core/homeassistant/helpers/json.py

284 lines
8.6 KiB
Python

"""Helpers to help with encoding Home Assistant objects in JSON."""
from collections import deque
from collections.abc import Callable
import datetime
from functools import partial
import json
import logging
from pathlib import Path
from typing import TYPE_CHECKING, Any, Final
import orjson
from homeassistant.util.file import write_utf8_file, write_utf8_file_atomic
from homeassistant.util.json import ( # noqa: F401
JSON_DECODE_EXCEPTIONS as _JSON_DECODE_EXCEPTIONS,
JSON_ENCODE_EXCEPTIONS as _JSON_ENCODE_EXCEPTIONS,
SerializationError,
format_unserializable_data,
json_loads as _json_loads,
)
from .deprecation import (
DeprecatedConstant,
all_with_deprecated_constants,
check_if_deprecated_constant,
deprecated_function,
dir_with_deprecated_constants,
)
_DEPRECATED_JSON_DECODE_EXCEPTIONS = DeprecatedConstant(
_JSON_DECODE_EXCEPTIONS, "homeassistant.util.json.JSON_DECODE_EXCEPTIONS", "2025.8"
)
_DEPRECATED_JSON_ENCODE_EXCEPTIONS = DeprecatedConstant(
_JSON_ENCODE_EXCEPTIONS, "homeassistant.util.json.JSON_ENCODE_EXCEPTIONS", "2025.8"
)
json_loads = deprecated_function(
"homeassistant.util.json.json_loads", breaks_in_ha_version="2025.8"
)(_json_loads)
# These can be removed if no deprecated constant are in this module anymore
__getattr__ = partial(check_if_deprecated_constant, module_globals=globals())
__dir__ = partial(
dir_with_deprecated_constants, module_globals_keys=[*globals().keys()]
)
__all__ = all_with_deprecated_constants(globals())
_LOGGER = logging.getLogger(__name__)
class JSONEncoder(json.JSONEncoder):
"""JSONEncoder that supports Home Assistant objects."""
def default(self, o: Any) -> Any:
"""Convert Home Assistant objects.
Hand other objects to the original method.
"""
if isinstance(o, datetime.datetime):
return o.isoformat()
if isinstance(o, set):
return list(o)
if hasattr(o, "as_dict"):
return o.as_dict()
return json.JSONEncoder.default(self, o)
def json_encoder_default(obj: Any) -> Any:
"""Convert Home Assistant objects.
Hand other objects to the original method.
"""
if hasattr(obj, "json_fragment"):
return obj.json_fragment
if isinstance(obj, (set, tuple)):
return list(obj)
if isinstance(obj, float):
return float(obj)
if hasattr(obj, "as_dict"):
return obj.as_dict()
if isinstance(obj, Path):
return obj.as_posix()
if isinstance(obj, datetime.datetime):
return obj.isoformat()
raise TypeError
if TYPE_CHECKING:
def json_bytes(obj: Any) -> bytes:
"""Dump json bytes."""
else:
json_bytes = partial(
orjson.dumps, option=orjson.OPT_NON_STR_KEYS, default=json_encoder_default
)
"""Dump json bytes."""
class ExtendedJSONEncoder(JSONEncoder):
"""JSONEncoder that supports Home Assistant objects and falls back to repr(o)."""
def default(self, o: Any) -> Any:
"""Convert certain objects.
Fall back to repr(o).
"""
if isinstance(o, datetime.timedelta):
return {"__type": str(type(o)), "total_seconds": o.total_seconds()}
if isinstance(o, datetime.datetime):
return o.isoformat()
if isinstance(o, (datetime.date, datetime.time)):
return {"__type": str(type(o)), "isoformat": o.isoformat()}
try:
return super().default(o)
except TypeError:
return {"__type": str(type(o)), "repr": repr(o)}
def _strip_null(obj: Any) -> Any:
"""Strip NUL from an object."""
if isinstance(obj, str):
return obj.split("\0", 1)[0]
if isinstance(obj, dict):
return {key: _strip_null(o) for key, o in obj.items()}
if isinstance(obj, list):
return [_strip_null(o) for o in obj]
return obj
def json_bytes_strip_null(data: Any) -> bytes:
"""Dump json bytes after terminating strings at the first NUL."""
# We expect null-characters to be very rare, hence try encoding first and look
# for an escaped null-character in the output.
result = json_bytes(data)
if b"\\u0000" not in result:
return result
# We work on the processed result so we don't need to worry about
# Home Assistant extensions which allows encoding sets, tuples, etc.
return json_bytes(_strip_null(orjson.loads(result)))
json_fragment = orjson.Fragment
def json_dumps(data: Any) -> str:
r"""Dump json string.
orjson supports serializing dataclasses natively which
eliminates the need to implement as_dict in many places
when the data is already in a dataclass. This works
well as long as all the data in the dataclass can also
be serialized.
If it turns out to be a problem we can disable this
with option \|= orjson.OPT_PASSTHROUGH_DATACLASS and it
will fallback to as_dict
"""
return json_bytes(data).decode("utf-8")
json_bytes_sorted = partial(
orjson.dumps,
option=orjson.OPT_NON_STR_KEYS | orjson.OPT_SORT_KEYS,
default=json_encoder_default,
)
"""Dump json bytes with keys sorted."""
def json_dumps_sorted(data: Any) -> str:
"""Dump json string with keys sorted."""
return json_bytes_sorted(data).decode("utf-8")
JSON_DUMP: Final = json_dumps
def _orjson_default_encoder(data: Any) -> str:
"""JSON encoder that uses orjson with hass defaults and returns a str."""
return _orjson_bytes_default_encoder(data).decode("utf-8")
def _orjson_bytes_default_encoder(data: Any) -> bytes:
"""JSON encoder that uses orjson with hass defaults and returns bytes."""
return orjson.dumps(
data,
option=orjson.OPT_INDENT_2 | orjson.OPT_NON_STR_KEYS,
default=json_encoder_default,
)
def save_json(
filename: str,
data: list | dict,
private: bool = False,
*,
encoder: type[json.JSONEncoder] | None = None,
atomic_writes: bool = False,
) -> None:
"""Save JSON data to a file."""
dump: Callable[[Any], Any]
try:
# For backwards compatibility, if they pass in the
# default json encoder we use _orjson_default_encoder
# which is the orjson equivalent to the default encoder.
if encoder and encoder is not JSONEncoder:
# If they pass a custom encoder that is not the
# default JSONEncoder, we use the slow path of json.dumps
mode = "w"
dump = json.dumps
json_data: str | bytes = json.dumps(data, indent=2, cls=encoder)
else:
mode = "wb"
dump = _orjson_default_encoder
json_data = _orjson_bytes_default_encoder(data)
except TypeError as error:
formatted_data = format_unserializable_data(
find_paths_unserializable_data(data, dump=dump)
)
msg = f"Failed to serialize to JSON: {filename}. Bad data at {formatted_data}"
_LOGGER.error(msg)
raise SerializationError(msg) from error
method = write_utf8_file_atomic if atomic_writes else write_utf8_file
method(filename, json_data, private, mode=mode)
def find_paths_unserializable_data(
bad_data: Any, *, dump: Callable[[Any], str] = json.dumps
) -> dict[str, Any]:
"""Find the paths to unserializable data.
This method is slow! Only use for error handling.
"""
from homeassistant.core import ( # pylint: disable=import-outside-toplevel
Event,
State,
)
to_process = deque([(bad_data, "$")])
invalid = {}
while to_process:
obj, obj_path = to_process.popleft()
try:
dump(obj)
continue
except (ValueError, TypeError):
pass
# We convert objects with as_dict to their dict values
# so we can find bad data inside it
if hasattr(obj, "as_dict"):
desc = obj.__class__.__name__
if isinstance(obj, State):
desc += f": {obj.entity_id}"
elif isinstance(obj, Event):
desc += f": {obj.event_type}"
obj_path += f"({desc})"
obj = obj.as_dict()
if isinstance(obj, dict):
for key, value in obj.items():
try:
# Is key valid?
dump({key: None})
except TypeError:
invalid[f"{obj_path}<key: {key}>"] = key
else:
# Process value
to_process.append((value, f"{obj_path}.{key}"))
elif isinstance(obj, list):
for idx, value in enumerate(obj):
to_process.append((value, f"{obj_path}[{idx}]"))
else:
invalid[obj_path] = obj
return invalid