Description: SAM + Lambda + EFS

Parameters:
  PreCreatedSubnetOne:
    Type: String
  PreCreatedVpc:
    Type: String

Resources:
  EfsFileSystem:
    Type: AWS::EFS::FileSystem

  MountTarget:
    Type: AWS::EFS::MountTarget
    Properties:
      FileSystemId:
        Ref: EfsFileSystem
      SubnetId:
        Ref: PreCreatedSubnetOne
      SecurityGroups:
      - Fn::GetAtt: MySecurityGroup.GroupId

  AccessPoint:
    Type: AWS::EFS::AccessPoint
    Properties:
      FileSystemId:
        Ref: EfsFileSystem

  LambdaFunctionWithEfs:
    Type: AWS::Serverless::Function
    DependsOn: MountTarget
    Properties:
      InlineCode: |
        const fs = require('fs')
        const path = require('path')
        const efsMountPath = '/mnt/efs'

        exports.handler = async (event, context, callback) => {
        const directory = path.join(efsMountPath, event.body)
        const files = fs.readdirSync(directory)
        return files
        }
      Handler: index.handler
      MemorySize: 128
      Runtime: nodejs14.x
      Timeout: 3
      VpcConfig:
        SecurityGroupIds:
        - Fn::GetAtt: MySecurityGroup.GroupId
        SubnetIds:
        - Ref: PreCreatedSubnetOne
      FileSystemConfigs:
      - Arn:
          Fn::GetAtt: AccessPoint.Arn
        LocalMountPath: /mnt/EFS

  MySecurityGroup:
    Type: AWS::EC2::SecurityGroup
    Properties:
      GroupDescription: my test group
      VpcId:
        Ref: PreCreatedVpc
Metadata:
  SamTransformTest: true