zookeeper.json

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

  "Description" : "Launches an Exhibitor-managed ZooKeeper cluster",

  "Parameters" : {
    "InstanceType" : {
      "Description" : "EC2 instance type",
      "Type" : "String",
      "Default" : "t2.micro",
      "AllowedValues" : [
        "t2.micro", "t2.small", "t2.medium",
        "m3.medium", "m3.large", "m3.xlarge", "m3.2xlarge",
        "c3.large", "c3.xlarge", "c3.2xlarge", "c3.4xlarge", "c3.8xlarge",
        "c4.large", "c4.xlarge", "c4.2xlarge", "c4.4xlarge", "c4.8xlarge",
        "r3.large", "r3.xlarge", "r3.2xlarge", "r3.4xlarge", "r3.8xlarge",
        "i2.xlarge", "i2.2xlarge", "i2.4xlarge", "i2.8xlarge",
        "hs1.8xlarge", "g2.2xlarge"
      ],
      "ConstraintDescription" : "must be a valid, HVM-compatible EC2 instance type."
    },
    "KeyName" : {
      "Description" : "Existing EC2 KeyPair to be associated with all cluster instances for SSH access. For default AMIs, log in as the 'ubuntu' user.",
      "Type" : "AWS::EC2::KeyPair::KeyName"
    },
    "ClusterSize" : {
      "Description" : "Number of nodes to launch",
      "Type" : "Number",
      "Default": 3
    },
    "DockerImage" : {
      "Description" : "Path of the ZK+Exhibitor Docker image (format: '[<registry>[:<port>]/]<repository>:<version>')",
      "Type" : "String",
      "Default" : "mbabineau/zookeeper-exhibitor:3.4.6_1.5.4"
    },
    "ExhibitorS3Bucket" : {
      "Description" : "Bucket for Exhibitor backups of ZK configs",
      "Type" : "String"
    },
    "ExhibitorS3Region" : {
      "Description" : "Region for Exhibitor backups of ZK configs",
      "Type" : "String"
    },
    "ExhibitorS3Prefix" : {
      "Description" : "Key prefix for S3 backups. Should be unique per S3 bucket per cluster",
      "Type" : "String"
    },
    "Subnets" : {
      "Description" : "List of VPC subnet IDs for the cluster. Note: must match up with the passed AvailabilityZones.",
      "Type" : "List<AWS::EC2::Subnet::Id>"
    },
    "VpcId" : {
      "Description" : "VPC associated with the provided subnets",
      "Type" : "AWS::EC2::VPC::Id"
    },
    "AdminSecurityGroup" : {
      "Description" : "Existing security group that should be granted administrative access to ZooKeeper (e.g., 'sg-123456')",
      "Type" : "AWS::EC2::SecurityGroup::Id"
    },
    "AvailabilityZones": {
      "Description" : "(Optional) If passed, only launch nodes in these AZs (e.g., 'us-east-1a,us-east-1b'). Note: these must match up with the passed Subnets.",
      "Type" : "CommaDelimitedList",
      "Default" : ""
    }
  },

  "Mappings" : {
    "RegionMap" : {
      "us-east-1" : {
        "AMI" : "ami-87705d90"
      },
      "us-west-1" : {
        "AMI" : "ami-1b1e4b7b"
      },
      "us-west-2" : {
        "AMI" : "ami-70b71410"
      },
      "eu-west-1" : {
        "AMI" : "ami-fb91c788"
      },
      "ap-southeast-1" : {
        "AMI" : "ami-c7e447a4"
      },
      "ap-southeast-2" : {
        "AMI" : "ami-ac3a05cf"
      },
      "ap-northeast-1" : {
        "AMI" : "ami-6dc0690c"
      },
      "sa-east-1" : {
        "AMI" : "ami-45ff6029"
      }
    }
  },

  "Conditions" : {
    "UseAllAvailabilityZones" : {"Fn::Equals" : [{ "Fn::Join" : ["", {"Ref" : "AvailabilityZones"} ]}, ""]}
  },

  "Resources" : {
    "IAMUser" : {
      "Type" : "AWS::IAM::User",
      "Properties" : {
        "Policies" : [{
          "PolicyName" : "S3Access",
          "PolicyDocument" : {
            "Statement": [{
              "Effect"   : "Allow",
              "Action"   : "s3:*",
              "Resource" : { "Fn::Join" : ["", ["arn:aws:s3:::", {"Ref" : "ExhibitorS3Bucket"} , "/*"]]}
            }]
          }
        },
        {
          "PolicyName" : "IAMAccess",
          "PolicyDocument" : {
            "Statement" : [{
              "Effect"    : "Allow",
              "NotAction" : "iam:*",
              "Resource"  : "*"
            }]
          }
        }]
      }
    },

    "HostKeys" : {
      "Type" : "AWS::IAM::AccessKey",
      "Properties" : {
        "UserName" : {"Ref": "IAMUser"}
      }
    },

    "ServerGroup" : {
      "Type" : "AWS::AutoScaling::AutoScalingGroup",
      "Properties" : {
        "AvailabilityZones" : {
          "Fn::If" : [
            "UseAllAvailabilityZones",
            { "Fn::GetAZs": "AWS::Region" },
            { "Ref" : "AvailabilityZones" }
          ]
        },
        "LaunchConfigurationName" : { "Ref" : "LaunchConfig" },
        "MinSize" : "1",
        "MaxSize" : "9",
        "DesiredCapacity" : { "Ref" : "ClusterSize" },
        "LoadBalancerNames" : [ { "Ref" : "ElasticLoadBalancer" } ],
        "VPCZoneIdentifier" : { "Ref" : "Subnets" },
        "Tags" : [
          {
            "Key" : "role",
            "Value" : "zookeeper",
            "PropagateAtLaunch" : "true"
          }
        ]
      }
    },

    "LaunchConfig" : {
      "Type" : "AWS::AutoScaling::LaunchConfiguration",
      "Properties" : {
        "KeyName" : { "Ref" : "KeyName" },
        "ImageId" : { "Fn::FindInMap" : [ "RegionMap", { "Ref" : "AWS::Region" }, "AMI"] },
        "SecurityGroups" : [ { "Ref" : "ServerSecurityGroup" }, { "Ref" : "AdminSecurityGroup" }  ],
        "AssociatePublicIpAddress": "true",
        "InstanceType" : { "Ref" : "InstanceType" },
        "UserData"       : { "Fn::Base64" : { "Fn::Join" : ["", [
          "#!/bin/bash -ex\n",

          "# Helper function\n",
          "function error_exit\n",
          "{\n",
          "  cfn-signal -e 1 -r \"$1\" '", { "Ref" : "WaitHandle" }, "'\n",
          "  exit 1\n",
          "}\n",

          "# Set up and start the Exhibitor+ZooKeeper service\n",
          "docker pull ", { "Ref": "DockerImage" }, "\n",
          "runit-service create zk docker run ",
          "   -p 8181:8181 -p 2181:2181 -p 2888:2888 -p 3888:3888",
          "   -e 'S3_BUCKET=", { "Ref" : "ExhibitorS3Bucket" }, "'",
          "   -e 'S3_PREFIX=", { "Ref" : "ExhibitorS3Prefix" }, "'",
          "   -e 'AWS_ACCESS_KEY_ID=", { "Ref" : "HostKeys" }, "'",
          "   -e 'AWS_SECRET_ACCESS_KEY=", {"Fn::GetAtt": ["HostKeys", "SecretAccessKey"]}, "'",
          "   -e 'AWS_REGION=", { "Ref" : "ExhibitorS3Region" }, "'",
          "   -e \"HOSTNAME=`ec2metadata --public-hostname`\"",
          "   ", { "Ref": "DockerImage" }, "\n",
          "runit-service enable zk\n",

          "# All is well so signal success\n",
          "cfn-signal -e 0 -r \"Stack setup complete\" '", { "Ref" : "WaitHandle" }, "'\n",

          "#EOF"
        ]]}}
      }
    },

    "ClientSecurityGroup" : {
      "Type" : "AWS::EC2::SecurityGroup",
      "Properties" : {
        "GroupDescription" : "For ZooKeeper clients. Grants access to the associated ZooKeeper cluster.",
        "VpcId" : { "Ref" : "VpcId" }
      }
    },

    "ServerSecurityGroup" : {
      "Type" : "AWS::EC2::SecurityGroup",
      "Properties" : {
        "GroupDescription" : "Enable SSH and Exhibitor access",
        "VpcId" : { "Ref" : "VpcId" },
        "SecurityGroupIngress" :
          [ { "IpProtocol" : "tcp", "FromPort" : "8181", "ToPort" : "8181", "SourceSecurityGroupId" : { "Ref" : "LbSecurityGroup"} },
            { "IpProtocol" : "tcp", "FromPort" : "2181", "ToPort" : "2181", "SourceSecurityGroupId" : { "Ref" : "ClientSecurityGroup"} },
            { "IpProtocol" : "tcp", "FromPort" : "2888", "ToPort" : "2888", "SourceSecurityGroupId" : { "Ref" : "ClientSecurityGroup"} },
            { "IpProtocol" : "tcp", "FromPort" : "3888", "ToPort" : "3888", "SourceSecurityGroupId" : { "Ref" : "ClientSecurityGroup"} } ]
      }
    },

    "SecurityGroupIngress": {
      "Type": "AWS::EC2::SecurityGroupIngress",
      "Properties": {
        "GroupId": { "Ref": "ServerSecurityGroup" },
        "IpProtocol": "-1",
        "FromPort": "0",
        "ToPort": "65535",
        "SourceSecurityGroupId": { "Ref": "ServerSecurityGroup" }
      }
    },

    "LbSecurityGroup" : {
      "Type" : "AWS::EC2::SecurityGroup",
      "Properties" : {
        "GroupDescription" : "Enable Exhibitor access",
        "VpcId" : { "Ref" : "VpcId" },
        "SecurityGroupIngress" :
          [ { "IpProtocol" : "tcp", "FromPort" : "80", "ToPort" : "80", "SourceSecurityGroupId" : { "Ref" : "ClientSecurityGroup"} } ]
      }
    },

    "ElasticLoadBalancer" : {
      "Type" : "AWS::ElasticLoadBalancing::LoadBalancer",
      "Properties" : {
        "CrossZone": "true",
        "Scheme": "internal",
        "SecurityGroups": [{ "Ref": "LbSecurityGroup" }, { "Ref": "AdminSecurityGroup" }],
        "Subnets": { "Ref": "Subnets" },
        "Listeners" : [ {
          "LoadBalancerPort" : "80",
          "InstancePort" : "8181",
          "Protocol" : "HTTP"
        } ],
        "HealthCheck" : {
          "Target" : "HTTP:8181/exhibitor/v1/cluster/state",
          "HealthyThreshold" : "3",
          "UnhealthyThreshold" : "5",
          "Interval" : "30",
          "Timeout" : "5"
        }
      }
    },

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

  "Outputs" : {
    "ExhibitorDiscoveryUrl" : {
      "Value" : { "Fn::Join" : ["", [
        "http://", { "Fn::GetAtt" : [ "ElasticLoadBalancer", "DNSName" ]}, "/exhibitor/v1/cluster/list"
      ]]}
    },
    "ClientSecurityGroup" : {
      "Value" : { "Ref" : "ClientSecurityGroup" }
    }
  }
}