ACS::ECS::AlarmSpotPriceOrDiscountByScalingGroupInstance.json

{
  "FormatVersion": "OOS-2019-06-01",
  "Description": "Alarm notification when spot instance discount or spot price exceeds threshold in the scaling group existing instances.",
  "Parameters": {
    "regionId": {
      "Description": "The region id.",
      "Type": "String"
    },
    "threshold": {
      "Description": "The discount threshold(example:10 is 1% off, 50 is 50% off).",
      "Type": "Number"
    },
    "taskType": {
      "Description": "Monitoring threshold task type.",
      "Type": "String"
    },
    "instanceType": {
      "Description": "The instance type.",
      "Type": "String"
    },
    "zoneId": {
      "Description": "The zone id.",
      "Type": "String"
    }
  },
  "Tasks": [
    {
      "Name": "describeSpotPriceHistoryInfos",
      "Action": "ACS::ExecuteAPI",
      "Description": "Get the latest discounts on spot instance.",
      "Properties": {
        "Service": "ECS",
        "API": "DescribeSpotPriceHistory",
        "Parameters": {
          "RegionId": "{{ regionId }}",
          "InstanceType": "{{ instanceType }}",
          "NetworkType": "vpc",
          "ZoneId": "{{ zoneId }}"
        }
      },
      "Outputs": {
        "discountAndPrice": {
          "Type": "Json",
          "ValueSelector": ".SpotPrices.SpotPriceType[-1] | {\"realThreshold\":(.SpotPrice / .OriginPrice * 100), \"spotPrice\":.SpotPrice, \"originPrice\":.OriginPrice, \"instanceType\":.InstanceType}"
        }
      }
    },
    {
      "Name": "selectTask",
      "Action": "ACS::Choice",
      "Description": "Select the type of task that performs the monitoring threshold.",
      "Properties": {
        "DefaultTask": "ACS::END",
        "Choices": [
          {
            "When": {
              "Fn::Equals": [
                "Discount",
                "{{ taskType }}"
              ]
            },
            "NextTask": "checkDiscountThreshold"
          },
          {
            "When": {
              "Fn::Equals": [
                "Price",
                "{{ taskType }}"
              ]
            },
            "NextTask": "checkSpotPriceThreshold"
          }
        ]
      }
    },
    {
      "Name": "checkDiscountThreshold",
      "Action": "ACS::Choice",
      "Description": "Check if the actual discount exceeds the threshold.",
      "Properties": {
        "DefaultTask": "ACS::END",
        "Choices": [
          {
            "When": {
              "Fn::Equals": [
                true,
                {
                  "Fn::Jq": [
                    "First",
                    ".realThreshold >= {{ threshold }}",
                    "{{ describeSpotPriceHistoryInfos.discountAndPrice }}"
                  ]
                }
              ]
            },
            "NextTask": "describeSpotPriceHistory"
          }
        ]
      }
    },
    {
      "Name": "checkSpotPriceThreshold",
      "Action": "ACS::Choice",
      "Description": "Check if the actual discount exceeds the threshold.",
      "Properties": {
        "DefaultTask": "ACS::END",
        "Choices": [
          {
            "When": {
              "Fn::Equals": [
                true,
                {
                  "Fn::Jq": [
                    "First",
                    ".spotPrice >= {{ threshold }}",
                    "{{ describeSpotPriceHistoryInfos.discountAndPrice }}"
                  ]
                }
              ]
            },
            "NextTask": "describeSpotPriceHistory"
          }
        ]
      }
    },
    {
      "Name": "describeSpotPriceHistory",
      "Action": "ACS::ExecuteAPI",
      "Description": "Get the latest discounts or spot price on spot instance.",
      "Properties": {
        "Service": "ECS",
        "API": "DescribeSpotPriceHistory",
        "Parameters": {
          "RegionId": "{{ regionId }}",
          "InstanceType": "{{ instanceType }}",
          "NetworkType": "vpc",
          "ZoneId": "{{ zoneId }}"
        }
      },
      "Outputs": {
        "spotPrice": {
          "Type": "String",
          "ValueSelector": ".SpotPrices.SpotPriceType[-1].SpotPrice"
        },
        "instanceType": {
          "Type": "String",
          "ValueSelector": ".SpotPrices.SpotPriceType[-1].InstanceType"
        },
        "zoneId": {
          "Type": "String",
          "ValueSelector": ".SpotPrices.SpotPriceType[-1].ZoneId"
        },
        "actualDiscount": {
          "Type": "String",
          "ValueSelector": ".SpotPrices.SpotPriceType[-1] | .SpotPrice / .OriginPrice * 10000 | floor as $num | $num/100"
        }
      }
    }
  ],
  "Outputs": {
    "discountInfo": {
      "Type": "Json",
      "Value": {
        "instanceType": "{{ describeSpotPriceHistory.instanceType }}",
        "zoneId": "{{ describeSpotPriceHistory.zoneId }}",
        "spotPrice": "{{ describeSpotPriceHistory.spotPrice }}",
        "actualDiscount": "\"{{ describeSpotPriceHistory.actualDiscount }}\""
      }
    }
  }
}