@Description 'Simplified Rails instance with an RDS.'

@Param.String 'KeyName',            'Name of an existing EC2 KeyPair to enable SSH access to the instances'
@Param.String 'DBName',             'MySQL database name', Default: 'MyDatabase'
@Param.String 'DBUsername',         'Username for MySQL database access', NoEcho: 'true'
@Param.String 'DBPassword',         'Password for MySQL database access', NoEcho: 'true'
@Param.Number 'DBAllocatedStorage', 'The size of the database (Gb)', Default: '5'
@Param.String 'DBInstanceClass',    'The database instance type', Default: 'db.m1.small'
@Param.String 'InstanceType',       'WebServer EC2 instance type', Default: 'm1.small'

@Mapping 'AWSInstanceType2Arch',
  't1.micro'    : { 'Arch' : '32' },
  'm1.small'    : { 'Arch' : '32' },
  'm1.large'    : { 'Arch' : '64' },
  'm1.xlarge'   : { 'Arch' : '64' },
  'm2.xlarge'   : { 'Arch' : '64' },
  'm2.2xlarge'  : { 'Arch' : '64' },
  'm2.4xlarge'  : { 'Arch' : '64' },
  'c1.medium'   : { 'Arch' : '32' },
  'c1.xlarge'   : { 'Arch' : '64' },
  'cc1.4xlarge' : { 'Arch' : '64' }

@Mapping 'AWSRegionArch2AMI',
  'us-east-1'      : { '32' : 'ami-7f418316', '64' : 'ami-7341831a' },
  'us-west-1'      : { '32' : 'ami-951945d0', '64' : 'ami-971945d2' },
  'us-west-2'      : { '32' : 'ami-16fd7026', '64' : 'ami-10fd7020' },
  'eu-west-1'      : { '32' : 'ami-24506250', '64' : 'ami-20506254' },
  'ap-southeast-1' : { '32' : 'ami-74dda626', '64' : 'ami-7edda62c' },
  'ap-northeast-1' : { '32' : 'ami-dcfa4edd', '64' : 'ami-e8fa4ee9' }

@AWS.IAM.User 'CfnUser',
  Path: '/'
  Policies: [
    PolicyName: 'root'
    PolicyDocument:
      Statement: [
        Effect:'Allow'
        Action:'cloudformation:DescribeStackResource'
        Resource:'*'
      ]
    ]
@AWS.IAM.AccessKey 'HostKeys',
  UserName: @Resources.CfnUser

openPort = (port) ->
  IpProtocol: 'tcp'
  FromPort:   port
  ToPort:     port
  CidrIp:     '0.0.0.0/0'
@AWS.EC2.SecurityGroup 'WebServerSecurityGroup',
  GroupDescription: 'Enable HTTP access via port 3000 plus SSH access'
  SecurityGroupIngress: [
    openPort '3000',
    openPort '22'
  ]
@AWS.RDS.DBSecurityGroup 'DBSecurityGroup',
  GroupDescription: 'Grant database access to web server'
  DBSecurityGroupIngress:
    EC2SecurityGroupName: @Resources.WebServerSecurityGroup

@AWS.EC2.Instance 'WebServer',
  Metadata:
    Comment1: 'Configure the bootstrap helpers to install the Rails'
    Comment2: 'The application is downloaded from the CloudFormationRailsSample.zip file'
    'AWS::CloudFormation::Init':
      config:
        packages:
          yum:
            'gcc-c++'      : []
            'make'         : []
            'ruby-devel'   : []
            'rubygems'     : []
            'mysql'        : []
            'mysql-devel'  : []
            'mysql-libs'   : []

          rubygems:
            'execjs'       : []
            'therubyracer' : []
            'rails'        : []
        sources: '/home/ec2-user/sample' : 'https://s3.amazonaws.com/cloudformation-examples/CloudFormationRailsSample.zip'
  ###
        files:
          '/home/ec2-user/sample/config/database.yml':
            content: @Join '', [
              '''development:
                adapter: mysql2
                encoding: utf8
                reconnect: false
                pool: 5
                database: ''', @Params.DBName, "\n",
                "username: ", @Params.DBUsername, "\n",
                "password: ", @Params.DBPassword, "\n",
                "host: ", @GetAtt('MySQLDatabase', 'Endpoint.Address'), "\n",
                "port: ", @GetAtt('MySQLDatabase', 'Endpoint.Port'), "\n"
            ]
            mode: '000644'
            owner: 'root'
            group: 'root'
    ImageId: @FindInMap('AWSRegionArch2AMI', Ref: @Region, @FindInMap('AWSInstanceType2Arch', @Params.InstanceType, 'Arch'))
  Properties:
    InstanceType: @Params.InstanceType
    SecurityGroups: [ @Resources.WebServerSecurityGroup ]
    KeyName: @Params.KeyName
    UserData: @Base64 @Join '', '''#!/bin/bash -v
      yum update -y aws-cfn-bootstrap
      # Helper function
      function error_exit
      {
        /opt/aws/bin/cfn-signal -e 1 -r \"$1\" '", @Resources.WaitHandle, "'
        exit 1
      }
      # Install Rails packages
      /opt/aws/bin/cfn-init -s ", Ref: @StackName, " -r WebServer --access-key ",  @Params.HostKeys,
      "--secret-key ''', @GetAtt('HostKeys', 'SecretAccessKey'), " --region ", Ref: @Region, " || error_exit 'Failed to run cfn-init'

      # Install anu other Gems, create the database and run a migration
      cd /home/ec2-user/sample
      bundle install  || error_exit 'Failed to install bundle'
      rake db:migrate || error_exit 'Failed to execute database migration'

      # Startup the rails server
      rails server -d
      echo \"cd /home/ec2-user/sample\" >> /etc/rc.local
      echo \"rails server -d\" >> /etc/rc.local

      # All is well so signal success
      /opt/aws/bin/cfn-signal -e 0 -r \"Rails application setup complete\" '", @Resources.WaitHandle, "'\n"

  ###