heat/templates/WordPress_Single_Instance_With_HA.template

{
  "AWSTemplateFormatVersion" : "2010-09-09",

  "Description" : "AWS CloudFormation Sample Template WordPress_Multi_Instance: WordPress is web software you can use to create a beautiful website or blog. This template installs two instances: one running a WordPress deployment and the other using a local MySQL database to store the data.",

  "Parameters" : {

    "KeyName" : {
      "Description" : "Name of an existing EC2 KeyPair to enable SSH access to the instances",
      "Type" : "String"
    },

    "InstanceType" : {
      "Description" : "WebServer EC2 instance type",
      "Type" : "String",
      "Default" : "m1.large",
      "AllowedValues" : [ "t1.micro", "m1.small", "m1.large", "m1.xlarge", "m2.xlarge", "m2.2xlarge", "m2.4xlarge", "c1.medium", "c1.xlarge", "cc1.4xlarge" ],
      "ConstraintDescription" : "must be a valid EC2 instance type."
    },

    "DBName": {
      "Default": "wordpress",
      "Description" : "The WordPress database name",
      "Type": "String",
      "MinLength": "1",
      "MaxLength": "64",
      "AllowedPattern" : "[a-zA-Z][a-zA-Z0-9]*",
      "ConstraintDescription" : "must begin with a letter and contain only alphanumeric characters."
    },

    "DBUsername": {
      "Default": "admin",
      "NoEcho": "true",
      "Description" : "The WordPress database admin account username",
      "Type": "String",
      "MinLength": "1",
      "MaxLength": "16",
      "AllowedPattern" : "[a-zA-Z][a-zA-Z0-9]*",
      "ConstraintDescription" : "must begin with a letter and contain only alphanumeric characters."
    },

    "DBPassword": {
      "Default": "admin",
      "NoEcho": "true",
      "Description" : "The WordPress database admin account password",
      "Type": "String",
      "MinLength": "1",
      "MaxLength": "41",
      "AllowedPattern" : "[a-zA-Z0-9]*",
      "ConstraintDescription" : "must contain only alphanumeric characters."
    },

    "DBRootPassword": {
      "Default": "admin",
      "NoEcho": "true",
      "Description" : "Root password for MySQL",
      "Type": "String",
      "MinLength": "1",
      "MaxLength": "41",
      "AllowedPattern" : "[a-zA-Z0-9]*",
      "ConstraintDescription" : "must contain only alphanumeric characters."
    },
    "LinuxDistribution": {
      "Default": "F16",
      "Description" : "Distribution of choice",
      "Type": "String",
      "AllowedValues" : [ "F16", "F17", "U10", "RHEL-6.1", "RHEL-6.2", "RHEL-6.3" ]
    },
    "HupPollInterval": {
      "Default": "1",
      "Description" : "Interval for cfn-hup",
      "Type": "String"
    }
  },

  "Mappings" : {
    "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" }
    },
    "DistroArch2AMI": {
      "F16"      : { "32" : "F16-i386-cfntools", "64" : "F16-x86_64-cfntools" },
      "F17"      : { "32" : "F17-i386-cfntools", "64" : "F17-x86_64-cfntools" },
      "U10"      : { "32" : "U10-i386-cfntools", "64" : "U10-x86_64-cfntools" },
      "RHEL-6.1" : { "32" : "rhel61-i386-cfntools", "64" : "rhel61-x86_64-cfntools" },
      "RHEL-6.2" : { "32" : "rhel62-i386-cfntools", "64" : "rhel62-x86_64-cfntools" },
      "RHEL-6.3" : { "32" : "rhel63-i386-cfntools", "64" : "rhel63-x86_64-cfntools" }
    }
  },

  "Resources" : {
    "CfnUser" : {
      "Type" : "AWS::IAM::User"
    },
    "WebServerKeys" : {
      "Type" : "AWS::IAM::AccessKey",
      "Properties" : {
        "UserName" : {"Ref": "CfnUser"}
      }
    },
    "WebServerRestartPolicy" : {
      "Type" : "HEAT::HA::Restarter",
      "Properties" : {
        "InstanceId" : { "Ref" : "WikiDatabase" }
      }
    },
    "HttpFailureAlarm": {
     "Type": "AWS::CloudWatch::Alarm",
     "Properties": {
        "AlarmDescription": "Restart the WikiDatabase if httpd fails > 3 times in 10 minutes",
        "MetricName": "ServiceFailure",
        "Namespace": "system/linux",
        "Statistic": "SampleCount",
        "Period": "300",
        "EvaluationPeriods": "1",
        "Threshold": "2",
        "AlarmActions": [ { "Ref": "WebServerRestartPolicy" } ],
        "ComparisonOperator": "GreaterThanThreshold"
      }
    },
    "WikiDatabase": {
      "Type": "AWS::EC2::Instance",
      "Metadata" : {
        "AWS::CloudFormation::Init" : {
          "config" : {
            "files" : {
              "/etc/cfn/cfn-credentials" : {
                "content" : { "Fn::Join" : ["", [
                  "AWSAccessKeyId=", { "Ref" : "WebServerKeys" }, "\n",
                  "AWSSecretKey=", {"Fn::GetAtt": ["WebServerKeys",
                                    "SecretAccessKey"]}, "\n"
                ]]},
                "mode"    : "000400",
                "owner"   : "root",
                "group"   : "root"
              },

              "/etc/cfn/cfn-hup.conf" : {
                "content" : { "Fn::Join" : ["", [
                  "[main]\n",
                  "stack=", { "Ref" : "AWS::StackName" }, "\n",
                  "credential-file=/etc/cfn/cfn-credentials\n",
                  "region=", { "Ref" : "AWS::Region" }, "\n",
                  "interval=", { "Ref" : "HupPollInterval" }, "\n"
                ]]},
                "mode"    : "000400",
                "owner"   : "root",
                "group"   : "root"
              },

              "/etc/cfn/notify-on-httpd-restarted" : {
                "content" : { "Fn::Join" : ["", [
                "#!/bin/sh\n",
                "/opt/aws/bin/cfn-push-stats --watch ",
                { "Ref" : "HttpFailureAlarm" },
                " --service-failure\n"
                ]]},
                "mode"    : "000700",
                "owner"   : "root",
                "group"   : "root"
              },

              "/tmp/cfn-hup-crontab.txt" : {
                "content" : { "Fn::Join" : ["", [
                "MAIL=\"\"\n",
                "\n",
                "* * * * * /opt/aws/bin/cfn-hup -f\n"
                ]]},
                "mode"    : "000600",
                "owner"   : "root",
                "group"   : "root"
              },

              "/tmp/setup.mysql" : {
                "content" : { "Fn::Join" : ["", [
                "CREATE DATABASE ", { "Ref" : "DBName" }, ";\n",
                "GRANT ALL PRIVILEGES ON ", { "Ref" : "DBName" },
                ".* TO '", { "Ref" : "DBUsername" }, "'@'localhost'\n",
                "IDENTIFIED BY '", { "Ref" : "DBPassword" }, "';\n",
                "FLUSH PRIVILEGES;\n",
                "EXIT\n"
                  ]]},
                "mode"  : "000644",
                "owner" : "root",
                "group" : "root"
              },

              "/etc/cfn/hooks.conf" : {
                "content": { "Fn::Join" : ["", [
                  "[cfn-http-restarted]\n",
                  "triggers=service.restarted\n",
                  "path=Resources.WikiDatabase.Metadata\n",
                  "action=/etc/cfn/notify-on-httpd-restarted\n",
                  "runas=root\n"
                ]]},
                "mode"    : "000400",
                "owner"   : "root",
                "group"   : "root"
              }
            },
            "packages" : {
              "yum" : {
                "cronie"       : [],
                "mysql"        : [],
                "mysql-server" : [],
                "httpd"        : [],
                "wordpress"    : []
              }
            },
            "services" : {
              "systemd" : {
                "mysqld"   : { "enabled" : "true", "ensureRunning" : "true" },
                "httpd"    : { "enabled" : "true", "ensureRunning" : "true" },
                "crond"    : { "enabled" : "true", "ensureRunning" : "true" }
              }
            }
          }
        }
      },
      "Properties": {
        "ImageId" : { "Fn::FindInMap" : [ "DistroArch2AMI", { "Ref" : "LinuxDistribution" },
                          { "Fn::FindInMap" : [ "AWSInstanceType2Arch", { "Ref" : "InstanceType" }, "Arch" ] } ] },
        "InstanceType"   : { "Ref" : "InstanceType" },
        "KeyName"        : { "Ref" : "KeyName" },
        "UserData"       : { "Fn::Base64" : { "Fn::Join" : ["", [
          "#!/bin/bash -v\n",
          "# Helper function\n",
          "function error_exit\n",
          "{\n",
          "  /opt/aws/bin/cfn-signal -e 1 -r \"$1\" '", { "Ref" : "WaitHandle" }, "'\n",
          "  exit 1\n",
          "}\n",

          "/opt/aws/bin/cfn-init -s ", { "Ref" : "AWS::StackName" },
          " -r WikiDatabase ",
          " --access-key ", { "Ref" : "WebServerKeys" },
          " --secret-key ", {"Fn::GetAtt": ["WebServerKeys", "SecretAccessKey"]},
          " --region ", { "Ref" : "AWS::Region" },
          " || error_exit 'Failed to run cfn-init'\n",

          "# Setup MySQL root password and create a user\n",
          "mysqladmin -u root password '", { "Ref" : "DBRootPassword" },
          "' || error_exit 'Failed to initialize root password'\n",

          "mysql -u root --password='", { "Ref" : "DBRootPassword" },
          "' < /tmp/setup.mysql || error_exit 'Failed to create database.'\n",

          "sed --in-place --e s/database_name_here/", { "Ref" : "DBName" },
          "/ --e s/username_here/", { "Ref" : "DBUsername" },
          "/ --e s/password_here/", { "Ref" : "DBPassword" },
          "/ /usr/share/wordpress/wp-config.php\n",

          "# install cfn-hup crontab\n",
          "crontab /tmp/cfn-hup-crontab.txt\n",

          "# All is well so signal success\n",
          "/opt/aws/bin/cfn-signal -e 0 -r \"Wiki server setup complete\" '",
          { "Ref" : "WaitHandle" }, "'\n"
        ]]}}
      }
    },

    "WaitHandle" : {
      "Type" : "AWS::CloudFormation::WaitConditionHandle"
    },

    "WaitCondition" : {
      "Type" : "AWS::CloudFormation::WaitCondition",
      "DependsOn" : "WikiDatabase",
      "Properties" : {
        "Handle" : {"Ref" : "WaitHandle"},
        "Timeout" : "300"
      }
    }
  },

  "Outputs" : {
    "WebsiteURL" : {
      "Value" : { "Fn::Join" : ["", ["http://", { "Fn::GetAtt" : [ "WikiDatabase", "PublicIp" ]}, "/wordpress"]] },
      "Description" : "URL for Wordpress wiki"
    }
  }
}