{
  "properties": {
    "displayName": "Authentication should be enabled on your Function app",
    "policyType": "BuiltIn",
    "mode": "Indexed",
    "description": "Azure App Service Authentication is a feature that can prevent anonymous HTTP requests from reaching the Function app, or authenticate those that have tokens before they reach the Function app",
    "metadata": {
      "version": "1.0.0",
      "category": "App Service"
    },
    "parameters": {
      "effect": {
        "type": "string",
        "defaultValue": "AuditIfNotExists",
        "allowedValues": [
          "AuditIfNotExists",
          "Disabled"
        ],
        "metadata": {
          "displayName": "Effect",
          "description": "Enable or disable the execution of the policy"
        }
      }
    },
    "policyRule": {
      "if": {
        "allOf": [
          {
            "field": "type",
            "equals": "Microsoft.Web/sites"
          },
          {
            "field": "kind",
            "equals": "functionapp"
          }
        ]
      },
      "then": {
        "effect": "[parameters('effect')]",
        "details": {
          "type": "Microsoft.Web/sites/config",
          "name": "web",
          "existenceCondition": {
            "field": "Microsoft.Web/sites/config/siteAuthEnabled",
            "equals": "true"
          }
        }
      }
    }
  },
  "id": "/providers/Microsoft.Authorization/policyDefinitions/c75248c1-ea1d-4a9c-8fc9-29a6aabd5da8",
  "name": "c75248c1-ea1d-4a9c-8fc9-29a6aabd5da8"
}