core/homeassistant/components/http/data_validator.py

52 lines
1.5 KiB
Python

"""Decorator for view methods to help with data validation."""
from functools import wraps
import logging
import voluptuous as vol
# mypy: allow-untyped-defs
_LOGGER = logging.getLogger(__name__)
class RequestDataValidator:
"""Decorator that will validate the incoming data.
Takes in a voluptuous schema and adds 'post_data' as
keyword argument to the function call.
Will return a 400 if no JSON provided or doesn't match schema.
"""
def __init__(self, schema, allow_empty=False):
"""Initialize the decorator."""
self._schema = schema
self._allow_empty = allow_empty
def __call__(self, method):
"""Decorate a function."""
@wraps(method)
async def wrapper(view, request, *args, **kwargs):
"""Wrap a request handler with data validation."""
data = None
try:
data = await request.json()
except ValueError:
if not self._allow_empty or (await request.content.read()) != b"":
_LOGGER.error("Invalid JSON received.")
return view.json_message("Invalid JSON.", 400)
data = {}
try:
kwargs["data"] = self._schema(data)
except vol.Invalid as err:
_LOGGER.error("Data does not match schema: %s", err)
return view.json_message(f"Message format incorrect: {err}", 400)
result = await method(view, request, *args, **kwargs)
return result
return wrapper