Coverage for /pythoncovmergedfiles/medio/medio/usr/local/lib/python3.8/site-packages/werkzeug/formparser.py: 26%
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1from __future__ import annotations
3import typing as t
4from io import BytesIO
5from urllib.parse import parse_qsl
7from ._internal import _plain_int
8from .datastructures import FileStorage
9from .datastructures import Headers
10from .datastructures import MultiDict
11from .exceptions import RequestEntityTooLarge
12from .http import parse_options_header
13from .sansio.multipart import Data
14from .sansio.multipart import Epilogue
15from .sansio.multipart import Field
16from .sansio.multipart import File
17from .sansio.multipart import MultipartDecoder
18from .sansio.multipart import NeedData
19from .wsgi import get_content_length
20from .wsgi import get_input_stream
22# there are some platforms where SpooledTemporaryFile is not available.
23# In that case we need to provide a fallback.
24try:
25 from tempfile import SpooledTemporaryFile
26except ImportError:
27 from tempfile import TemporaryFile
29 SpooledTemporaryFile = None # type: ignore
31if t.TYPE_CHECKING:
32 import typing as te
34 from _typeshed.wsgi import WSGIEnvironment
36 t_parse_result = t.Tuple[
37 t.IO[bytes], MultiDict[str, str], MultiDict[str, FileStorage]
38 ]
40 class TStreamFactory(te.Protocol):
41 def __call__(
42 self,
43 total_content_length: int | None,
44 content_type: str | None,
45 filename: str | None,
46 content_length: int | None = None,
47 ) -> t.IO[bytes]: ...
50F = t.TypeVar("F", bound=t.Callable[..., t.Any])
53def default_stream_factory(
54 total_content_length: int | None,
55 content_type: str | None,
56 filename: str | None,
57 content_length: int | None = None,
58) -> t.IO[bytes]:
59 max_size = 1024 * 500
61 if SpooledTemporaryFile is not None:
62 return t.cast(t.IO[bytes], SpooledTemporaryFile(max_size=max_size, mode="rb+"))
63 elif total_content_length is None or total_content_length > max_size:
64 return t.cast(t.IO[bytes], TemporaryFile("rb+"))
66 return BytesIO()
69def parse_form_data(
70 environ: WSGIEnvironment,
71 stream_factory: TStreamFactory | None = None,
72 max_form_memory_size: int | None = None,
73 max_content_length: int | None = None,
74 cls: type[MultiDict[str, t.Any]] | None = None,
75 silent: bool = True,
76 *,
77 max_form_parts: int | None = None,
78) -> t_parse_result:
79 """Parse the form data in the environ and return it as tuple in the form
80 ``(stream, form, files)``. You should only call this method if the
81 transport method is `POST`, `PUT`, or `PATCH`.
83 If the mimetype of the data transmitted is `multipart/form-data` the
84 files multidict will be filled with `FileStorage` objects. If the
85 mimetype is unknown the input stream is wrapped and returned as first
86 argument, else the stream is empty.
88 This is a shortcut for the common usage of :class:`FormDataParser`.
90 :param environ: the WSGI environment to be used for parsing.
91 :param stream_factory: An optional callable that returns a new read and
92 writeable file descriptor. This callable works
93 the same as :meth:`Response._get_file_stream`.
94 :param max_form_memory_size: the maximum number of bytes to be accepted for
95 in-memory stored form data. If the data
96 exceeds the value specified an
97 :exc:`~exceptions.RequestEntityTooLarge`
98 exception is raised.
99 :param max_content_length: If this is provided and the transmitted data
100 is longer than this value an
101 :exc:`~exceptions.RequestEntityTooLarge`
102 exception is raised.
103 :param cls: an optional dict class to use. If this is not specified
104 or `None` the default :class:`MultiDict` is used.
105 :param silent: If set to False parsing errors will not be caught.
106 :param max_form_parts: The maximum number of multipart parts to be parsed. If this
107 is exceeded, a :exc:`~exceptions.RequestEntityTooLarge` exception is raised.
108 :return: A tuple in the form ``(stream, form, files)``.
110 .. versionchanged:: 3.0
111 The ``charset`` and ``errors`` parameters were removed.
113 .. versionchanged:: 2.3
114 Added the ``max_form_parts`` parameter.
116 .. versionadded:: 0.5.1
117 Added the ``silent`` parameter.
119 .. versionadded:: 0.5
120 Added the ``max_form_memory_size``, ``max_content_length``, and ``cls``
121 parameters.
122 """
123 return FormDataParser(
124 stream_factory=stream_factory,
125 max_form_memory_size=max_form_memory_size,
126 max_content_length=max_content_length,
127 max_form_parts=max_form_parts,
128 silent=silent,
129 cls=cls,
130 ).parse_from_environ(environ)
133class FormDataParser:
134 """This class implements parsing of form data for Werkzeug. By itself
135 it can parse multipart and url encoded form data. It can be subclassed
136 and extended but for most mimetypes it is a better idea to use the
137 untouched stream and expose it as separate attributes on a request
138 object.
140 :param stream_factory: An optional callable that returns a new read and
141 writeable file descriptor. This callable works
142 the same as :meth:`Response._get_file_stream`.
143 :param max_form_memory_size: the maximum number of bytes to be accepted for
144 in-memory stored form data. If the data
145 exceeds the value specified an
146 :exc:`~exceptions.RequestEntityTooLarge`
147 exception is raised.
148 :param max_content_length: If this is provided and the transmitted data
149 is longer than this value an
150 :exc:`~exceptions.RequestEntityTooLarge`
151 exception is raised.
152 :param cls: an optional dict class to use. If this is not specified
153 or `None` the default :class:`MultiDict` is used.
154 :param silent: If set to False parsing errors will not be caught.
155 :param max_form_parts: The maximum number of multipart parts to be parsed. If this
156 is exceeded, a :exc:`~exceptions.RequestEntityTooLarge` exception is raised.
158 .. versionchanged:: 3.0
159 The ``charset`` and ``errors`` parameters were removed.
161 .. versionchanged:: 3.0
162 The ``parse_functions`` attribute and ``get_parse_func`` methods were removed.
164 .. versionchanged:: 2.2.3
165 Added the ``max_form_parts`` parameter.
167 .. versionadded:: 0.8
168 """
170 def __init__(
171 self,
172 stream_factory: TStreamFactory | None = None,
173 max_form_memory_size: int | None = None,
174 max_content_length: int | None = None,
175 cls: type[MultiDict[str, t.Any]] | None = None,
176 silent: bool = True,
177 *,
178 max_form_parts: int | None = None,
179 ) -> None:
180 if stream_factory is None:
181 stream_factory = default_stream_factory
183 self.stream_factory = stream_factory
184 self.max_form_memory_size = max_form_memory_size
185 self.max_content_length = max_content_length
186 self.max_form_parts = max_form_parts
188 if cls is None:
189 cls = t.cast("type[MultiDict[str, t.Any]]", MultiDict)
191 self.cls = cls
192 self.silent = silent
194 def parse_from_environ(self, environ: WSGIEnvironment) -> t_parse_result:
195 """Parses the information from the environment as form data.
197 :param environ: the WSGI environment to be used for parsing.
198 :return: A tuple in the form ``(stream, form, files)``.
199 """
200 stream = get_input_stream(environ, max_content_length=self.max_content_length)
201 content_length = get_content_length(environ)
202 mimetype, options = parse_options_header(environ.get("CONTENT_TYPE"))
203 return self.parse(
204 stream,
205 content_length=content_length,
206 mimetype=mimetype,
207 options=options,
208 )
210 def parse(
211 self,
212 stream: t.IO[bytes],
213 mimetype: str,
214 content_length: int | None,
215 options: dict[str, str] | None = None,
216 ) -> t_parse_result:
217 """Parses the information from the given stream, mimetype,
218 content length and mimetype parameters.
220 :param stream: an input stream
221 :param mimetype: the mimetype of the data
222 :param content_length: the content length of the incoming data
223 :param options: optional mimetype parameters (used for
224 the multipart boundary for instance)
225 :return: A tuple in the form ``(stream, form, files)``.
227 .. versionchanged:: 3.0
228 The invalid ``application/x-url-encoded`` content type is not
229 treated as ``application/x-www-form-urlencoded``.
230 """
231 if mimetype == "multipart/form-data":
232 parse_func = self._parse_multipart
233 elif mimetype == "application/x-www-form-urlencoded":
234 parse_func = self._parse_urlencoded
235 else:
236 return stream, self.cls(), self.cls()
238 if options is None:
239 options = {}
241 try:
242 return parse_func(stream, mimetype, content_length, options)
243 except ValueError:
244 if not self.silent:
245 raise
247 return stream, self.cls(), self.cls()
249 def _parse_multipart(
250 self,
251 stream: t.IO[bytes],
252 mimetype: str,
253 content_length: int | None,
254 options: dict[str, str],
255 ) -> t_parse_result:
256 parser = MultiPartParser(
257 stream_factory=self.stream_factory,
258 max_form_memory_size=self.max_form_memory_size,
259 max_form_parts=self.max_form_parts,
260 cls=self.cls,
261 )
262 boundary = options.get("boundary", "").encode("ascii")
264 if not boundary:
265 raise ValueError("Missing boundary")
267 form, files = parser.parse(stream, boundary, content_length)
268 return stream, form, files
270 def _parse_urlencoded(
271 self,
272 stream: t.IO[bytes],
273 mimetype: str,
274 content_length: int | None,
275 options: dict[str, str],
276 ) -> t_parse_result:
277 if (
278 self.max_form_memory_size is not None
279 and content_length is not None
280 and content_length > self.max_form_memory_size
281 ):
282 raise RequestEntityTooLarge()
284 items = parse_qsl(
285 stream.read().decode(),
286 keep_blank_values=True,
287 errors="werkzeug.url_quote",
288 )
289 return stream, self.cls(items), self.cls()
292class MultiPartParser:
293 def __init__(
294 self,
295 stream_factory: TStreamFactory | None = None,
296 max_form_memory_size: int | None = None,
297 cls: type[MultiDict[str, t.Any]] | None = None,
298 buffer_size: int = 64 * 1024,
299 max_form_parts: int | None = None,
300 ) -> None:
301 self.max_form_memory_size = max_form_memory_size
302 self.max_form_parts = max_form_parts
304 if stream_factory is None:
305 stream_factory = default_stream_factory
307 self.stream_factory = stream_factory
309 if cls is None:
310 cls = t.cast("type[MultiDict[str, t.Any]]", MultiDict)
312 self.cls = cls
313 self.buffer_size = buffer_size
315 def fail(self, message: str) -> te.NoReturn:
316 raise ValueError(message)
318 def get_part_charset(self, headers: Headers) -> str:
319 # Figure out input charset for current part
320 content_type = headers.get("content-type")
322 if content_type:
323 parameters = parse_options_header(content_type)[1]
324 ct_charset = parameters.get("charset", "").lower()
326 # A safe list of encodings. Modern clients should only send ASCII or UTF-8.
327 # This list will not be extended further.
328 if ct_charset in {"ascii", "us-ascii", "utf-8", "iso-8859-1"}:
329 return ct_charset
331 return "utf-8"
333 def start_file_streaming(
334 self, event: File, total_content_length: int | None
335 ) -> t.IO[bytes]:
336 content_type = event.headers.get("content-type")
338 try:
339 content_length = _plain_int(event.headers["content-length"])
340 except (KeyError, ValueError):
341 content_length = 0
343 container = self.stream_factory(
344 total_content_length=total_content_length,
345 filename=event.filename,
346 content_type=content_type,
347 content_length=content_length,
348 )
349 return container
351 def parse(
352 self, stream: t.IO[bytes], boundary: bytes, content_length: int | None
353 ) -> tuple[MultiDict[str, str], MultiDict[str, FileStorage]]:
354 current_part: Field | File
355 container: t.IO[bytes] | list[bytes]
356 _write: t.Callable[[bytes], t.Any]
358 parser = MultipartDecoder(
359 boundary,
360 max_form_memory_size=self.max_form_memory_size,
361 max_parts=self.max_form_parts,
362 )
364 fields = []
365 files = []
367 for data in _chunk_iter(stream.read, self.buffer_size):
368 parser.receive_data(data)
369 event = parser.next_event()
370 while not isinstance(event, (Epilogue, NeedData)):
371 if isinstance(event, Field):
372 current_part = event
373 container = []
374 _write = container.append
375 elif isinstance(event, File):
376 current_part = event
377 container = self.start_file_streaming(event, content_length)
378 _write = container.write
379 elif isinstance(event, Data):
380 _write(event.data)
381 if not event.more_data:
382 if isinstance(current_part, Field):
383 value = b"".join(container).decode(
384 self.get_part_charset(current_part.headers), "replace"
385 )
386 fields.append((current_part.name, value))
387 else:
388 container = t.cast(t.IO[bytes], container)
389 container.seek(0)
390 files.append(
391 (
392 current_part.name,
393 FileStorage(
394 container,
395 current_part.filename,
396 current_part.name,
397 headers=current_part.headers,
398 ),
399 )
400 )
402 event = parser.next_event()
404 return self.cls(fields), self.cls(files)
407def _chunk_iter(read: t.Callable[[int], bytes], size: int) -> t.Iterator[bytes | None]:
408 """Read data in chunks for multipart/form-data parsing. Stop if no data is read.
409 Yield ``None`` at the end to signal end of parsing.
410 """
411 while True:
412 data = read(size)
414 if not data:
415 break
417 yield data
419 yield None