File size: 16,474 Bytes
9c6594c |
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 |
import asyncio
import io
import os
import pathlib
import sys
from contextlib import suppress
from enum import Enum, auto
from mimetypes import MimeTypes
from stat import S_ISREG
from types import MappingProxyType
from typing import ( # noqa
IO,
TYPE_CHECKING,
Any,
Awaitable,
Callable,
Final,
Iterator,
List,
Optional,
Set,
Tuple,
Union,
cast,
)
from . import hdrs
from .abc import AbstractStreamWriter
from .helpers import ETAG_ANY, ETag, must_be_empty_body
from .typedefs import LooseHeaders, PathLike
from .web_exceptions import (
HTTPForbidden,
HTTPNotFound,
HTTPNotModified,
HTTPPartialContent,
HTTPPreconditionFailed,
HTTPRequestRangeNotSatisfiable,
)
from .web_response import StreamResponse
__all__ = ("FileResponse",)
if TYPE_CHECKING:
from .web_request import BaseRequest
_T_OnChunkSent = Optional[Callable[[bytes], Awaitable[None]]]
NOSENDFILE: Final[bool] = bool(os.environ.get("AIOHTTP_NOSENDFILE"))
CONTENT_TYPES: Final[MimeTypes] = MimeTypes()
# File extension to IANA encodings map that will be checked in the order defined.
ENCODING_EXTENSIONS = MappingProxyType(
{ext: CONTENT_TYPES.encodings_map[ext] for ext in (".br", ".gz")}
)
FALLBACK_CONTENT_TYPE = "application/octet-stream"
# Provide additional MIME type/extension pairs to be recognized.
# https://en.wikipedia.org/wiki/List_of_archive_formats#Compression_only
ADDITIONAL_CONTENT_TYPES = MappingProxyType(
{
"application/gzip": ".gz",
"application/x-brotli": ".br",
"application/x-bzip2": ".bz2",
"application/x-compress": ".Z",
"application/x-xz": ".xz",
}
)
class _FileResponseResult(Enum):
"""The result of the file response."""
SEND_FILE = auto() # Ie a regular file to send
NOT_ACCEPTABLE = auto() # Ie a socket, or non-regular file
PRE_CONDITION_FAILED = auto() # Ie If-Match or If-None-Match failed
NOT_MODIFIED = auto() # 304 Not Modified
# Add custom pairs and clear the encodings map so guess_type ignores them.
CONTENT_TYPES.encodings_map.clear()
for content_type, extension in ADDITIONAL_CONTENT_TYPES.items():
CONTENT_TYPES.add_type(content_type, extension)
_CLOSE_FUTURES: Set[asyncio.Future[None]] = set()
class FileResponse(StreamResponse):
"""A response object can be used to send files."""
def __init__(
self,
path: PathLike,
chunk_size: int = 256 * 1024,
status: int = 200,
reason: Optional[str] = None,
headers: Optional[LooseHeaders] = None,
) -> None:
super().__init__(status=status, reason=reason, headers=headers)
self._path = pathlib.Path(path)
self._chunk_size = chunk_size
def _seek_and_read(self, fobj: IO[Any], offset: int, chunk_size: int) -> bytes:
fobj.seek(offset)
return fobj.read(chunk_size) # type: ignore[no-any-return]
async def _sendfile_fallback(
self, writer: AbstractStreamWriter, fobj: IO[Any], offset: int, count: int
) -> AbstractStreamWriter:
# To keep memory usage low,fobj is transferred in chunks
# controlled by the constructor's chunk_size argument.
chunk_size = self._chunk_size
loop = asyncio.get_event_loop()
chunk = await loop.run_in_executor(
None, self._seek_and_read, fobj, offset, chunk_size
)
while chunk:
await writer.write(chunk)
count = count - chunk_size
if count <= 0:
break
chunk = await loop.run_in_executor(None, fobj.read, min(chunk_size, count))
await writer.drain()
return writer
async def _sendfile(
self, request: "BaseRequest", fobj: IO[Any], offset: int, count: int
) -> AbstractStreamWriter:
writer = await super().prepare(request)
assert writer is not None
if NOSENDFILE or self.compression:
return await self._sendfile_fallback(writer, fobj, offset, count)
loop = request._loop
transport = request.transport
assert transport is not None
try:
await loop.sendfile(transport, fobj, offset, count)
except NotImplementedError:
return await self._sendfile_fallback(writer, fobj, offset, count)
await super().write_eof()
return writer
@staticmethod
def _etag_match(etag_value: str, etags: Tuple[ETag, ...], *, weak: bool) -> bool:
if len(etags) == 1 and etags[0].value == ETAG_ANY:
return True
return any(
etag.value == etag_value for etag in etags if weak or not etag.is_weak
)
async def _not_modified(
self, request: "BaseRequest", etag_value: str, last_modified: float
) -> Optional[AbstractStreamWriter]:
self.set_status(HTTPNotModified.status_code)
self._length_check = False
self.etag = etag_value # type: ignore[assignment]
self.last_modified = last_modified # type: ignore[assignment]
# Delete any Content-Length headers provided by user. HTTP 304
# should always have empty response body
return await super().prepare(request)
async def _precondition_failed(
self, request: "BaseRequest"
) -> Optional[AbstractStreamWriter]:
self.set_status(HTTPPreconditionFailed.status_code)
self.content_length = 0
return await super().prepare(request)
def _make_response(
self, request: "BaseRequest", accept_encoding: str
) -> Tuple[
_FileResponseResult, Optional[io.BufferedReader], os.stat_result, Optional[str]
]:
"""Return the response result, io object, stat result, and encoding.
If an uncompressed file is returned, the encoding is set to
:py:data:`None`.
This method should be called from a thread executor
since it calls os.stat which may block.
"""
file_path, st, file_encoding = self._get_file_path_stat_encoding(
accept_encoding
)
if not file_path:
return _FileResponseResult.NOT_ACCEPTABLE, None, st, None
etag_value = f"{st.st_mtime_ns:x}-{st.st_size:x}"
# https://www.rfc-editor.org/rfc/rfc9110#section-13.1.1-2
if (ifmatch := request.if_match) is not None and not self._etag_match(
etag_value, ifmatch, weak=False
):
return _FileResponseResult.PRE_CONDITION_FAILED, None, st, file_encoding
if (
(unmodsince := request.if_unmodified_since) is not None
and ifmatch is None
and st.st_mtime > unmodsince.timestamp()
):
return _FileResponseResult.PRE_CONDITION_FAILED, None, st, file_encoding
# https://www.rfc-editor.org/rfc/rfc9110#section-13.1.2-2
if (ifnonematch := request.if_none_match) is not None and self._etag_match(
etag_value, ifnonematch, weak=True
):
return _FileResponseResult.NOT_MODIFIED, None, st, file_encoding
if (
(modsince := request.if_modified_since) is not None
and ifnonematch is None
and st.st_mtime <= modsince.timestamp()
):
return _FileResponseResult.NOT_MODIFIED, None, st, file_encoding
fobj = file_path.open("rb")
with suppress(OSError):
# fstat() may not be available on all platforms
# Once we open the file, we want the fstat() to ensure
# the file has not changed between the first stat()
# and the open().
st = os.stat(fobj.fileno())
return _FileResponseResult.SEND_FILE, fobj, st, file_encoding
def _get_file_path_stat_encoding(
self, accept_encoding: str
) -> Tuple[Optional[pathlib.Path], os.stat_result, Optional[str]]:
file_path = self._path
for file_extension, file_encoding in ENCODING_EXTENSIONS.items():
if file_encoding not in accept_encoding:
continue
compressed_path = file_path.with_suffix(file_path.suffix + file_extension)
with suppress(OSError):
# Do not follow symlinks and ignore any non-regular files.
st = compressed_path.lstat()
if S_ISREG(st.st_mode):
return compressed_path, st, file_encoding
# Fallback to the uncompressed file
st = file_path.stat()
return file_path if S_ISREG(st.st_mode) else None, st, None
async def prepare(self, request: "BaseRequest") -> Optional[AbstractStreamWriter]:
loop = asyncio.get_running_loop()
# Encoding comparisons should be case-insensitive
# https://www.rfc-editor.org/rfc/rfc9110#section-8.4.1
accept_encoding = request.headers.get(hdrs.ACCEPT_ENCODING, "").lower()
try:
response_result, fobj, st, file_encoding = await loop.run_in_executor(
None, self._make_response, request, accept_encoding
)
except PermissionError:
self.set_status(HTTPForbidden.status_code)
return await super().prepare(request)
except OSError:
# Most likely to be FileNotFoundError or OSError for circular
# symlinks in python >= 3.13, so respond with 404.
self.set_status(HTTPNotFound.status_code)
return await super().prepare(request)
# Forbid special files like sockets, pipes, devices, etc.
if response_result is _FileResponseResult.NOT_ACCEPTABLE:
self.set_status(HTTPForbidden.status_code)
return await super().prepare(request)
if response_result is _FileResponseResult.PRE_CONDITION_FAILED:
return await self._precondition_failed(request)
if response_result is _FileResponseResult.NOT_MODIFIED:
etag_value = f"{st.st_mtime_ns:x}-{st.st_size:x}"
last_modified = st.st_mtime
return await self._not_modified(request, etag_value, last_modified)
assert fobj is not None
try:
return await self._prepare_open_file(request, fobj, st, file_encoding)
finally:
# We do not await here because we do not want to wait
# for the executor to finish before returning the response
# so the connection can begin servicing another request
# as soon as possible.
close_future = loop.run_in_executor(None, fobj.close)
# Hold a strong reference to the future to prevent it from being
# garbage collected before it completes.
_CLOSE_FUTURES.add(close_future)
close_future.add_done_callback(_CLOSE_FUTURES.remove)
async def _prepare_open_file(
self,
request: "BaseRequest",
fobj: io.BufferedReader,
st: os.stat_result,
file_encoding: Optional[str],
) -> Optional[AbstractStreamWriter]:
status = self._status
file_size: int = st.st_size
file_mtime: float = st.st_mtime
count: int = file_size
start: Optional[int] = None
if (ifrange := request.if_range) is None or file_mtime <= ifrange.timestamp():
# If-Range header check:
# condition = cached date >= last modification date
# return 206 if True else 200.
# if False:
# Range header would not be processed, return 200
# if True but Range header missing
# return 200
try:
rng = request.http_range
start = rng.start
end: Optional[int] = rng.stop
except ValueError:
# https://tools.ietf.org/html/rfc7233:
# A server generating a 416 (Range Not Satisfiable) response to
# a byte-range request SHOULD send a Content-Range header field
# with an unsatisfied-range value.
# The complete-length in a 416 response indicates the current
# length of the selected representation.
#
# Will do the same below. Many servers ignore this and do not
# send a Content-Range header with HTTP 416
self._headers[hdrs.CONTENT_RANGE] = f"bytes */{file_size}"
self.set_status(HTTPRequestRangeNotSatisfiable.status_code)
return await super().prepare(request)
# If a range request has been made, convert start, end slice
# notation into file pointer offset and count
if start is not None:
if start < 0 and end is None: # return tail of file
start += file_size
if start < 0:
# if Range:bytes=-1000 in request header but file size
# is only 200, there would be trouble without this
start = 0
count = file_size - start
else:
# rfc7233:If the last-byte-pos value is
# absent, or if the value is greater than or equal to
# the current length of the representation data,
# the byte range is interpreted as the remainder
# of the representation (i.e., the server replaces the
# value of last-byte-pos with a value that is one less than
# the current length of the selected representation).
count = (
min(end if end is not None else file_size, file_size) - start
)
if start >= file_size:
# HTTP 416 should be returned in this case.
#
# According to https://tools.ietf.org/html/rfc7233:
# If a valid byte-range-set includes at least one
# byte-range-spec with a first-byte-pos that is less than
# the current length of the representation, or at least one
# suffix-byte-range-spec with a non-zero suffix-length,
# then the byte-range-set is satisfiable. Otherwise, the
# byte-range-set is unsatisfiable.
self._headers[hdrs.CONTENT_RANGE] = f"bytes */{file_size}"
self.set_status(HTTPRequestRangeNotSatisfiable.status_code)
return await super().prepare(request)
status = HTTPPartialContent.status_code
# Even though you are sending the whole file, you should still
# return a HTTP 206 for a Range request.
self.set_status(status)
# If the Content-Type header is not already set, guess it based on the
# extension of the request path. The encoding returned by guess_type
# can be ignored since the map was cleared above.
if hdrs.CONTENT_TYPE not in self._headers:
if sys.version_info >= (3, 13):
guesser = CONTENT_TYPES.guess_file_type
else:
guesser = CONTENT_TYPES.guess_type
self.content_type = guesser(self._path)[0] or FALLBACK_CONTENT_TYPE
if file_encoding:
self._headers[hdrs.CONTENT_ENCODING] = file_encoding
self._headers[hdrs.VARY] = hdrs.ACCEPT_ENCODING
# Disable compression if we are already sending
# a compressed file since we don't want to double
# compress.
self._compression = False
self.etag = f"{st.st_mtime_ns:x}-{st.st_size:x}" # type: ignore[assignment]
self.last_modified = file_mtime # type: ignore[assignment]
self.content_length = count
self._headers[hdrs.ACCEPT_RANGES] = "bytes"
if status == HTTPPartialContent.status_code:
real_start = start
assert real_start is not None
self._headers[hdrs.CONTENT_RANGE] = "bytes {}-{}/{}".format(
real_start, real_start + count - 1, file_size
)
# If we are sending 0 bytes calling sendfile() will throw a ValueError
if count == 0 or must_be_empty_body(request.method, status):
return await super().prepare(request)
# be aware that start could be None or int=0 here.
offset = start or 0
return await self._sendfile(request, fobj, offset, count)
|