const alarm = new cdk.aws_cloudwatch.Alarm(this, 'Errors', {
      comparisonOperator: cdk.aws_cloudwatch.ComparisonOperator.GREATER_THAN_THRESHOLD,
      threshold: 1,
      evaluationPeriods: 1,
      metric: alias.metricErrors({period: cdk.Duration.minutes(1)}),
      actionsEnabled: true,
      treatMissingData: cdk.aws_cloudwatch.TreatMissingData.NOT_BREACHING
    });
    const sns = new cdk.aws_sns.Topic(this, 'Topic', {
      displayName: 'alarmTopic',
    });
    alarmLambda.addPermission('addCloudWatch', {
      principal: new cdk.aws_iam.ServicePrincipal('lambda.alarms.cloudwatch.amazonaws.com'),
      sourceAccount: this.account,
      sourceArn: alarm.alarmArn,
      action: 'lambda:InvokeFunction',
    });
    alarm.addAlarmAction(new cdk.aws_cloudwatch_actions.SnsAction(sns));
    this.node.tryRemoveChild(sns.node.id);
    (alarm.node.defaultChild as cdk.aws_cloudwatch.CfnAlarm).addPropertyOverride(
      'AlarmActions',  [alarmLambda.functionArn]
    )