Services or capabilities described in Amazon Web Services documentation might vary by Region. To see the differences applicable to the China Regions, see Getting Started with Amazon Web Services in China (PDF).

End of support notice: On May 20, 2026, Amazon end support for Amazon IoT Events. After May 20, 2026, you will no longer be able to access the Amazon IoT Events console or Amazon IoT Events resources. For more information, visit this Amazon IoT Events end of support.

Creating a Lambda function in Amazon IoT Events

Amazon IoT Events provides a Lambda function that enables alarms to send and receive email and SMS notifications.

Requirements

The following requirements apply when you create a Lambda function for alarms:

For more information, see What is Amazon Lambda? in the Amazon Lambda Developer Guide.

CloudFormation template

Use the following CloudFormation template to create your Lambda function.

AWSTemplateFormatVersion: '2010-09-09'
Description: 'Notification Lambda for Alarm Model'
Resources:
  NotificationLambdaRole:
    Type: AWS::IAM::Role
    Properties:
      AssumeRolePolicyDocument:
        Statement:
          - Effect: Allow
            Principal:
              Service: lambda.amazonaws.com
            Action: sts:AssumeRole
      Path: "/"
      ManagedPolicyArns:
        - 'arn:aws-cn:iam::aws:policy/AWSLambdaExecute'
      Policies:
        - PolicyName: "NotificationLambda"
          PolicyDocument:
            Version: "2012-10-17"
            Statement:
              - Effect: "Allow"
                Action:
                  - "ses:GetIdentityVerificationAttributes"
                  - "ses:SendEmail"
                  - "ses:VerifyEmailIdentity"
                Resource: "*"
              - Effect: "Allow"
                Action:
                  - "sns:Publish"
                  - "sns:OptInPhoneNumber"
                  - "sns:CheckIfPhoneNumberIsOptedOut"
                  - "sms-voice:DescribeOptedOutNumbers"
                Resource: "*"
              - Effect: "Deny"
                Action:
                  - "sns:Publish"
                Resource: "arn:aws-cn:sns:*:*:*"
  NotificationLambdaFunction:              
    Type: AWS::Lambda::Function
    Properties:
      Role: !GetAtt NotificationLambdaRole.Arn
      Runtime: python3.7
      Handler: index.lambda_handler
      Timeout: 300
      MemorySize: 3008
      Code:
        ZipFile: |
          import boto3
          import json
          import logging
          import datetime
          logger = logging.getLogger()
          logger.setLevel(logging.INFO)
          ses = boto3.client('ses')
          sns = boto3.client('sns')
          def check_value(target):
            if target:
              return True
            return False

          # Check whether email is verified. Only verified emails are allowed to send emails to or from.
          def check_email(email):
            if not check_value(email):
              return False
            result = ses.get_identity_verification_attributes(Identities=[email])
            attr = result['VerificationAttributes']
            if (email not in attr or attr[email]['VerificationStatus'] != 'Success'):
                logging.info('Verification email for {} sent. You must have all the emails verified before sending email.'.format(email))
                ses.verify_email_identity(EmailAddress=email)
                return False
            return True

          # Check whether the phone holder has opted out of receiving SMS messages from your account
          def check_phone_number(phone_number):
            try:
              result = sns.check_if_phone_number_is_opted_out(phoneNumber=phone_number)
              if (result['isOptedOut']):
                  logger.info('phoneNumber {} is not opt in of receiving SMS messages. Phone number must be opt in first.'.format(phone_number))
                  return False
              return True
            except Exception as e:
              logging.error('Your phone number {} must be in E.164 format in SSO. Exception thrown: {}'.format(phone_number, e))
              return False

          def check_emails(emails):
            result = True
            for email in emails:
                if not check_email(email):
                    result = False
            return result

          def lambda_handler(event, context):
            logging.info('Received event: ' + json.dumps(event))
            nep = json.loads(event.get('notificationEventPayload'))
            alarm_state = nep['alarmState']
            default_msg = 'Alarm ' + alarm_state['stateName'] + '\n'
            timestamp = datetime.datetime.utcfromtimestamp(float(nep['stateUpdateTime'])/1000).strftime('%Y-%m-%d %H:%M:%S')
            alarm_msg = "{} {} {} at {} UTC ".format(nep['alarmModelName'], nep.get('keyValue', 'Singleton'), alarm_state['stateName'], timestamp)
            default_msg += 'Sev: ' + str(nep['severity']) + '\n'
            if (alarm_state['ruleEvaluation']):
              property = alarm_state['ruleEvaluation']['simpleRule']['inputProperty']
              default_msg += 'Current Value: ' + str(property) + '\n'
              operator = alarm_state['ruleEvaluation']['simpleRule']['operator']
              threshold = alarm_state['ruleEvaluation']['simpleRule']['threshold']
              alarm_msg += '({} {} {})'.format(str(property), operator, str(threshold))
            default_msg += alarm_msg + '\n'

            emails = event.get('emailConfigurations', [])
            logger.info('Start Sending Emails')
            for email in emails:
              from_adr = email.get('from')
              to_adrs = email.get('to', [])
              cc_adrs = email.get('cc', [])
              bcc_adrs = email.get('bcc', [])
              msg = default_msg + '\n' + email.get('additionalMessage', '')
              subject = email.get('subject', alarm_msg)
              fa_ver = check_email(from_adr)
              tas_ver = check_emails(to_adrs)
              ccas_ver = check_emails(cc_adrs)
              bccas_ver = check_emails(bcc_adrs)
              if (fa_ver and tas_ver and ccas_ver and bccas_ver):
                ses.send_email(Source=from_adr,
                               Destination={'ToAddresses': to_adrs, 'CcAddresses': cc_adrs, 'BccAddresses': bcc_adrs},
                               Message={'Subject': {'Data': subject}, 'Body': {'Text': {'Data': msg}}})
                logger.info('Emails have been sent')

            logger.info('Start Sending SNS message to SMS')
            sns_configs = event.get('smsConfigurations', [])
            for sns_config in sns_configs:
              sns_msg = default_msg + '\n' + sns_config.get('additionalMessage', '')
              phone_numbers = sns_config.get('phoneNumbers', [])
              sender_id = sns_config.get('senderId')
              for phone_number in phone_numbers:
                  if check_phone_number(phone_number):
                    if check_value(sender_id):
                      sns.publish(PhoneNumber=phone_number, Message=sns_msg, MessageAttributes={'AWS.SNS.SMS.SenderID':{'DataType': 'String','StringValue': sender_id}})
                    else:
                      sns.publish(PhoneNumber=phone_number, Message=sns_msg)
                    logger.info('SNS messages have been sent')