AWSTemplateFormatVersion: '2010-09-09'
Parameters:
  ClusterNodeType:
    Description: The compute and memory capacity of the nodes in the Redis Cluster
    Type: String
    Default: cache.t2.small
    AllowedValues:
    - cache.t2.small
    - cache.m1.small
    - cache.m1.large
  ApplicationInstanceType:
    Description: The compute and memory capacity of the application's EC2 instance type
    Type: String
    Default: t2.micro
    AllowedValues:
    - t2.micro
  ApplicationAutoScalingMinSize:
    Description: The minimum number of instances in the application auto scaling group
    Type: Number
    Default: 2
    MinValue: 2
  ApplicationAutoScalingMaxSize:
    Description: The maximum number of instances in the application auto scaling group
    Type: Number
    Default: 2
    MinValue: 2
  KeyName:
    Description: Name of an existing EC2 KeyPair to enable SSH access to the instance
    Type: AWS::EC2::KeyPair::KeyName
    ConstraintDescription: Must be the name of an existing EC2 KeyPair.
Outputs:
  ApplicationUrl:
    Description: The URL to the load balancer for the application
    Value: !GetAtt ChatEnvironment.EndpointURL
Resources:
  RedisCluster:
    Type: AWS::ElastiCache::CacheCluster
    Properties:
      CacheNodeType: !Ref ClusterNodeType
      VpcSecurityGroupIds:
      - !GetAtt CacheSecurityGroup.GroupId
      Engine: redis
      NumCacheNodes: 1
  CacheSecurityGroup:
    Type: AWS::EC2::SecurityGroup
    Properties:
      GroupDescription: Cache security group
  CacheSecurityGroupIngress:
    Type: AWS::EC2::SecurityGroupIngress
    Properties:
      GroupId: !GetAtt CacheSecurityGroup.GroupId
      IpProtocol: tcp
      FromPort: !GetAtt RedisCluster.RedisEndpoint.Port
      ToPort: !GetAtt RedisCluster.RedisEndpoint.Port
      SourceSecurityGroupId: !GetAtt ApplicationSecurityGroup.GroupId
  ChatApplication:
    Type: AWS::ElasticBeanstalk::Application
    Properties:
      Description: AWS Elastic Beanstalk Chat Application
  ChatApplicationVersion:
    Type: AWS::ElasticBeanstalk::ApplicationVersion
    Properties:
      ApplicationName: !Ref ChatApplication
      Description: AWS ElasticBeanstalk Chat Application Version
      SourceBundle:
        S3Bucket: elasticache-refarch-chatapp
        S3Key: chatapp.zip
  ChatConfigurationTemplate:
    Type: AWS::ElasticBeanstalk::ConfigurationTemplate
    Properties:
      ApplicationName: !Ref ChatApplication
      Description: AWS ElasticBeanstalk Chat Configuration Template
      PlatformArn: arn:aws:elasticbeanstalk:us-east-1::platform/Node.js running on 64bit Amazon Linux
      OptionSettings:
      - Namespace: aws:autoscaling:asg
        OptionName: MinSize
        Value: !Ref ApplicationAutoScalingMinSize
      - Namespace: aws:autoscaling:asg
        OptionName: MaxSize
        Value: !Ref ApplicationAutoScalingMaxSize
      - Namespace: aws:elasticbeanstalk:environment
        OptionName: EnvironmentType
        Value: LoadBalanced
      - Namespace: aws:elasticbeanstalk:environment
        OptionName: ServiceRole
        Value: aws-elasticbeanstalk-service-role
      - Namespace: aws:elasticbeanstalk:environment
        OptionName: LoadBalancerType
        Value: application
      - Namespace: aws:elasticbeanstalk:environment:process:default
        OptionName: StickinessEnabled
        Value: 'true'
      - Namespace: aws:elasticbeanstalk:healthreporting:system
        OptionName: SystemType
        Value: enhanced
      - Namespace: aws:autoscaling:launchconfiguration
        OptionName: IamInstanceProfile
        Value: aws-elasticbeanstalk-ec2-role
      - Namespace: aws:autoscaling:launchconfiguration
        OptionName: InstanceType
        Value: !Ref ApplicationInstanceType
      - Namespace: aws:autoscaling:launchconfiguration
        OptionName: EC2KeyName
        Value: !Ref KeyName
      - Namespace: aws:autoscaling:launchconfiguration
        OptionName: SecurityGroups
        Value: !Ref ApplicationSecurityGroup
      - Namespace: aws:elb:loadbalancer
        OptionName: SecurityGroups
        Value: !Ref LoadBalancerSecurityGroup
      - Namespace: aws:elasticbeanstalk:container:nodejs
        OptionName: NodeCommand
        Value: npm start
      - Namespace: aws:elasticbeanstalk:application:environment
        OptionName: REDIS_ADDRESS
        Value: !Sub "redis://${RedisCluster.RedisEndpoint.Address}:${RedisCluster.RedisEndpoint.Port}"
      - Namespace: aws:elasticbeanstalk:container:nodejs
        OptionName: ProxyServer
        Value: nginx
  ChatEnvironment:
    Type: AWS::ElasticBeanstalk::Environment
    Properties:
      ApplicationName: !Ref ChatApplication
      Description: AWS ElasticBeanstalk Chat Environment
      TemplateName: !Ref ChatConfigurationTemplate
      VersionLabel: !Ref ChatApplicationVersion
  ApplicationSecurityGroup:
    Type: AWS::EC2::SecurityGroup
    Properties:
      GroupDescription: Application security group
  ApplicationSecurityGroupIngress:
    Type: AWS::EC2::SecurityGroupIngress
    Properties:
      GroupId: !GetAtt ApplicationSecurityGroup.GroupId
      IpProtocol: tcp
      FromPort: 80
      ToPort: 80
      SourceSecurityGroupId: !GetAtt LoadBalancerSecurityGroup.GroupId
  LoadBalancerSecurityGroup:
    Type: AWS::EC2::SecurityGroup
    Properties:
      GroupDescription: Load balancer security group
  LoadBalancerSecurityGroupIngress:
    Type: AWS::EC2::SecurityGroupIngress
    Properties:
      GroupId: !GetAtt LoadBalancerSecurityGroup.GroupId
      IpProtocol: tcp
      FromPort: 80
      ToPort: 80
      CidrIp: 0.0.0.0/0