import asyncio import mimetypes import os import pathlib from functools import partial from typing import ( # noqa IO, TYPE_CHECKING, Any, Awaitable, Callable, List, Optional, Union, cast, ) from . import hdrs from .abc import AbstractStreamWriter from .base_protocol import BaseProtocol from .helpers import set_exception, set_result from .http_writer import StreamWriter from .log import server_logger from .typedefs import LooseHeaders from .web_exceptions import ( HTTPNotModified, HTTPPartialContent, HTTPPreconditionFailed, HTTPRequestRangeNotSatisfiable, ) from .web_response import StreamResponse __all__ = ('FileResponse',) if TYPE_CHECKING: # pragma: no cover from .web_request import BaseRequest # noqa _T_OnChunkSent = Optional[Callable[[bytes], Awaitable[None]]] NOSENDFILE = bool(os.environ.get("AIOHTTP_NOSENDFILE")) class SendfileStreamWriter(StreamWriter): def __init__(self, protocol: BaseProtocol, loop: asyncio.AbstractEventLoop, fobj: IO[Any], count: int, on_chunk_sent: _T_OnChunkSent=None) -> None: super().__init__(protocol, loop, on_chunk_sent) self._sendfile_buffer = [] # type: List[bytes] self._fobj = fobj self._count = count self._offset = fobj.tell() self._in_fd = fobj.fileno() def _write(self, chunk: bytes) -> None: # we overwrite StreamWriter._write, so nothing can be appended to # _buffer, and nothing is written to the transport directly by the # parent class self.output_size += len(chunk) self._sendfile_buffer.append(chunk) def _sendfile_cb(self, fut: 'asyncio.Future[None]', out_fd: int) -> None: if fut.cancelled(): return try: if self._do_sendfile(out_fd): set_result(fut, None) except Exception as exc: set_exception(fut, exc) def _do_sendfile(self, out_fd: int) -> bool: try: n = os.sendfile(out_fd, self._in_fd, self._offset, self._count) if n == 0: # in_fd EOF reached n = self._count except (BlockingIOError, InterruptedError): n = 0 self.output_size += n self._offset += n self._count -= n assert self._count >= 0 return self._count == 0 def _done_fut(self, out_fd: int, fut: 'asyncio.Future[None]') -> None: self.loop.remove_writer(out_fd) async def sendfile(self) -> None: assert self.transport is not None out_socket = self.transport.get_extra_info('socket').dup() out_socket.setblocking(False) out_fd = out_socket.fileno() loop = self.loop data = b''.join(self._sendfile_buffer) try: await loop.sock_sendall(out_socket, data) if not self._do_sendfile(out_fd): fut = loop.create_future() fut.add_done_callback(partial(self._done_fut, out_fd)) loop.add_writer(out_fd, self._sendfile_cb, fut, out_fd) await fut except asyncio.CancelledError: raise except Exception: server_logger.debug('Socket error') self.transport.close() finally: out_socket.close() await super().write_eof() async def write_eof(self, chunk: bytes=b'') -> None: pass class FileResponse(StreamResponse): """A response object can be used to send files.""" def __init__(self, path: Union[str, pathlib.Path], 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) if isinstance(path, str): path = pathlib.Path(path) self._path = path self._chunk_size = chunk_size async def _sendfile_system(self, request: 'BaseRequest', fobj: IO[Any], count: int) -> AbstractStreamWriter: # Write count bytes of fobj to resp using # the os.sendfile system call. # # For details check # https://github.com/KeepSafe/aiohttp/issues/1177 # See https://github.com/KeepSafe/aiohttp/issues/958 for details # # request should be an aiohttp.web.Request instance. # fobj should be an open file object. # count should be an integer > 0. transport = request.transport assert transport is not None if (transport.get_extra_info("sslcontext") or transport.get_extra_info("socket") is None or self.compression): writer = await self._sendfile_fallback(request, fobj, count) else: writer = SendfileStreamWriter( request.protocol, request._loop, fobj, count ) request._payload_writer = writer await super().prepare(request) await writer.sendfile() return writer async def _sendfile_fallback(self, request: 'BaseRequest', fobj: IO[Any], count: int) -> AbstractStreamWriter: # Mimic the _sendfile_system() method, but without using the # os.sendfile() system call. This should be used on systems # that don't support the os.sendfile(). # To keep memory usage low,fobj is transferred in chunks # controlled by the constructor's chunk_size argument. writer = await super().prepare(request) assert writer is not None chunk_size = self._chunk_size loop = asyncio.get_event_loop() chunk = await loop.run_in_executor(None, fobj.read, 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 if hasattr(os, "sendfile") and not NOSENDFILE: # pragma: no cover _sendfile = _sendfile_system else: # pragma: no cover _sendfile = _sendfile_fallback async def prepare( self, request: 'BaseRequest' ) -> Optional[AbstractStreamWriter]: filepath = self._path gzip = False if 'gzip' in request.headers.get(hdrs.ACCEPT_ENCODING, ''): gzip_path = filepath.with_name(filepath.name + '.gz') if gzip_path.is_file(): filepath = gzip_path gzip = True loop = asyncio.get_event_loop() st = await loop.run_in_executor(None, filepath.stat) modsince = request.if_modified_since if modsince is not None and st.st_mtime <= modsince.timestamp(): self.set_status(HTTPNotModified.status_code) self._length_check = False # Delete any Content-Length headers provided by user. HTTP 304 # should always have empty response body return await super().prepare(request) unmodsince = request.if_unmodified_since if unmodsince is not None and st.st_mtime > unmodsince.timestamp(): self.set_status(HTTPPreconditionFailed.status_code) return await super().prepare(request) if hdrs.CONTENT_TYPE not in self.headers: ct, encoding = mimetypes.guess_type(str(filepath)) if not ct: ct = 'application/octet-stream' should_set_ct = True else: encoding = 'gzip' if gzip else None should_set_ct = False status = self._status file_size = st.st_size count = file_size start = None ifrange = request.if_range if ifrange is None or st.st_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 = 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] = 'bytes */{0}'.format( 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 or end 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] = 'bytes */{0}'.format( 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 should_set_ct: self.content_type = ct # type: ignore if encoding: self.headers[hdrs.CONTENT_ENCODING] = encoding if gzip: self.headers[hdrs.VARY] = hdrs.ACCEPT_ENCODING self.last_modified = st.st_mtime # type: ignore self.content_length = count self.headers[hdrs.ACCEPT_RANGES] = 'bytes' real_start = cast(int, start) if status == HTTPPartialContent.status_code: self.headers[hdrs.CONTENT_RANGE] = 'bytes {0}-{1}/{2}'.format( real_start, real_start + count - 1, file_size) fobj = await loop.run_in_executor(None, filepath.open, 'rb') if start: # be aware that start could be None or int=0 here. await loop.run_in_executor(None, fobj.seek, start) try: return await self._sendfile(request, fobj, count) finally: await loop.run_in_executor(None, fobj.close)