Scaling Policy

{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://raw.githubusercontent.com/api-evangelist/scalability/main/json-schema/scalability-scaling-policy-schema.json",
  "title": "Scaling Policy",
  "description": "Defines a scaling policy for automatically adjusting compute resources based on demand, applicable to cloud auto-scaling systems like KEDA, AWS Auto Scaling, Azure Autoscale, and GCP Autoscaler.",
  "type": "object",
  "required": ["name", "targetRef", "triggers"],
  "properties": {
    "name": {
      "type": "string",
      "description": "Unique identifier name for the scaling policy.",
      "minLength": 1,
      "maxLength": 253
    },
    "namespace": {
      "type": "string",
      "description": "Namespace or resource group where the policy applies.",
      "default": "default"
    },
    "targetRef": {
      "type": "object",
      "description": "Reference to the target resource being scaled.",
      "required": ["kind", "name"],
      "properties": {
        "apiVersion": {
          "type": "string",
          "description": "API version of the target resource.",
          "example": "apps/v1"
        },
        "kind": {
          "type": "string",
          "description": "Kind of the target resource.",
          "enum": ["Deployment", "StatefulSet", "ReplicaSet", "DaemonSet", "Job", "CronJob", "Function", "ContainerApp"]
        },
        "name": {
          "type": "string",
          "description": "Name of the target resource."
        }
      }
    },
    "minReplicaCount": {
      "type": "integer",
      "description": "Minimum number of replicas to scale down to. Set to 0 for scale-to-zero.",
      "minimum": 0,
      "default": 0
    },
    "maxReplicaCount": {
      "type": "integer",
      "description": "Maximum number of replicas to scale up to.",
      "minimum": 1,
      "default": 100
    },
    "pollingInterval": {
      "type": "integer",
      "description": "Interval in seconds between polling triggers for scaling decisions.",
      "minimum": 1,
      "default": 30
    },
    "cooldownPeriod": {
      "type": "integer",
      "description": "Seconds to wait after the last active trigger before scaling down.",
      "minimum": 0,
      "default": 300
    },
    "triggers": {
      "type": "array",
      "description": "List of scaling triggers that drive autoscaling decisions.",
      "minItems": 1,
      "items": {
        "$ref": "#/$defs/ScalingTrigger"
      }
    },
    "scalingBehavior": {
      "$ref": "#/$defs/ScalingBehavior"
    },
    "tags": {
      "type": "object",
      "description": "Key-value metadata labels for the scaling policy.",
      "additionalProperties": {
        "type": "string"
      }
    }
  },
  "$defs": {
    "ScalingTrigger": {
      "type": "object",
      "description": "A trigger that drives autoscaling, such as CPU usage, queue depth, or custom metrics.",
      "required": ["type"],
      "properties": {
        "type": {
          "type": "string",
          "description": "Trigger type identifier.",
          "examples": ["cpu", "memory", "kafka", "aws-sqs-queue", "azure-service-bus", "prometheus", "rabbitmq", "redis", "cron"]
        },
        "name": {
          "type": "string",
          "description": "Optional name for this trigger."
        },
        "threshold": {
          "type": "number",
          "description": "Target metric value triggering scale-out.",
          "minimum": 0
        },
        "metadata": {
          "type": "object",
          "description": "Trigger-specific configuration parameters.",
          "additionalProperties": {
            "type": "string"
          }
        },
        "authenticationRef": {
          "type": "object",
          "description": "Reference to a TriggerAuthentication resource.",
          "properties": {
            "name": {
              "type": "string"
            },
            "kind": {
              "type": "string",
              "enum": ["TriggerAuthentication", "ClusterTriggerAuthentication"]
            }
          }
        }
      }
    },
    "ScalingBehavior": {
      "type": "object",
      "description": "Controls how scaling is performed (scale-up and scale-down rates and policies).",
      "properties": {
        "scaleUp": {
          "$ref": "#/$defs/ScalingRules"
        },
        "scaleDown": {
          "$ref": "#/$defs/ScalingRules"
        }
      }
    },
    "ScalingRules": {
      "type": "object",
      "description": "Rules governing the rate and behavior of scaling in one direction.",
      "properties": {
        "stabilizationWindowSeconds": {
          "type": "integer",
          "description": "How long (in seconds) to look back at metrics before making a scaling decision.",
          "minimum": 0,
          "maximum": 3600
        },
        "policies": {
          "type": "array",
          "items": {
            "type": "object",
            "required": ["type", "value", "periodSeconds"],
            "properties": {
              "type": {
                "type": "string",
                "enum": ["Pods", "Percent"]
              },
              "value": {
                "type": "integer",
                "minimum": 1
              },
              "periodSeconds": {
                "type": "integer",
                "minimum": 1
              }
            }
          }
        },
        "selectPolicy": {
          "type": "string",
          "enum": ["Max", "Min", "Disabled"],
          "default": "Max"
        }
      }
    }
  }
}