zulip/zerver/lib/response.py

140 lines
5.2 KiB
Python

from collections.abc import Iterator, Mapping
from typing import Any
import orjson
from django.http import HttpRequest, HttpResponse, HttpResponseNotAllowed
from typing_extensions import override
from zerver.lib.exceptions import JsonableError, UnauthorizedError
class MutableJsonResponse(HttpResponse):
def __init__(
self,
data: dict[str, Any],
*,
content_type: str,
status: int,
) -> None:
# Mirror the behavior of Django's TemplateResponse and pass an
# empty string for the initial content value. Because that will
# set _needs_serialization to False, we initialize it to True
# after the call to super __init__.
super().__init__("", content_type=content_type, status=status)
self._data = data
self._needs_serialization = True
def get_data(self) -> dict[str, Any]:
"""Get data for this MutableJsonResponse. Calling this method
after the response's content has already been serialized
will mean the next time the response's content is accessed
it will be reserialized because the caller may have mutated
the data."""
self._needs_serialization = True
return self._data
# This always returns bytes, but in Django's HttpResponse the return
# value can be bytes, an iterable of bytes or some other object. Any
# is used here to encompass all of those return values.
# See https://github.com/typeddjango/django-stubs/commit/799b41fe47cfe2e56be33eee8cfbaf89a9853a8e
# and https://github.com/python/mypy/issues/3004.
@override # type: ignore[explicit-override] # https://github.com/python/mypy/issues/15900
@property
def content(self) -> Any:
"""Get content for the response. If the content hasn't been
overridden by the property setter, it will be the response data
serialized lazily to JSON."""
if self._needs_serialization:
# Because we don't pass a default handler, OPT_PASSTHROUGH_DATETIME
# actually causes orjson to raise a TypeError on datetime objects. This
# helps us avoid relying on the particular serialization used by orjson.
self.content = orjson.dumps(
self._data,
option=orjson.OPT_APPEND_NEWLINE | orjson.OPT_PASSTHROUGH_DATETIME,
)
return super().content
# There are two ways this might be called. The first is in the getter when
# the response data is being serialized into JSON. The second is when it
# is called from some other part of the code. This happens for instance in
# the parent class constructor. In this case, the new content overrides the
# serialized JSON.
@content.setter
def content(self, value: Any) -> None:
"""Set the content for the response."""
assert isinstance(HttpResponse.content, property)
assert HttpResponse.content.fset is not None
HttpResponse.content.fset(self, value)
self._needs_serialization = False
# The superclass HttpResponse defines an iterator that doesn't access the content
# property, so in order to not break the implementation of the superclass with
# our lazy content generation, we override the iterator to access `self.content`
# through our getter.
@override
def __iter__(self) -> Iterator[bytes]:
return iter([self.content])
def json_unauthorized(
message: str | None = None, www_authenticate: str | None = None
) -> HttpResponse:
return json_response_from_error(
UnauthorizedError(msg=message, www_authenticate=www_authenticate)
)
def json_method_not_allowed(methods: list[str]) -> HttpResponseNotAllowed:
resp = HttpResponseNotAllowed(methods)
resp.content = orjson.dumps(
{"result": "error", "msg": "Method Not Allowed", "allowed_methods": methods}
)
return resp
def json_response(
res_type: str = "success", msg: str = "", data: Mapping[str, Any] = {}, status: int = 200
) -> MutableJsonResponse:
content = {"result": res_type, "msg": msg}
content.update(data)
return MutableJsonResponse(
data=content,
content_type="application/json",
status=status,
)
def json_success(request: HttpRequest, data: Mapping[str, Any] = {}) -> MutableJsonResponse:
return json_response(data=data)
def json_response_from_error(exception: JsonableError) -> MutableJsonResponse:
"""
This should only be needed in middleware; in app code, just raise.
When app code raises a JsonableError, the JsonErrorHandler
middleware takes care of transforming it into a response by
calling this function.
"""
response_type = "error"
if 200 <= exception.http_status_code < 300:
response_type = "success"
response = json_response(
response_type, msg=exception.msg, data=exception.data, status=exception.http_status_code
)
for header, value in exception.extra_headers.items():
response[header] = value
return response
class AsynchronousResponse(HttpResponse):
"""
This response is just a sentinel to be discarded by Tornado and replaced
with a real response later; see zulip_finish.
"""
status_code = 399