You should be redirected automatically to the target URL: " f'{display_location}. If' " not, click the link.\n", code, mimetype="text/html", ) response.headers["Location"] = location return response def append_slash_redirect(environ: "WSGIEnvironment", code: int = 308) -> "Response": """Redirect to the current URL with a slash appended. If the current URL is ``/user/42``, the redirect URL will be ``42/``. When joined to the current URL during response processing or by the browser, this will produce ``/user/42/``. The behavior is undefined if the path ends with a slash already. If called unconditionally on a URL, it may produce a redirect loop. :param environ: Use the path and query from this WSGI environment to produce the redirect URL. :param code: the status code for the redirect. .. versionchanged:: 2.1 Produce a relative URL that only modifies the last segment. Relevant when the current path has multiple segments. .. versionchanged:: 2.1 The default status code is 308 instead of 301. This preserves the request method and body. """ tail = environ["PATH_INFO"].rpartition("/")[2] if not tail: new_path = "./" else: new_path = f"{tail}/" query_string = environ.get("QUERY_STRING") if query_string: new_path = f"{new_path}?{query_string}" return redirect(new_path, code) def send_file( path_or_file: t.Union[os.PathLike, str, t.IO[bytes]], environ: "WSGIEnvironment", mimetype: t.Optional[str] = None, as_attachment: bool = False, download_name: t.Optional[str] = None, conditional: bool = True, etag: t.Union[bool, str] = True, last_modified: t.Optional[t.Union[datetime, int, float]] = None, max_age: t.Optional[ t.Union[int, t.Callable[[t.Optional[str]], t.Optional[int]]] ] = None, use_x_sendfile: bool = False, response_class: t.Optional[t.Type["Response"]] = None, _root_path: t.Optional[t.Union[os.PathLike, str]] = None, ) -> "Response": """Send the contents of a file to the client. The first argument can be a file path or a file-like object. Paths are preferred in most cases because Werkzeug can manage the file and get extra information from the path. Passing a file-like object requires that the file is opened in binary mode, and is mostly useful when building a file in memory with :class:`io.BytesIO`. Never pass file paths provided by a user. The path is assumed to be trusted, so a user could craft a path to access a file you didn't intend. Use :func:`send_from_directory` to safely serve user-provided paths. If the WSGI server sets a ``file_wrapper`` in ``environ``, it is used, otherwise Werkzeug's built-in wrapper is used. Alternatively, if the HTTP server supports ``X-Sendfile``, ``use_x_sendfile=True`` will tell the server to send the given path, which is much more efficient than reading it in Python. :param path_or_file: The path to the file to send, relative to the current working directory if a relative path is given. Alternatively, a file-like object opened in binary mode. Make sure the file pointer is seeked to the start of the data. :param environ: The WSGI environ for the current request. :param mimetype: The MIME type to send for the file. If not provided, it will try to detect it from the file name. :param as_attachment: Indicate to a browser that it should offer to save the file instead of displaying it. :param download_name: The default name browsers will use when saving the file. Defaults to the passed file name. :param conditional: Enable conditional and range responses based on request headers. Requires passing a file path and ``environ``. :param etag: Calculate an ETag for the file, which requires passing a file path. Can also be a string to use instead. :param last_modified: The last modified time to send for the file, in seconds. If not provided, it will try to detect it from the file path. :param max_age: How long the client should cache the file, in seconds. If set, ``Cache-Control`` will be ``public``, otherwise it will be ``no-cache`` to prefer conditional caching. :param use_x_sendfile: Set the ``X-Sendfile`` header to let the server to efficiently send the file. Requires support from the HTTP server. Requires passing a file path. :param response_class: Build the response using this class. Defaults to :class:`~werkzeug.wrappers.Response`. :param _root_path: Do not use. For internal use only. Use :func:`send_from_directory` to safely send files under a path. .. versionchanged:: 2.0.2 ``send_file`` only sets a detected ``Content-Encoding`` if ``as_attachment`` is disabled. .. versionadded:: 2.0 Adapted from Flask's implementation. .. versionchanged:: 2.0 ``download_name`` replaces Flask's ``attachment_filename`` parameter. If ``as_attachment=False``, it is passed with ``Content-Disposition: inline`` instead. .. versionchanged:: 2.0 ``max_age`` replaces Flask's ``cache_timeout`` parameter. ``conditional`` is enabled and ``max_age`` is not set by default. .. versionchanged:: 2.0 ``etag`` replaces Flask's ``add_etags`` parameter. It can be a string to use instead of generating one. .. versionchanged:: 2.0 If an encoding is returned when guessing ``mimetype`` from ``download_name``, set the ``Content-Encoding`` header. """ if response_class is None: from .wrappers import Response response_class = Response path: t.Optional[str] = None file: t.Optional[t.IO[bytes]] = None size: t.Optional[int] = None mtime: t.Optional[float] = None headers = Headers() if isinstance(path_or_file, (os.PathLike, str)) or hasattr( path_or_file, "__fspath__" ): path_or_file = t.cast(t.Union[os.PathLike, str], path_or_file) # Flask will pass app.root_path, allowing its send_file wrapper # to not have to deal with paths. if _root_path is not None: path = os.path.join(_root_path, path_or_file) else: path = os.path.abspath(path_or_file) stat = os.stat(path) size = stat.st_size mtime = stat.st_mtime else: file = path_or_file if download_name is None and path is not None: download_name = os.path.basename(path) if mimetype is None: if download_name is None: raise TypeError( "Unable to detect the MIME type because a file name is" " not available. Either set 'download_name', pass a" " path instead of a file, or set 'mimetype'." ) mimetype, encoding = mimetypes.guess_type(download_name) if mimetype is None: mimetype = "application/octet-stream" # Don't send encoding for attachments, it causes browsers to # save decompress tar.gz files. if encoding is not None and not as_attachment: headers.set("Content-Encoding", encoding) if download_name is not None: try: download_name.encode("ascii") except UnicodeEncodeError: simple = unicodedata.normalize("NFKD", download_name) simple = simple.encode("ascii", "ignore").decode("ascii") quoted = url_quote(download_name, safe="") names = {"filename": simple, "filename*": f"UTF-8''{quoted}"} else: names = {"filename": download_name} value = "attachment" if as_attachment else "inline" headers.set("Content-Disposition", value, **names) elif as_attachment: raise TypeError( "No name provided for attachment. Either set" " 'download_name' or pass a path instead of a file." ) if use_x_sendfile and path is not None: headers["X-Sendfile"] = path data = None else: if file is None: file = open(path, "rb") # type: ignore elif isinstance(file, io.BytesIO): size = file.getbuffer().nbytes elif isinstance(file, io.TextIOBase): raise ValueError("Files must be opened in binary mode or use BytesIO.") data = wrap_file(environ, file) rv = response_class( data, mimetype=mimetype, headers=headers, direct_passthrough=True ) if size is not None: rv.content_length = size if last_modified is not None: rv.last_modified = last_modified # type: ignore elif mtime is not None: rv.last_modified = mtime # type: ignore rv.cache_control.no_cache = True # Flask will pass app.get_send_file_max_age, allowing its send_file # wrapper to not have to deal with paths. if callable(max_age): max_age = max_age(path) if max_age is not None: if max_age > 0: rv.cache_control.no_cache = None rv.cache_control.public = True rv.cache_control.max_age = max_age rv.expires = int(time() + max_age) # type: ignore if isinstance(etag, str): rv.set_etag(etag) elif etag and path is not None: check = adler32(path.encode("utf-8")) & 0xFFFFFFFF rv.set_etag(f"{mtime}-{size}-{check}") if conditional: try: rv = rv.make_conditional(environ, accept_ranges=True, complete_length=size) except RequestedRangeNotSatisfiable: if file is not None: file.close() raise # Some x-sendfile implementations incorrectly ignore the 304 # status code and send the file anyway. if rv.status_code == 304: rv.headers.pop("x-sendfile", None) return rv def send_from_directory( directory: t.Union[os.PathLike, str], path: t.Union[os.PathLike, str], environ: "WSGIEnvironment", **kwargs: t.Any, ) -> "Response": """Send a file from within a directory using :func:`send_file`. This is a secure way to serve files from a folder, such as static files or uploads. Uses :func:`~werkzeug.security.safe_join` to ensure the path coming from the client is not maliciously crafted to point outside the specified directory. If the final path does not point to an existing regular file, returns a 404 :exc:`~werkzeug.exceptions.NotFound` error. :param directory: The directory that ``path`` must be located under. This *must not* be a value provided by the client, otherwise it becomes insecure. :param path: The path to the file to send, relative to ``directory``. This is the part of the path provided by the client, which is checked for security. :param environ: The WSGI environ for the current request. :param kwargs: Arguments to pass to :func:`send_file`. .. versionadded:: 2.0 Adapted from Flask's implementation. """ path = safe_join(os.fspath(directory), os.fspath(path)) if path is None: raise NotFound() # Flask will pass app.root_path, allowing its send_from_directory # wrapper to not have to deal with paths. if "_root_path" in kwargs: path = os.path.join(kwargs["_root_path"], path) try: if not os.path.isfile(path): raise NotFound() except ValueError: # path contains null byte on Python < 3.8 raise NotFound() from None return send_file(path, environ, **kwargs) def import_string(import_name: str, silent: bool = False) -> t.Any: """Imports an object based on a string. This is useful if you want to use import paths as endpoints or something similar. An import path can be specified either in dotted notation (``xml.sax.saxutils.escape``) or with a colon as object delimiter (``xml.sax.saxutils:escape``). If `silent` is True the return value will be `None` if the import fails. :param import_name: the dotted name for the object to import. :param silent: if set to `True` import errors are ignored and `None` is returned instead. :return: imported object """ import_name = import_name.replace(":", ".") try: try: __import__(import_name) except ImportError: if "." not in import_name: raise else: return sys.modules[import_name] module_name, obj_name = import_name.rsplit(".", 1) module = __import__(module_name, globals(), locals(), [obj_name]) try: return getattr(module, obj_name) except AttributeError as e: raise ImportError(e) from None except ImportError as e: if not silent: raise ImportStringError(import_name, e).with_traceback( sys.exc_info()[2] ) from None return None def find_modules( import_path: str, include_packages: bool = False, recursive: bool = False ) -> t.Iterator[str]: """Finds all the modules below a package. This can be useful to automatically import all views / controllers so that their metaclasses / function decorators have a chance to register themselves on the application. Packages are not returned unless `include_packages` is `True`. This can also recursively list modules but in that case it will import all the packages to get the correct load path of that module. :param import_path: the dotted name for the package to find child modules. :param include_packages: set to `True` if packages should be returned, too. :param recursive: set to `True` if recursion should happen. :return: generator """ module = import_string(import_path) path = getattr(module, "__path__", None) if path is None: raise ValueError(f"{import_path!r} is not a package") basename = f"{module.__name__}." for _importer, modname, ispkg in pkgutil.iter_modules(path): modname = basename + modname if ispkg: if include_packages: yield modname if recursive: yield from find_modules(modname, include_packages, True) else: yield modname class ImportStringError(ImportError): """Provides information about a failed :func:`import_string` attempt.""" #: String in dotted notation that failed to be imported. import_name: str #: Wrapped exception. exception: BaseException def __init__(self, import_name: str, exception: BaseException) -> None: self.import_name = import_name self.exception = exception msg = import_name name = "" tracked = [] for part in import_name.replace(":", ".").split("."): name = f"{name}.{part}" if name else part imported = import_string(name, silent=True) if imported: tracked.append((name, getattr(imported, "__file__", None))) else: track = [f"- {n!r} found in {i!r}." for n, i in tracked] track.append(f"- {name!r} not found.") track_str = "\n".join(track) msg = ( f"import_string() failed for {import_name!r}. Possible reasons" f" are:\n\n" "- missing __init__.py in a package;\n" "- package or module path not included in sys.path;\n" "- duplicated package or module name taking precedence in" " sys.path;\n" "- missing module, class, function or variable;\n\n" f"Debugged import:\n\n{track_str}\n\n" f"Original exception:\n\n{type(exception).__name__}: {exception}" ) break super().__init__(msg) def __repr__(self) -> str: return f"<{type(self).__name__}({self.import_name!r}, {self.exception!r})>"