"; 
    }

    // SNSメッセージの件名をカスタマイズ
    const subject = `${environmentName} ${messageType}`;

    // SNSトピックにメッセージを公開
    try {
        await snsClient.send(new PublishCommand({
            TopicArn: topicArn,
            Subject: subject,
            Message: formattedMessage
        }));

        return {
            statusCode: 200,
            body: JSON.stringify('Notification sent successfully!')
        };
    } catch (error) {
        console.error('Error publishing to SNS:', error);
        return {
            statusCode: 500,
            body: JSON.stringify('Failed to send notification.')
        };
    }
};