You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
311 lines
10 KiB
Python
311 lines
10 KiB
Python
from __future__ import annotations
|
|
|
|
import dataclasses
|
|
import decimal
|
|
import json
|
|
import typing as t
|
|
import uuid
|
|
import weakref
|
|
from datetime import date
|
|
|
|
from werkzeug.http import http_date
|
|
|
|
from ..globals import request
|
|
|
|
if t.TYPE_CHECKING: # pragma: no cover
|
|
from ..app import Flask
|
|
from ..wrappers import Response
|
|
|
|
|
|
class JSONProvider:
|
|
"""A standard set of JSON operations for an application. Subclasses
|
|
of this can be used to customize JSON behavior or use different
|
|
JSON libraries.
|
|
|
|
To implement a provider for a specific library, subclass this base
|
|
class and implement at least :meth:`dumps` and :meth:`loads`. All
|
|
other methods have default implementations.
|
|
|
|
To use a different provider, either subclass ``Flask`` and set
|
|
:attr:`~flask.Flask.json_provider_class` to a provider class, or set
|
|
:attr:`app.json <flask.Flask.json>` to an instance of the class.
|
|
|
|
:param app: An application instance. This will be stored as a
|
|
:class:`weakref.proxy` on the :attr:`_app` attribute.
|
|
|
|
.. versionadded:: 2.2
|
|
"""
|
|
|
|
def __init__(self, app: Flask) -> None:
|
|
self._app = weakref.proxy(app)
|
|
|
|
def dumps(self, obj: t.Any, **kwargs: t.Any) -> str:
|
|
"""Serialize data as JSON.
|
|
|
|
:param obj: The data to serialize.
|
|
:param kwargs: May be passed to the underlying JSON library.
|
|
"""
|
|
raise NotImplementedError
|
|
|
|
def dump(self, obj: t.Any, fp: t.IO[str], **kwargs: t.Any) -> None:
|
|
"""Serialize data as JSON and write to a file.
|
|
|
|
:param obj: The data to serialize.
|
|
:param fp: A file opened for writing text. Should use the UTF-8
|
|
encoding to be valid JSON.
|
|
:param kwargs: May be passed to the underlying JSON library.
|
|
"""
|
|
fp.write(self.dumps(obj, **kwargs))
|
|
|
|
def loads(self, s: str | bytes, **kwargs: t.Any) -> t.Any:
|
|
"""Deserialize data as JSON.
|
|
|
|
:param s: Text or UTF-8 bytes.
|
|
:param kwargs: May be passed to the underlying JSON library.
|
|
"""
|
|
raise NotImplementedError
|
|
|
|
def load(self, fp: t.IO[t.AnyStr], **kwargs: t.Any) -> t.Any:
|
|
"""Deserialize data as JSON read from a file.
|
|
|
|
:param fp: A file opened for reading text or UTF-8 bytes.
|
|
:param kwargs: May be passed to the underlying JSON library.
|
|
"""
|
|
return self.loads(fp.read(), **kwargs)
|
|
|
|
def _prepare_response_obj(
|
|
self, args: t.Tuple[t.Any, ...], kwargs: t.Dict[str, t.Any]
|
|
) -> t.Any:
|
|
if args and kwargs:
|
|
raise TypeError("app.json.response() takes either args or kwargs, not both")
|
|
|
|
if not args and not kwargs:
|
|
return None
|
|
|
|
if len(args) == 1:
|
|
return args[0]
|
|
|
|
return args or kwargs
|
|
|
|
def response(self, *args: t.Any, **kwargs: t.Any) -> Response:
|
|
"""Serialize the given arguments as JSON, and return a
|
|
:class:`~flask.Response` object with the ``application/json``
|
|
mimetype.
|
|
|
|
The :func:`~flask.json.jsonify` function calls this method for
|
|
the current application.
|
|
|
|
Either positional or keyword arguments can be given, not both.
|
|
If no arguments are given, ``None`` is serialized.
|
|
|
|
:param args: A single value to serialize, or multiple values to
|
|
treat as a list to serialize.
|
|
:param kwargs: Treat as a dict to serialize.
|
|
"""
|
|
obj = self._prepare_response_obj(args, kwargs)
|
|
return self._app.response_class(self.dumps(obj), mimetype="application/json")
|
|
|
|
|
|
def _default(o: t.Any) -> t.Any:
|
|
if isinstance(o, date):
|
|
return http_date(o)
|
|
|
|
if isinstance(o, (decimal.Decimal, uuid.UUID)):
|
|
return str(o)
|
|
|
|
if dataclasses and dataclasses.is_dataclass(o):
|
|
return dataclasses.asdict(o)
|
|
|
|
if hasattr(o, "__html__"):
|
|
return str(o.__html__())
|
|
|
|
raise TypeError(f"Object of type {type(o).__name__} is not JSON serializable")
|
|
|
|
|
|
class DefaultJSONProvider(JSONProvider):
|
|
"""Provide JSON operations using Python's built-in :mod:`json`
|
|
library. Serializes the following additional data types:
|
|
|
|
- :class:`datetime.datetime` and :class:`datetime.date` are
|
|
serialized to :rfc:`822` strings. This is the same as the HTTP
|
|
date format.
|
|
- :class:`uuid.UUID` is serialized to a string.
|
|
- :class:`dataclasses.dataclass` is passed to
|
|
:func:`dataclasses.asdict`.
|
|
- :class:`~markupsafe.Markup` (or any object with a ``__html__``
|
|
method) will call the ``__html__`` method to get a string.
|
|
"""
|
|
|
|
default: t.Callable[[t.Any], t.Any] = staticmethod(
|
|
_default
|
|
) # type: ignore[assignment]
|
|
"""Apply this function to any object that :meth:`json.dumps` does
|
|
not know how to serialize. It should return a valid JSON type or
|
|
raise a ``TypeError``.
|
|
"""
|
|
|
|
ensure_ascii = True
|
|
"""Replace non-ASCII characters with escape sequences. This may be
|
|
more compatible with some clients, but can be disabled for better
|
|
performance and size.
|
|
"""
|
|
|
|
sort_keys = True
|
|
"""Sort the keys in any serialized dicts. This may be useful for
|
|
some caching situations, but can be disabled for better performance.
|
|
When enabled, keys must all be strings, they are not converted
|
|
before sorting.
|
|
"""
|
|
|
|
compact: bool | None = None
|
|
"""If ``True``, or ``None`` out of debug mode, the :meth:`response`
|
|
output will not add indentation, newlines, or spaces. If ``False``,
|
|
or ``None`` in debug mode, it will use a non-compact representation.
|
|
"""
|
|
|
|
mimetype = "application/json"
|
|
"""The mimetype set in :meth:`response`."""
|
|
|
|
def dumps(self, obj: t.Any, **kwargs: t.Any) -> str:
|
|
"""Serialize data as JSON to a string.
|
|
|
|
Keyword arguments are passed to :func:`json.dumps`. Sets some
|
|
parameter defaults from the :attr:`default`,
|
|
:attr:`ensure_ascii`, and :attr:`sort_keys` attributes.
|
|
|
|
:param obj: The data to serialize.
|
|
:param kwargs: Passed to :func:`json.dumps`.
|
|
"""
|
|
cls = self._app._json_encoder
|
|
bp = self._app.blueprints.get(request.blueprint) if request else None
|
|
|
|
if bp is not None and bp._json_encoder is not None:
|
|
cls = bp._json_encoder
|
|
|
|
if cls is not None:
|
|
import warnings
|
|
|
|
warnings.warn(
|
|
"Setting 'json_encoder' on the app or a blueprint is"
|
|
" deprecated and will be removed in Flask 2.3."
|
|
" Customize 'app.json' instead.",
|
|
DeprecationWarning,
|
|
)
|
|
kwargs.setdefault("cls", cls)
|
|
|
|
if "default" not in cls.__dict__:
|
|
kwargs.setdefault("default", self.default)
|
|
else:
|
|
kwargs.setdefault("default", self.default)
|
|
|
|
ensure_ascii = self._app.config["JSON_AS_ASCII"]
|
|
sort_keys = self._app.config["JSON_SORT_KEYS"]
|
|
|
|
if ensure_ascii is not None:
|
|
import warnings
|
|
|
|
warnings.warn(
|
|
"The 'JSON_AS_ASCII' config key is deprecated and will"
|
|
" be removed in Flask 2.3. Set 'app.json.ensure_ascii'"
|
|
" instead.",
|
|
DeprecationWarning,
|
|
)
|
|
else:
|
|
ensure_ascii = self.ensure_ascii
|
|
|
|
if sort_keys is not None:
|
|
import warnings
|
|
|
|
warnings.warn(
|
|
"The 'JSON_SORT_KEYS' config key is deprecated and will"
|
|
" be removed in Flask 2.3. Set 'app.json.sort_keys'"
|
|
" instead.",
|
|
DeprecationWarning,
|
|
)
|
|
else:
|
|
sort_keys = self.sort_keys
|
|
|
|
kwargs.setdefault("ensure_ascii", ensure_ascii)
|
|
kwargs.setdefault("sort_keys", sort_keys)
|
|
return json.dumps(obj, **kwargs)
|
|
|
|
def loads(self, s: str | bytes, **kwargs: t.Any) -> t.Any:
|
|
"""Deserialize data as JSON from a string or bytes.
|
|
|
|
:param s: Text or UTF-8 bytes.
|
|
:param kwargs: Passed to :func:`json.loads`.
|
|
"""
|
|
cls = self._app._json_decoder
|
|
bp = self._app.blueprints.get(request.blueprint) if request else None
|
|
|
|
if bp is not None and bp._json_decoder is not None:
|
|
cls = bp._json_decoder
|
|
|
|
if cls is not None:
|
|
import warnings
|
|
|
|
warnings.warn(
|
|
"Setting 'json_decoder' on the app or a blueprint is"
|
|
" deprecated and will be removed in Flask 2.3."
|
|
" Customize 'app.json' instead.",
|
|
DeprecationWarning,
|
|
)
|
|
kwargs.setdefault("cls", cls)
|
|
|
|
return json.loads(s, **kwargs)
|
|
|
|
def response(self, *args: t.Any, **kwargs: t.Any) -> Response:
|
|
"""Serialize the given arguments as JSON, and return a
|
|
:class:`~flask.Response` object with it. The response mimetype
|
|
will be "application/json" and can be changed with
|
|
:attr:`mimetype`.
|
|
|
|
If :attr:`compact` is ``False`` or debug mode is enabled, the
|
|
output will be formatted to be easier to read.
|
|
|
|
Either positional or keyword arguments can be given, not both.
|
|
If no arguments are given, ``None`` is serialized.
|
|
|
|
:param args: A single value to serialize, or multiple values to
|
|
treat as a list to serialize.
|
|
:param kwargs: Treat as a dict to serialize.
|
|
"""
|
|
obj = self._prepare_response_obj(args, kwargs)
|
|
dump_args: t.Dict[str, t.Any] = {}
|
|
pretty = self._app.config["JSONIFY_PRETTYPRINT_REGULAR"]
|
|
mimetype = self._app.config["JSONIFY_MIMETYPE"]
|
|
|
|
if pretty is not None:
|
|
import warnings
|
|
|
|
warnings.warn(
|
|
"The 'JSONIFY_PRETTYPRINT_REGULAR' config key is"
|
|
" deprecated and will be removed in Flask 2.3. Set"
|
|
" 'app.json.compact' instead.",
|
|
DeprecationWarning,
|
|
)
|
|
compact: bool | None = not pretty
|
|
else:
|
|
compact = self.compact
|
|
|
|
if (compact is None and self._app.debug) or compact is False:
|
|
dump_args.setdefault("indent", 2)
|
|
else:
|
|
dump_args.setdefault("separators", (",", ":"))
|
|
|
|
if mimetype is not None:
|
|
import warnings
|
|
|
|
warnings.warn(
|
|
"The 'JSONIFY_MIMETYPE' config key is deprecated and"
|
|
" will be removed in Flask 2.3. Set 'app.json.mimetype'"
|
|
" instead.",
|
|
DeprecationWarning,
|
|
)
|
|
else:
|
|
mimetype = self.mimetype
|
|
|
|
return self._app.response_class(
|
|
f"{self.dumps(obj, **dump_args)}\n", mimetype=mimetype
|
|
)
|