Deploy CanNotDelete Resource Lock on Resource Groups

EnforceDoNotDeleteLock.json

{
    "properties": {
        "displayName": "Deploy CanNotDelete Resource Lock on Resource Groups",
        "description": "Creates a resource lock at the resource group level for preventing resource deletion.",
        "mode": "all",
        "metadata": {
            "version": "1.0.0",
            "category": "General"
        },
        "parameters": {},
        "policyRule": {
            "if": {
                "field": "type",
                "equals": "Microsoft.Resources/subscriptions/resourceGroups"
            },
            "then": {
                "effect": "DeployIfNotExists",
                "details": {
                    "type": "Microsoft.Authorization/locks",
                    "existenceCondition": {
                        "field": "Microsoft.Authorization/locks/level",
                        "equals": "CanNotDelete"
                    },
                    "roleDefinitionIds": [
                        "/providers/Microsoft.Authorization/roleDefinitions/8e3af657-a8ff-443c-a75c-2fe8c4bcb635"
                    ],
                    "deployment": {
                        "properties": {
                            "mode": "incremental",
                            "template": {
                                "$schema": "https://schema.management.azure.com/schemas/2015-01-01/deploymentTemplate.json",
                                "contentVersion": "1.0.0.0",
                                "resources": [
                                    {
                                        "type": "Microsoft.Authorization/locks",
                                        "apiVersion": "2017-04-01",
                                        "name": "DenyDelete",
                                        "properties": {
                                            "level": "CanNotDelete",
                                            "notes": "Prevents deletion of resource group."
                                        }
                                    }
                                ]
                            }
                        }
                    }
                }
            }
        }
    }
}