Add a service require_admin wrapper (#21953)

* Add a service require_admin wrapper

* Allow it to be used as a decorator

* Lint

* Add comment

* Add docstring

* Update syntax

homeassistant/helpers/service.py

@@ -1,7 +1,9 @@
 """Service calling related helpers."""
 import asyncio
+from functools import wraps
 import logging
 from os import path
+from typing import Callable
 
 import voluptuous as vol
 
@@ -10,7 +12,7 @@ from homeassistant.const import (
     ATTR_ENTITY_ID, ENTITY_MATCH_ALL, ATTR_AREA_ID)
 import homeassistant.core as ha
 from homeassistant.exceptions import TemplateError, Unauthorized, UnknownUser
-from homeassistant.helpers import template
+from homeassistant.helpers import template, typing
 from homeassistant.loader import get_component, bind_hass
 from homeassistant.util.yaml import load_yaml
 import homeassistant.helpers.config_validation as cv
@@ -335,3 +337,25 @@ async def _handle_service_platform_call(func, data, entities, context):
         assert not pending
         for future in done:
             future.result()  # pop exception if have
+
+
+@bind_hass
+@ha.callback
+def async_register_admin_service(hass: typing.HomeAssistantType, domain: str,
+                                 service: str, service_func: Callable,
+                                 schema: vol.Schema) -> None:
+    """Register a service that requires admin access."""
+    @wraps(service_func)
+    async def admin_handler(call):
+        if call.context.user_id:
+            user = await hass.auth.async_get_user(call.context.user_id)
+            if user is None:
+                raise UnknownUser(context=call.context)
+            if not user.is_admin:
+                raise Unauthorized(context=call.context)
+
+        await hass.async_add_job(service_func, call)
+
+    hass.services.async_register(
+        domain, service, admin_handler, schema
+    )