AWSTemplateFormatVersion: '2010-09-09'
Transform: AWS::Serverless-2016-10-31
Description: hexagonal-arch-sample
  
Globals:
  Function:
    Timeout: 20

Resources:
  #DynamoDB table
  StocksTable:
    Type: AWS::DynamoDB::Table
    Properties:
      AttributeDefinitions:
      - AttributeName: STOCK_ID
        AttributeType: S
      KeySchema:
      - AttributeName: STOCK_ID
        KeyType: HASH
      BillingMode: PAY_PER_REQUEST
  #Network configuration
  Vpc:
    Type: AWS::EC2::VPC
    Properties:
      CidrBlock: '10.0.0.0/16'
      
  SecurityGroup:
    Type: AWS::EC2::SecurityGroup
    Properties:
      GroupDescription: 'Lambda Security Group'
      VpcId: !Ref Vpc
      SecurityGroupEgress:
        - CidrIp: '0.0.0.0/0'
          FromPort: 0
          ToPort: 65535
          IpProtocol: tcp
      SecurityGroupIngress:
        - CidrIp: '0.0.0.0/0'
          FromPort: 0
          ToPort: 65535
          IpProtocol: tcp
  SubnetA:
    Type: AWS::EC2::Subnet
    Properties:
      VpcId: !Ref Vpc
      AvailabilityZone: !Select [ 0, !GetAZs '' ]
      MapPublicIpOnLaunch: false
      CidrBlock: '10.0.0.0/24'
  SubnetB:
    Type: AWS::EC2::Subnet
    Properties:
      VpcId: !Ref Vpc
      AvailabilityZone: !Select [ 1, !GetAZs '' ]
      MapPublicIpOnLaunch: false
      CidrBlock: '10.0.1.0/24'
  SubnetC:
    Type: AWS::EC2::Subnet
    Properties:
      VpcId: !Ref Vpc
      AvailabilityZone: !Select [ 2, !GetAZs '' ]
      MapPublicIpOnLaunch: false
      CidrBlock: '10.0.2.0/24'
      
  RouteTable:
    Type: AWS::EC2::RouteTable
    Properties:
      VpcId: !Ref Vpc

  PublicSubnetCRouteTableAssociation:
    Type: AWS::EC2::SubnetRouteTableAssociation
    Properties:
      SubnetId: !Ref SubnetC
      RouteTableId: !Ref RouteTable

  InternetGateway:
    Type: 'AWS::EC2::InternetGateway'

  VPCGatewayAttachment:
    Type: 'AWS::EC2::VPCGatewayAttachment'
    Properties:
      VpcId: !Ref Vpc
      InternetGatewayId: !Ref InternetGateway
    
  InternetRoute:
    Type: 'AWS::EC2::Route'
    Properties:
      DestinationCidrBlock: '0.0.0.0/0'
      GatewayId: !Ref InternetGateway
      RouteTableId: !Ref RouteTable

  EIP:
    Type: 'AWS::EC2::EIP'
    Properties:
      Domain: 'vpc'

  Nat:
    Type: 'AWS::EC2::NatGateway'
    Properties:
      AllocationId: !GetAtt EIP.AllocationId
      SubnetId: !Ref SubnetC

  NatRouteTable:
    Type: 'AWS::EC2::RouteTable'
    Properties:
      VpcId: !Ref Vpc

  NatRoute:
    Type: 'AWS::EC2::Route'
    Properties:
      DestinationCidrBlock: '0.0.0.0/0'
      NatGatewayId: !Ref Nat
      RouteTableId: !Ref NatRouteTable

  SubnetARouteTableAssociation:
    Type: 'AWS::EC2::SubnetRouteTableAssociation'
    Properties:
      RouteTableId: !Ref NatRouteTable
      SubnetId: !Ref SubnetA

  SubnetBRouteTableAssociation:
    Type: 'AWS::EC2::SubnetRouteTableAssociation'
    Properties:
      RouteTableId: !Ref NatRouteTable
      SubnetId: !Ref SubnetB

  DDBEndpoint:
    Type: 'AWS::EC2::VPCEndpoint'
    Properties:
      PolicyDocument:
        Version: 2012-10-17
        Statement:
          - Effect: Allow
            Principal: '*'
            Action:
              - 'dynamodb:GetItem'
              - 'dynamodb:DescribeTable'
            Resource:
              - '*'
      ServiceName: !Sub 'com.amazonaws.${AWS::Region}.dynamodb'
      RouteTableIds:
        - !Ref NatRouteTable
      VpcId: !Ref Vpc
      
  InstanceSecurityGroup:
    Type: 'AWS::EC2::SecurityGroup'
    Properties:
      GroupName: 'Security Group for outbound traffic'
      GroupDescription: 'Lambda Traffic'
      VpcId: !Ref Vpc
      SecurityGroupEgress:
      - IpProtocol: '-1'
        CidrIp: '0.0.0.0/0'

  InstanceSecurityGroupIngress:
    Type: 'AWS::EC2::SecurityGroupIngress'
    DependsOn: 'InstanceSecurityGroup'
    Properties:
      GroupId: !Ref InstanceSecurityGroup
      IpProtocol: 'tcp'
      FromPort: 0
      ToPort: 65535
      SourceSecurityGroupId: !Ref InstanceSecurityGroup
  #ElastiCache Redis
  ElastiCacheSubnetGroup:
    Type: 'AWS::ElastiCache::SubnetGroup'
    Properties:
      Description: Cache Subnet Group
      SubnetIds:
        - !Ref SubnetA
        - !Ref SubnetB
  ElastiCacheRedisCluster:
    Type: AWS::ElastiCache::ReplicationGroup
    Properties:
      AutoMinorVersionUpgrade: true
      AtRestEncryptionEnabled: true
      CacheNodeType: cache.t2.micro
      CacheSubnetGroupName: !Ref ElastiCacheSubnetGroup
      Engine: redis
      NumNodeGroups: 1
      Port: 6379
      ReplicasPerNodeGroup: 1
      ReplicationGroupDescription: cache-aside pattern with Redis
      SecurityGroupIds:
        - !Ref InstanceSecurityGroup

  #Lambda function
  StocksConverterFunction:
    Type: AWS::Serverless::Function
    DependsOn: ElastiCacheRedisCluster
    Properties:
      CodeUri: hexagonal-architecture/
      Handler: app.lambdaHandler
      Runtime: nodejs18.x
      MemorySize: 256
      Policies:
        - DynamoDBReadPolicy:
            TableName: !Ref StocksTable
        - Version: '2012-10-17'
          Statement:
            - Effect: Allow
              Action:
                - 'logs:CreateLogGroup'
                - 'logs:CreateLogStream'
                - 'logs:PutLogEvents'
                - 'ec2:CreateNetworkInterface'
                - 'ec2:DescribeNetworkInterfaces'
                - 'ec2:DeleteNetworkInterface'
                - 'ec2:AssignPrivateIpAddresses'
                - 'ec2:UnassignPrivateIpAddresses'
              Resource: '*'
      Environment:
        Variables:
          DB_TABLE: !Ref StocksTable
          CACHE_URL: !GetAtt ElastiCacheRedisCluster.PrimaryEndPoint.Address
          CACHE_PORT: !GetAtt ElastiCacheRedisCluster.PrimaryEndPoint.Port
          # change with a mock API URL or an 3rd Party API
          # CURRENCIES_PATH: 'https://www.myAPI.com'
      VpcConfig:
        SecurityGroupIds:
          - !Ref InstanceSecurityGroup
        SubnetIds:
          - !Ref SubnetA
          - !Ref SubnetB
      Events:
        StocksConverter:
          Type: HttpApi 
          Properties:
            ApiId: !Ref StocksGateway
            Path: /stock/{StockID}
            Method: get
#HTTP API Gateway
  StocksGateway:
    Type: AWS::Serverless::HttpApi
    Properties:
      CorsConfiguration:
        AllowMethods:
          - GET
          - POST
        AllowOrigins:
          - '*'

Outputs:
  HttpApiUrl:
    Description: URL of your API endpoint, add stock ID like AMZN
    Value:
      Fn::Sub: 'https://${StocksGateway}.execute-api.${AWS::Region}.${AWS::URLSuffix}/stock/'