AWSTemplateFormatVersion: '2010-09-09'
Parameters:
  SecurityGroupId:
    Description: the SG this function should run in to have connectivity to MySQL
    Type: String
  SubnetId:
    Description: the Subnet this function should run in to have connectivity to MySQL
    Type: String
Resources:
  LambdaRole:
    Type: AWS::IAM::Role
    Properties:
      AssumeRolePolicyDocument:
          Version: 2012-10-17
          Statement:
            -
              Effect: Allow
              Principal:
                Service:
                  - lambda.amazonaws.com
              Action:
                - sts:AssumeRole
      Path: /
      Policies:
          -
            PolicyName: CloudwatchLogs
            PolicyDocument:
              Version: 2012-10-17
              Statement:
                -
                  Effect: Allow
                  Action:
                    - logs:CreateLogGroup
                  Resource:
                    - !Sub "arn:aws:logs:${AWS::Region}:${AWS::AccountId}:*"
                -
                  Effect: Allow
                  Action:
                    - logs:CreateLogStream
                    - logs:PutLogEvents
                  Resource:
                    - !Sub "arn:aws:logs:${AWS::Region}:${AWS::AccountId}:log-group:/aws/lambda/*"
                -
                  Effect: Allow
                  Action:
                    - dynamodb:DescribeTable
                    - dynamodb:GetItem
                  Resource:
                    - !Sub "arn:aws:dynamodb:${AWS::Region}:${AWS::AccountId}:table/*"
  LambdaUDFFunction:
     Type: "AWS::Lambda::Function"
     Properties:
       FunctionName: f-dynamodb-lookup-python-varchar-varchar-varchar
       Role: !GetAtt 'LambdaRole.Arn'
       Handler: index.handler
       Runtime: python3.9
       Timeout: 300
       Code:
         ZipFile: |
            import json
            import boto3
            dynamodb = boto3.resource('dynamodb')

            def handler(event, context):
             print("Received event: " + json.dumps(event, indent=2))
             ret = dict()
             try:
              tableName = event["arguments"][0][0]
              columnName = event["arguments"][0][1]

              table = dynamodb.Table(tableName)
              table.item_count
              res = []
              for argument in event['arguments']:
               try:
                columnValue = argument[2]
                response = table.get_item(Key={columnName: columnValue })
                res.append(json.dumps(response["Item"]))
               except:
                res.append(None)
              ret['success'] = True
              ret['results'] = res
             except Exception as e:
              ret['success'] = False
              ret['error_msg'] = str(e)
             return json.dumps(ret)