# 
# This sample adds Amazon CloudWatch alarms to the AWS Elastic Beanstalk Elastic Load Balancer.
#
# To configure the Alarm, you should create a separate configuration file that contains
# an option-settings section such as the following (all properties are showing the default values).
#
#  option_settings:
#   "aws:elasticbeanstalk:customoption":
#     ELBAlarmEmail: "nobody@amazon.com"
#     ELBHealthyHostCount: "1"
#     ELBLatency: "0.5"
#     ELBHTTP5xxErrors: "0"
#
##

Resources:
  ELBAlarmTopic:
    Type: AWS::SNS::Topic
    Properties:
      Subscription:
        - Endpoint:
            Fn::GetOptionSetting:
              OptionName: ELBAlarmEmail
              DefaultValue: "nobody@amazon.com"
          Protocol: email

  ELBHealthyHostCountAlarm:
    Type: AWS::CloudWatch::Alarm
    Properties:
      AlarmDescription: { "Fn::Join" : ["", [{ "Ref" : "AWSEBEnvironmentName" }, ": ELB no healthy backend hosts." ]]}
      Namespace: AWS/ELB
      MetricName: HealthyHostCount
      Dimensions:
        - Name: LoadBalancerName
          Value : { "Ref" : "AWSEBLoadBalancer" }
      Statistic: Average
      Period: 300
      EvaluationPeriods: 1
      Threshold: 
        Fn::GetOptionSetting:
          OptionName: ELBHealthyHostCount
          DefaultValue: "1"
      ComparisonOperator: LessThanThreshold
      AlarmActions:
        - Ref: ELBAlarmTopic
      InsufficientDataActions:
        - Ref: ELBAlarmTopic

  ELBLatencyAlarm:
    Type: AWS::CloudWatch::Alarm
    Properties:
      AlarmDescription: { "Fn::Join" : ["", [{ "Ref" : "AWSEBEnvironmentName" }, ": HIGH ELB latency." ]]}
      Namespace: AWS/ELB
      MetricName: Latency
      Dimensions:
        - Name: LoadBalancerName
          Value : { "Ref" : "AWSEBLoadBalancer" }
      Statistic: Average
      Period: 300
      EvaluationPeriods: 1
      Threshold: 
        Fn::GetOptionSetting:
          OptionName: ELBLatency
          DefaultValue: "0.5"
      ComparisonOperator: GreaterThanThreshold
      AlarmActions:
        - Ref: ELBAlarmTopic
      InsufficientDataActions:
        - Ref: ELBAlarmTopic

  ELBHTTP5xBEAlarm:
    Type: AWS::CloudWatch::Alarm
    Properties:
      AlarmDescription: { "Fn::Join" : ["", [{ "Ref" : "AWSEBEnvironmentName" }, ": HIGH ELB backend HTTP 5xx error rate." ]]}
      Namespace: AWS/ELB
      MetricName: HTTPCode_Backend_5XX
      Dimensions:
        - Name: LoadBalancerName
          Value : { "Ref" : "AWSEBLoadBalancer" }
      Statistic: Sum
      Period: 300
      EvaluationPeriods: 1
      Threshold: 
        Fn::GetOptionSetting:
          OptionName: ELBHTTP5xxErrors
          DefaultValue: "0"
      ComparisonOperator: GreaterThanThreshold
      AlarmActions:
        - Ref: ELBAlarmTopic
      InsufficientDataActions:
        - Ref: ELBAlarmTopic