falcon.request 源代码

# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#    http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

"""Request class."""

from datetime import datetime
from io import BytesIO
from uuid import UUID

from falcon import errors
from falcon import request_helpers as helpers
from falcon import util
from falcon.constants import _UNSET
from falcon.constants import DEFAULT_MEDIA_TYPE
from falcon.constants import MEDIA_JSON
from falcon.forwarded import _parse_forwarded_header

# TODO: remove import in falcon 4
from falcon.forwarded import Forwarded  # NOQA
from falcon.media import Handlers
from falcon.media.json import _DEFAULT_JSON_HANDLER
from falcon.stream import BoundedStream
from falcon.util import structures
from falcon.util.misc import isascii
from falcon.util.uri import parse_host
from falcon.util.uri import parse_query_string
from falcon.vendor import mimeparse

DEFAULT_ERROR_LOG_FORMAT = '{0:%Y-%m-%d %H:%M:%S} [FALCON] [ERROR] {1} {2}{3} => '

TRUE_STRINGS = frozenset(['true', 'True', 't', 'yes', 'y', '1', 'on'])
FALSE_STRINGS = frozenset(['false', 'False', 'f', 'no', 'n', '0', 'off'])
WSGI_CONTENT_HEADERS = frozenset(['CONTENT_TYPE', 'CONTENT_LENGTH'])

# PERF(kgriffs): Avoid an extra namespace lookup when using these functions
strptime = datetime.strptime
now = datetime.now


[文档]class Request: """Represents a client's HTTP request. Note: `Request` is not meant to be instantiated directly by responders. Args: env (dict): A WSGI environment dict passed in from the server. See also PEP-3333. Keyword Arguments: options (dict): Set of global options passed from the App handler. Attributes: env (dict): Reference to the WSGI environ ``dict`` passed in from the server. (See also PEP-3333.) context (object): Empty object to hold any data (in its attributes) about the request which is specific to your app (e.g. session object). Falcon itself will not interact with this attribute after it has been initialized. Note: **New in 2.0:** The default `context_type` (see below) was changed from :class:`dict` to a bare class; the preferred way to pass request-specific data is now to set attributes directly on the `context` object. For example:: req.context.role = 'trial' req.context.user = 'guest' context_type (class): Class variable that determines the factory or type to use for initializing the `context` attribute. By default, the framework will instantiate bare objects (instances of the bare :class:`falcon.Context` class). However, you may override this behavior by creating a custom child class of ``falcon.Request``, and then passing that new class to `falcon.App()` by way of the latter's `request_type` parameter. Note: When overriding `context_type` with a factory function (as opposed to a class), the function is called like a method of the current Request instance. Therefore the first argument is the Request instance itself (self). scheme (str): URL scheme used for the request. Either 'http' or 'https'. Note: If the request was proxied, the scheme may not match what was originally requested by the client. :py:attr:`forwarded_scheme` can be used, instead, to handle such cases. forwarded_scheme (str): Original URL scheme requested by the user agent, if the request was proxied. Typical values are 'http' or 'https'. The following request headers are checked, in order of preference, to determine the forwarded scheme: - ``Forwarded`` - ``X-Forwarded-For`` If none of these headers are available, or if the Forwarded header is available but does not contain a "proto" parameter in the first hop, the value of :attr:`scheme` is returned instead. (See also: RFC 7239, Section 1) method (str): HTTP method requested (e.g., 'GET', 'POST', etc.) host (str): Host request header field forwarded_host (str): Original host request header as received by the first proxy in front of the application server. The following request headers are checked, in order of preference, to determine the forwarded scheme: - ``Forwarded`` - ``X-Forwarded-Host`` If none of the above headers are available, or if the Forwarded header is available but the "host" parameter is not included in the first hop, the value of :attr:`host` is returned instead. Note: Reverse proxies are often configured to set the Host header directly to the one that was originally requested by the user agent; in that case, using :attr:`host` is sufficient. (See also: RFC 7239, Section 4) port (int): Port used for the request. If the Host header is present in the request, but does not specify a port, the default one for the given schema is returned (80 for HTTP and 443 for HTTPS). If the request does not include a Host header, the listening port for the WSGI server is returned instead. netloc (str): Returns the "host:port" portion of the request URL. The port may be omitted if it is the default one for the URL's schema (80 for HTTP and 443 for HTTPS). subdomain (str): Leftmost (i.e., most specific) subdomain from the hostname. If only a single domain name is given, `subdomain` will be ``None``. Note: If the hostname in the request is an IP address, the value for `subdomain` is undefined. root_path (str): The initial portion of the request URI's path that corresponds to the application object, so that the application knows its virtual "location". This may be an empty string, if the application corresponds to the "root" of the server. (Corresponds to the "SCRIPT_NAME" environ variable defined by PEP-3333.) app (str): Deprecated alias for :attr:`root_path`. uri (str): The fully-qualified URI for the request. url (str): Alias for :attr:`uri`. forwarded_uri (str): Original URI for proxied requests. Uses :attr:`forwarded_scheme` and :attr:`forwarded_host` in order to reconstruct the original URI requested by the user agent. relative_uri (str): The path and query string portion of the request URI, omitting the scheme and host. prefix (str): The prefix of the request URI, including scheme, host, and WSGI app (if any). forwarded_prefix (str): The prefix of the original URI for proxied requests. Uses :attr:`forwarded_scheme` and :attr:`forwarded_host` in order to reconstruct the original URI. path (str): Path portion of the request URI (not including query string). Warning: If this attribute is to be used by the app for any upstream requests, any non URL-safe characters in the path must be URL encoded back before making the request. Note: ``req.path`` may be set to a new value by a ``process_request()`` middleware method in order to influence routing. If the original request path was URL encoded, it will be decoded before being returned by this attribute. query_string (str): Query string portion of the request URI, without the preceding '?' character. uri_template (str): The template for the route that was matched for this request. May be ``None`` if the request has not yet been routed, as would be the case for ``process_request()`` middleware methods. May also be ``None`` if your app uses a custom routing engine and the engine does not provide the URI template when resolving a route. remote_addr(str): IP address of the closest client or proxy to the WSGI server. This property is determined by the value of ``REMOTE_ADDR`` in the WSGI environment dict. Since this address is not derived from an HTTP header, clients and proxies can not forge it. Note: If your application is behind one or more reverse proxies, you can use :py:attr:`~.access_route` to retrieve the real IP address of the client. access_route(list): IP address of the original client, as well as any known addresses of proxies fronting the WSGI server. The following request headers are checked, in order of preference, to determine the addresses: - ``Forwarded`` - ``X-Forwarded-For`` - ``X-Real-IP`` If none of these headers are available, the value of :py:attr:`~.remote_addr` is used instead. Note: Per `RFC 7239`_, the access route may contain "unknown" and obfuscated identifiers, in addition to IPv4 and IPv6 addresses .. _RFC 7239: https://tools.ietf.org/html/rfc7239 Warning: Headers can be forged by any client or proxy. Use this property with caution and validate all values before using them. Do not rely on the access route to authorize requests. forwarded (list): Value of the Forwarded header, as a parsed list of :class:`falcon.Forwarded` objects, or ``None`` if the header is missing. If the header value is malformed, Falcon will make a best effort to parse what it can. (See also: RFC 7239, Section 4) date (datetime): Value of the Date header, converted to a ``datetime`` instance. The header value is assumed to conform to RFC 1123. auth (str): Value of the Authorization header, or ``None`` if the header is missing. user_agent (str): Value of the User-Agent header, or ``None`` if the header is missing. referer (str): Value of the Referer header, or ``None`` if the header is missing. accept (str): Value of the Accept header, or ``'*/*'`` if the header is missing. client_accepts_json (bool): ``True`` if the Accept header indicates that the client is willing to receive JSON, otherwise ``False``. client_accepts_msgpack (bool): ``True`` if the Accept header indicates that the client is willing to receive MessagePack, otherwise ``False``. client_accepts_xml (bool): ``True`` if the Accept header indicates that the client is willing to receive XML, otherwise ``False``. cookies (dict): A dict of name/value cookie pairs. The returned object should be treated as read-only to avoid unintended side-effects. If a cookie appears more than once in the request, only the first value encountered will be made available here. See also: :meth:`~falcon.Request.get_cookie_values` content_type (str): Value of the Content-Type header, or ``None`` if the header is missing. content_length (int): Value of the Content-Length header converted to an ``int``, or ``None`` if the header is missing. stream: File-like input object for reading the body of the request, if any. This object provides direct access to the server's data stream and is non-seekable. In order to avoid unintended side effects, and to provide maximum flexibility to the application, Falcon itself does not buffer or spool the data in any way. Since this object is provided by the WSGI server itself, rather than by Falcon, it may behave differently depending on how you host your app. For example, attempting to read more bytes than are expected (as determined by the Content-Length header) may or may not block indefinitely. It's a good idea to test your WSGI server to find out how it behaves. This can be particularly problematic when a request body is expected, but none is given. In this case, the following call blocks under certain WSGI servers:: # Blocks if Content-Length is 0 data = req.stream.read() The workaround is fairly straightforward, if verbose:: # If Content-Length happens to be 0, or the header is # missing altogether, this will not block. data = req.stream.read(req.content_length or 0) Alternatively, when passing the stream directly to a consumer, it may be necessary to branch off the value of the Content-Length header:: if req.content_length: doc = json.load(req.stream) For a slight performance cost, you may instead wish to use :py:attr:`bounded_stream`, which wraps the native WSGI input object to normalize its behavior. Note: If an HTML form is POSTed to the API using the *application/x-www-form-urlencoded* media type, and the :py:attr:`~.RequestOptions.auto_parse_form_urlencoded` option is set, the framework will consume `stream` in order to parse the parameters and merge them into the query string parameters. In this case, the stream will be left at EOF. bounded_stream: File-like wrapper around `stream` to normalize certain differences between the native input objects employed by different WSGI servers. In particular, `bounded_stream` is aware of the expected Content-Length of the body, and will never block on out-of-bounds reads, assuming the client does not stall while transmitting the data to the server. For example, the following will not block when Content-Length is 0 or the header is missing altogether:: data = req.bounded_stream.read() This is also safe:: doc = json.load(req.bounded_stream) media (object): Property that acts as an alias for :meth:`~.get_media`. This alias provides backwards-compatibility for apps that were built for versions of the framework prior to 3.0:: # Equivalent to: deserialized_media = req.get_media() deserialized_media = req.media expect (str): Value of the Expect header, or ``None`` if the header is missing. range (tuple of int): A 2-member ``tuple`` parsed from the value of the Range header, or ``None`` if the header is missing. The two members correspond to the first and last byte positions of the requested resource, inclusive. Negative indices indicate offset from the end of the resource, where -1 is the last byte, -2 is the second-to-last byte, and so forth. Only continuous ranges are supported (e.g., "bytes=0-0,-1" would result in an HTTPBadRequest exception when the attribute is accessed.) range_unit (str): Unit of the range parsed from the value of the Range header, or ``None`` if the header is missing if_match (list): Value of the If-Match header, as a parsed list of :class:`falcon.ETag` objects or ``None`` if the header is missing or its value is blank. This property provides a list of all ``entity-tags`` in the header, both strong and weak, in the same order as listed in the header. (See also: RFC 7232, Section 3.1) if_none_match (list): Value of the If-None-Match header, as a parsed list of :class:`falcon.ETag` objects or ``None`` if the header is missing or its value is blank. This property provides a list of all ``entity-tags`` in the header, both strong and weak, in the same order as listed in the header. (See also: RFC 7232, Section 3.2) if_modified_since (datetime): Value of the If-Modified-Since header, or ``None`` if the header is missing. if_unmodified_since (datetime): Value of the If-Unmodified-Since header, or ``None`` if the header is missing. if_range (str): Value of the If-Range header, or ``None`` if the header is missing. headers (dict): Raw HTTP headers from the request with dash-separated names normalized to uppercase. Note: This property differs from the ASGI version of ``Request.headers`` in that the latter returns *lowercase* names. Middleware, such as tracing and logging components, that need to be compatible with both WSGI and ASGI apps should use :attr:`headers_lower` instead. Warning: Parsing all the headers to create this dict is done the first time this attribute is accessed, and the returned object should be treated as read-only. Note that this parsing can be costly, so unless you need all the headers in this format, you should instead use the ``get_header()`` method or one of the convenience attributes to get a value for a specific header. headers_lower (dict): Same as :attr:`headers` except header names are normalized to lowercase. params (dict): The mapping of request query parameter names to their values. Where the parameter appears multiple times in the query string, the value mapped to that parameter key will be a list of all the values in the order seen. options (dict): Set of global options passed from the App handler. """ __slots__ = ( '__dict__', '_bounded_stream', '_cached_access_route', '_cached_forwarded', '_cached_forwarded_prefix', '_cached_forwarded_uri', '_cached_headers', '_cached_headers_lower', '_cached_prefix', '_cached_relative_uri', '_cached_uri', '_params', '_wsgierrors', 'content_type', 'context', 'env', 'method', 'options', 'path', 'query_string', 'stream', 'uri_template', '_media', '_media_error', 'is_websocket', ) _cookies = None _cookies_collapsed = None _cached_if_match = None _cached_if_none_match = None # Child classes may override this context_type = structures.Context _wsgi_input_type_known = False def __init__(self, env, options=None): self.is_websocket = False self.env = env self.options = options if options else RequestOptions() self._wsgierrors = env['wsgi.errors'] self.method = env['REQUEST_METHOD'] self.uri_template = None self._media = _UNSET self._media_error = None # NOTE(kgriffs): PEP 3333 specifies that PATH_INFO may be the # empty string, so normalize it in that case. path = env['PATH_INFO'] or '/' # PEP 3333 specifies that the PATH_INFO variable is always # "bytes tunneled as latin-1" and must be encoded back. # # NOTE(kgriffs): The decoded path may contain UTF-8 characters. # But according to the WSGI spec, no strings can contain chars # outside ISO-8859-1. Therefore, to reconcile the URI # encoding standard that allows UTF-8 with the WSGI spec # that does not, WSGI servers tunnel the string via # ISO-8859-1, e.g.: # # tunnelled_path = path.encode('utf-8').decode('iso-8859-1') # perf(vytas): Only decode the tunnelled path in case it is not ASCII. # For ASCII-strings, the below decoding chain is a no-op. if not isascii(path): path = path.encode('iso-8859-1').decode('utf-8', 'replace') if ( self.options.strip_url_path_trailing_slash and len(path) != 1 and path.endswith('/') ): self.path = path[:-1] else: self.path = path # PERF(ueg1990): try/catch cheaper and faster (and more Pythonic) try: self.query_string = env['QUERY_STRING'] except KeyError: self.query_string = '' self._params = {} else: if self.query_string: self._params = parse_query_string( self.query_string, keep_blank=self.options.keep_blank_qs_values, csv=self.options.auto_parse_qs_csv, ) else: self._params = {} self._cached_access_route = None self._cached_forwarded = None self._cached_forwarded_prefix = None self._cached_forwarded_uri = None self._cached_headers = None self._cached_headers_lower = None self._cached_prefix = None self._cached_relative_uri = None self._cached_uri = None try: self.content_type = self.env['CONTENT_TYPE'] except KeyError: self.content_type = None self.stream = env['wsgi.input'] self._bounded_stream = None # Lazy wrapping # PERF(kgriffs): Technically, we should spend a few more # cycles and parse the content type for real, but # this heuristic will work virtually all the time. if ( self.options.auto_parse_form_urlencoded and self.content_type is not None and 'application/x-www-form-urlencoded' in self.content_type and # NOTE(kgriffs): Within HTTP, a payload for a GET or HEAD # request has no defined semantics, so we don't expect a # body in those cases. We would normally not expect a body # for OPTIONS either, but RFC 7231 does allow for it. self.method not in ('GET', 'HEAD') ): self._parse_form_urlencoded() self.context = self.context_type() def __repr__(self): return '<%s: %s %r>' % (self.__class__.__name__, self.method, self.url) # ------------------------------------------------------------------------ # Properties # ------------------------------------------------------------------------ user_agent = helpers.header_property('HTTP_USER_AGENT') auth = helpers.header_property('HTTP_AUTHORIZATION') expect = helpers.header_property('HTTP_EXPECT') if_range = helpers.header_property('HTTP_IF_RANGE') referer = helpers.header_property('HTTP_REFERER') @property def forwarded(self): # PERF(kgriffs): We could DRY up this memoization pattern using # a decorator, but that would incur additional overhead without # resorting to some trickery to rewrite the body of the method # itself (vs. simply wrapping it with some memoization logic). # At some point we might look into this but I don't think # it's worth it right now. if self._cached_forwarded is None: forwarded = self.get_header('Forwarded') if forwarded is None: return None self._cached_forwarded = _parse_forwarded_header(forwarded) return self._cached_forwarded @property def client_accepts_json(self): return self.client_accepts('application/json') @property def client_accepts_msgpack(self): return self.client_accepts('application/x-msgpack') or self.client_accepts( 'application/msgpack' ) @property def client_accepts_xml(self): return self.client_accepts('application/xml') @property def accept(self): # NOTE(kgriffs): Per RFC, a missing accept header is # equivalent to '*/*' try: return self.env['HTTP_ACCEPT'] or '*/*' except KeyError: return '*/*' @property def content_length(self): try: value = self.env['CONTENT_LENGTH'] except KeyError: return None # NOTE(kgriffs): Normalize an empty value to behave as if # the header were not included; wsgiref, at least, inserts # an empty CONTENT_LENGTH value if the request does not # set the header. Gunicorn and uWSGI do not do this, but # others might if they are trying to match wsgiref's # behavior too closely. if not value: return None try: value_as_int = int(value) except ValueError: msg = 'The value of the header must be a number.' raise errors.HTTPInvalidHeader(msg, 'Content-Length') if value_as_int < 0: msg = 'The value of the header must be a positive number.' raise errors.HTTPInvalidHeader(msg, 'Content-Length') return value_as_int @property def bounded_stream(self): if self._bounded_stream is None: self._bounded_stream = self._get_wrapped_wsgi_input() return self._bounded_stream @property def date(self): return self.get_header_as_datetime('Date') @property def if_match(self): # TODO(kgriffs): It may make sense at some point to create a # header property generator that DRY's up the memoization # pattern for us. # PERF(kgriffs): It probably isn't worth it to set # self._cached_if_match to a special type/object to distinguish # between the variable being unset and the header not being # present in the request. The reason is that if the app # gets a None back on the first reference to property, it # probably isn't going to access the property again (TBD). if self._cached_if_match is None: header_value = self.env.get('HTTP_IF_MATCH') if header_value: self._cached_if_match = helpers._parse_etags(header_value) return self._cached_if_match @property def if_none_match(self): if self._cached_if_none_match is None: header_value = self.env.get('HTTP_IF_NONE_MATCH') if header_value: self._cached_if_none_match = helpers._parse_etags(header_value) return self._cached_if_none_match @property def if_modified_since(self): return self.get_header_as_datetime('If-Modified-Since') @property def if_unmodified_since(self): return self.get_header_as_datetime('If-Unmodified-Since') @property def range(self): value = self.get_header('Range') if value is None: return None if '=' in value: unit, sep, req_range = value.partition('=') else: msg = "The value must be prefixed with a range unit, e.g. 'bytes='" raise errors.HTTPInvalidHeader(msg, 'Range') if ',' in req_range: msg = 'The value must be a continuous range.' raise errors.HTTPInvalidHeader(msg, 'Range') try: first, sep, last = req_range.partition('-') if not sep: raise ValueError() if first and last: first, last = (int(first), int(last)) if last < first: raise ValueError() elif first: first, last = (int(first), -1) elif last: first, last = (-int(last), -1) if first >= 0: raise ValueError() else: msg = 'The range offsets are missing.' raise errors.HTTPInvalidHeader(msg, 'Range') return first, last except ValueError: href = 'https://tools.ietf.org/html/rfc7233' href_text = 'HTTP/1.1 Range Requests' msg = 'It must be a range formatted according to RFC 7233.' raise errors.HTTPInvalidHeader(msg, 'Range', href=href, href_text=href_text) @property def range_unit(self): value = self.get_header('Range') if value is None: return None if value and '=' in value: unit, sep, req_range = value.partition('=') return unit else: msg = "The value must be prefixed with a range unit, e.g. 'bytes='" raise errors.HTTPInvalidHeader(msg, 'Range') @property def root_path(self): # PERF(kgriffs): try..except is faster than get() assuming that # we normally expect the key to exist. Even though PEP-3333 # allows WSGI servers to omit the key when the value is an # empty string, uwsgi, gunicorn, waitress, and wsgiref all # include it even in that case. try: return self.env['SCRIPT_NAME'] except KeyError: return '' app = root_path @property def scheme(self): return self.env['wsgi.url_scheme'] @property def forwarded_scheme(self): # PERF(kgriffs): Since the Forwarded header is still relatively # new, we expect X-Forwarded-Proto to be more common, so # try to avoid calling self.forwarded if we can, since it uses a # try...catch that will usually result in a relatively expensive # raised exception. if 'HTTP_FORWARDED' in self.env: forwarded = self.forwarded if forwarded: # Use first hop, fall back on own scheme scheme = forwarded[0].scheme or self.scheme else: scheme = self.scheme else: # PERF(kgriffs): This call should normally succeed, so # just go for it without wasting time checking it # first. Note also that the indexing operator is # slightly faster than using get(). try: scheme = self.env['HTTP_X_FORWARDED_PROTO'].lower() except KeyError: scheme = self.env['wsgi.url_scheme'] return scheme @property def uri(self): if self._cached_uri is None: # PERF: For small numbers of items, '+' is faster # than ''.join(...). Concatenation is also generally # faster than formatting. value = self.scheme + '://' + self.netloc + self.relative_uri self._cached_uri = value return self._cached_uri url = uri @property def forwarded_uri(self): if self._cached_forwarded_uri is None: # PERF: For small numbers of items, '+' is faster # than ''.join(...). Concatenation is also generally # faster than formatting. value = ( self.forwarded_scheme + '://' + self.forwarded_host + self.relative_uri ) self._cached_forwarded_uri = value return self._cached_forwarded_uri @property def relative_uri(self): if self._cached_relative_uri is None: if self.query_string: self._cached_relative_uri = ( self.app + self.path + '?' + self.query_string ) else: self._cached_relative_uri = self.app + self.path return self._cached_relative_uri @property def prefix(self): if self._cached_prefix is None: self._cached_prefix = self.scheme + '://' + self.netloc + self.app return self._cached_prefix @property def forwarded_prefix(self): if self._cached_forwarded_prefix is None: self._cached_forwarded_prefix = ( self.forwarded_scheme + '://' + self.forwarded_host + self.app ) return self._cached_forwarded_prefix @property def host(self): try: # NOTE(kgriffs): Prefer the host header; the web server # isn't supposed to mess with it, so it should be what # the client actually sent. host_header = self.env['HTTP_HOST'] host, port = parse_host(host_header) except KeyError: # PERF(kgriffs): According to PEP-3333, this header # will always be present. host = self.env['SERVER_NAME'] return host @property def forwarded_host(self): # PERF(kgriffs): Since the Forwarded header is still relatively # new, we expect X-Forwarded-Host to be more common, so # try to avoid calling self.forwarded if we can, since it uses a # try...catch that will usually result in a relatively expensive # raised exception. if 'HTTP_FORWARDED' in self.env: forwarded = self.forwarded if forwarded: # Use first hop, fall back on self host = forwarded[0].host or self.netloc else: host = self.netloc else: # PERF(kgriffs): This call should normally succeed, assuming # that the caller is expecting a forwarded header, so # just go for it without wasting time checking it # first. try: host = self.env['HTTP_X_FORWARDED_HOST'] except KeyError: host = self.netloc return host @property def subdomain(self): # PERF(kgriffs): .partition is slightly faster than .split subdomain, sep, remainder = self.host.partition('.') return subdomain if sep else None @property def headers(self): if self._cached_headers is None: headers = self._cached_headers = {} env = self.env for name, value in env.items(): if name.startswith('HTTP_'): # NOTE(kgriffs): Don't take the time to fix the case # since headers are supposed to be case-insensitive # anyway. headers[name[5:].replace('_', '-')] = value elif name in WSGI_CONTENT_HEADERS: headers[name.replace('_', '-')] = value return self._cached_headers @property def headers_lower(self): if self._cached_headers_lower is None: self._cached_headers_lower = { key.lower(): value for key, value in self.headers.items() } return self._cached_headers_lower @property def params(self): return self._params @property def cookies(self): if self._cookies_collapsed is None: if self._cookies is None: header_value = self.get_header('Cookie') if header_value: self._cookies = helpers.parse_cookie_header(header_value) else: self._cookies = {} self._cookies_collapsed = {n: v[0] for n, v in self._cookies.items()} return self._cookies_collapsed @property def access_route(self): if self._cached_access_route is None: # NOTE(kgriffs): Try different headers in order of # preference; if none are found, fall back to REMOTE_ADDR. # # If one of these headers is present, but its value is # malformed such that we end up with an empty list, or # a non-empty list containing malformed values, go ahead # and return the results as-is. The alternative would be # to fall back to another header or to REMOTE_ADDR, but # that only masks the problem; the operator needs to be # aware that an upstream proxy is malfunctioning. if 'HTTP_FORWARDED' in self.env: self._cached_access_route = [] for hop in self.forwarded: if hop.src is not None: host, __ = parse_host(hop.src) self._cached_access_route.append(host) elif 'HTTP_X_FORWARDED_FOR' in self.env: addresses = self.env['HTTP_X_FORWARDED_FOR'].split(',') self._cached_access_route = [ip.strip() for ip in addresses] elif 'HTTP_X_REAL_IP' in self.env: self._cached_access_route = [self.env['HTTP_X_REAL_IP']] if self._cached_access_route: if self._cached_access_route[-1] != self.remote_addr: self._cached_access_route.append(self.remote_addr) else: self._cached_access_route = [self.remote_addr] return self._cached_access_route @property def remote_addr(self): try: value = self.env['REMOTE_ADDR'] except KeyError: value = '127.0.0.1' return value @property def port(self): try: host_header = self.env['HTTP_HOST'] default_port = 80 if self.env['wsgi.url_scheme'] == 'http' else 443 host, port = parse_host(host_header, default_port=default_port) except KeyError: # NOTE(kgriffs): Normalize to an int, since that is the type # returned by parse_host(). # # NOTE(kgriffs): In the case that SERVER_PORT was used, # PEP-3333 requires that the port never be an empty string. port = int(self.env['SERVER_PORT']) return port @property def netloc(self): env = self.env # NOTE(kgriffs): According to PEP-3333 we should first # try to use the Host header if present. # # PERF(kgriffs): try..except is faster than get() when we # expect the key to be present most of the time. try: netloc_value = env['HTTP_HOST'] except KeyError: netloc_value = env['SERVER_NAME'] port = env['SERVER_PORT'] if self.scheme == 'https': if port != '443': netloc_value += ':' + port else: if port != '80': netloc_value += ':' + port return netloc_value
[文档] def get_media(self, default_when_empty=_UNSET): """Return a deserialized form of the request stream. The first time this method is called, the request stream will be deserialized using the Content-Type header as well as the media-type handlers configured via :class:`falcon.RequestOptions`. The result will be cached and returned in subsequent calls:: deserialized_media = req.get_media() If the matched media handler raises an error while attempting to deserialize the request body, the exception will propagate up to the caller. See also :ref:`media` for more information regarding media handling. Note: When ``get_media`` is called on a request with an empty body, Falcon will let the media handler try to deserialize the body and will return the value returned by the handler or propagate the exception raised by it. To instead return a different value in case of an exception by the handler, specify the argument ``default_when_empty``. Warning: This operation will consume the request stream the first time it's called and cache the results. Follow-up calls will just retrieve a cached version of the object. Args: default_when_empty: Fallback value to return when there is no body in the request and the media handler raises an error (like in the case of the default JSON media handler). By default, Falcon uses the value returned by the media handler or propagates the raised exception, if any. This value is not cached, and will be used only for the current call. Returns: media (object): The deserialized media representation. """ if self._media is not _UNSET: return self._media if self._media_error is not None: if default_when_empty is not _UNSET and isinstance( self._media_error, errors.MediaNotFoundError ): return default_when_empty raise self._media_error handler, _, _ = self.options.media_handlers._resolve( self.content_type, self.options.default_media_type ) try: self._media = handler.deserialize( self.bounded_stream, self.content_type, self.content_length ) except errors.MediaNotFoundError as err: self._media_error = err if default_when_empty is not _UNSET: return default_when_empty raise except Exception as err: self._media_error = err raise finally: if handler.exhaust_stream: self.bounded_stream.exhaust() return self._media
media = property(get_media) # ------------------------------------------------------------------------ # Methods # ------------------------------------------------------------------------
[文档] def client_accepts(self, media_type): """Determine whether or not the client accepts a given media type. Args: media_type (str): An Internet media type to check. Returns: bool: ``True`` if the client has indicated in the Accept header that it accepts the specified media type. Otherwise, returns ``False``. """ accept = self.accept # PERF(kgriffs): Usually the following will be true, so # try it first. if (accept == media_type) or (accept == '*/*'): return True # Fall back to full-blown parsing try: return mimeparse.quality(media_type, accept) != 0.0 except ValueError: return False
[文档] def client_prefers(self, media_types): """Return the client's preferred media type, given several choices. Args: media_types (iterable of str): One or more Internet media types from which to choose the client's preferred type. This value **must** be an iterable collection of strings. Returns: str: The client's preferred media type, based on the Accept header. Returns ``None`` if the client does not accept any of the given types. """ try: # NOTE(kgriffs): best_match will return '' if no match is found preferred_type = mimeparse.best_match(media_types, self.accept) except ValueError: # Value for the accept header was not formatted correctly preferred_type = '' return preferred_type if preferred_type else None
[文档] def get_header(self, name, required=False, default=None): """Retrieve the raw string value for the given header. Args: name (str): Header name, case-insensitive (e.g., 'Content-Type') Keyword Args: required (bool): Set to ``True`` to raise ``HTTPBadRequest`` instead of returning gracefully when the header is not found (default ``False``). default (any): Value to return if the header is not found (default ``None``). Returns: str: The value of the specified header if it exists, or the default value if the header is not found and is not required. Raises: HTTPBadRequest: The header was not found in the request, but it was required. """ wsgi_name = name.upper().replace('-', '_') # Use try..except to optimize for the header existing in most cases try: # Don't take the time to cache beforehand, using HTTP naming. # This will be faster, assuming that most headers are looked # up only once, and not all headers will be requested. return self.env['HTTP_' + wsgi_name] except KeyError: # NOTE(kgriffs): There are a couple headers that do not # use the HTTP prefix in the env, so try those. We expect # people to usually just use the relevant helper properties # to access these instead of .get_header. if wsgi_name in WSGI_CONTENT_HEADERS: try: return self.env[wsgi_name] except KeyError: pass if not required: return default raise errors.HTTPMissingHeader(name)
[文档] def get_header_as_int(self, header, required=False): """Retrieve the int value for the given header. Args: name (str): Header name, case-insensitive (e.g., 'Content-Length') Keyword Args: required (bool): Set to ``True`` to raise ``HTTPBadRequest`` instead of returning gracefully when the header is not found (default ``False``). Returns: int: The value of the specified header if it exists, or ``None`` if the header is not found and is not required. Raises: HTTPBadRequest: The header was not found in the request, but it was required. HttpInvalidHeader: The header contained a malformed/invalid value. """ try: http_int = self.get_header(header, required=required) return int(http_int) except TypeError: # When the header does not exist and isn't required return None except ValueError: msg = 'The value of the header must be an integer.' raise errors.HTTPInvalidHeader(msg, header)
[文档] def get_header_as_datetime(self, header, required=False, obs_date=False): """Return an HTTP header with HTTP-Date values as a datetime. Args: name (str): Header name, case-insensitive (e.g., 'Date') Keyword Args: required (bool): Set to ``True`` to raise ``HTTPBadRequest`` instead of returning gracefully when the header is not found (default ``False``). obs_date (bool): Support obs-date formats according to RFC 7231, e.g.: "Sunday, 06-Nov-94 08:49:37 GMT" (default ``False``). Returns: datetime: The value of the specified header if it exists, or ``None`` if the header is not found and is not required. Raises: HTTPBadRequest: The header was not found in the request, but it was required. HttpInvalidHeader: The header contained a malformed/invalid value. """ try: http_date = self.get_header(header, required=required) return util.http_date_to_dt(http_date, obs_date=obs_date) except TypeError: # When the header does not exist and isn't required return None except ValueError: msg = 'It must be formatted according to RFC 7231, Section 7.1.1.1' raise errors.HTTPInvalidHeader(msg, header)
[文档] def get_param(self, name, required=False, store=None, default=None): """Return the raw value of a query string parameter as a string. Note: If an HTML form is POSTed to the API using the *application/x-www-form-urlencoded* media type, Falcon can automatically parse the parameters from the request body and merge them into the query string parameters. To enable this functionality, set :py:attr:`~.RequestOptions.auto_parse_form_urlencoded` to ``True`` via :any:`App.req_options`. Note, however, that the :attr:`~.RequestOptions.auto_parse_form_urlencoded` option is considered deprecated as of Falcon 3.0 in favor of accessing the URL-encoded form via :attr:`~Request.media`, and it may be removed in a future release. See also: :ref:`access_urlencoded_form` Note: Similar to the way multiple keys in form data are handled, if a query parameter is included in the query string multiple times, only one of those values will be returned, and it is undefined which one. This caveat also applies when :attr:`~falcon.RequestOptions.auto_parse_qs_csv` is enabled and the given parameter is assigned to a comma-separated list of values (e.g., ``foo=a,b,c``). When multiple values are expected for a parameter, :meth:`~.get_param_as_list` can be used to retrieve all of them at once. Args: name (str): Parameter name, case-sensitive (e.g., 'sort'). Keyword Args: required (bool): Set to ``True`` to raise ``HTTPBadRequest`` instead of returning ``None`` when the parameter is not found (default ``False``). store (dict): A ``dict``-like object in which to place the value of the param, but only if the param is present. default (any): If the param is not found returns the given value instead of ``None`` Returns: str: The value of the param as a string, or ``None`` if param is not found and is not required. Raises: HTTPBadRequest: A required param is missing from the request. """ params = self._params # PERF: Use if..in since it is a good all-around performer; we don't # know how likely params are to be specified by clients. if name in params: # NOTE(warsaw): If the key appeared multiple times, it will be # stored internally as a list. We do not define which one # actually gets returned, but let's pick the last one for grins. param = params[name] if isinstance(param, list): param = param[-1] if store is not None: store[name] = param return param if not required: return default raise errors.HTTPMissingParam(name)
[文档] def get_param_as_int( self, name, required=False, min_value=None, max_value=None, store=None, default=None, ): """Return the value of a query string parameter as an int. Args: name (str): Parameter name, case-sensitive (e.g., 'limit'). Keyword Args: required (bool): Set to ``True`` to raise ``HTTPBadRequest`` instead of returning ``None`` when the parameter is not found or is not an integer (default ``False``). min_value (int): Set to the minimum value allowed for this param. If the param is found and it is less than min_value, an ``HTTPError`` is raised. max_value (int): Set to the maximum value allowed for this param. If the param is found and its value is greater than max_value, an ``HTTPError`` is raised. store (dict): A ``dict``-like object in which to place the value of the param, but only if the param is found (default ``None``). default (any): If the param is not found returns the given value instead of ``None`` Returns: int: The value of the param if it is found and can be converted to an ``int``. If the param is not found, returns ``None``, unless `required` is ``True``. Raises HTTPBadRequest: The param was not found in the request, even though it was required to be there, or it was found but could not be converted to an ``int``. Also raised if the param's value falls outside the given interval, i.e., the value must be in the interval: min_value <= value <= max_value to avoid triggering an error. """ params = self._params # PERF: Use if..in since it is a good all-around performer; we don't # know how likely params are to be specified by clients. if name in params: val = params[name] if isinstance(val, list): val = val[-1] try: val = int(val) except ValueError: msg = 'The value must be an integer.' raise errors.HTTPInvalidParam(msg, name) if min_value is not None and val < min_value: msg = 'The value must be at least ' + str(min_value) raise errors.HTTPInvalidParam(msg, name) if max_value is not None and max_value < val: msg = 'The value may not exceed ' + str(max_value) raise errors.HTTPInvalidParam(msg, name) if store is not None: store[name] = val return val if not required: return default raise errors.HTTPMissingParam(name)
[文档] def get_param_as_float( self, name, required=False, min_value=None, max_value=None, store=None, default=None, ): """Return the value of a query string parameter as an float. Args: name (str): Parameter name, case-sensitive (e.g., 'limit'). Keyword Args: required (bool): Set to ``True`` to raise ``HTTPBadRequest`` instead of returning ``None`` when the parameter is not found or is not an float (default ``False``). min_value (float): Set to the minimum value allowed for this param. If the param is found and it is less than min_value, an ``HTTPError`` is raised. max_value (float): Set to the maximum value allowed for this param. If the param is found and its value is greater than max_value, an ``HTTPError`` is raised. store (dict): A ``dict``-like object in which to place the value of the param, but only if the param is found (default ``None``). default (any): If the param is not found returns the given value instead of ``None`` Returns: float: The value of the param if it is found and can be converted to an ``float``. If the param is not found, returns ``None``, unless `required` is ``True``. Raises HTTPBadRequest: The param was not found in the request, even though it was required to be there, or it was found but could not be converted to an ``float``. Also raised if the param's value falls outside the given interval, i.e., the value must be in the interval: min_value <= value <= max_value to avoid triggering an error. """ params = self._params # PERF: Use if..in since it is a good all-around performer; we don't # know how likely params are to be specified by clients. if name in params: val = params[name] if isinstance(val, list): val = val[-1] try: val = float(val) except ValueError: msg = 'The value must be a float.' raise errors.HTTPInvalidParam(msg, name) if min_value is not None and val < min_value: msg = 'The value must be at least ' + str(min_value) raise errors.HTTPInvalidParam(msg, name) if max_value is not None and max_value < val: msg = 'The value may not exceed ' + str(max_value) raise errors.HTTPInvalidParam(msg, name) if store is not None: store[name] = val return val if not required: return default raise errors.HTTPMissingParam(name)
[文档] def get_param_as_uuid(self, name, required=False, store=None, default=None): """Return the value of a query string parameter as an UUID. The value to convert must conform to the standard UUID string representation per RFC 4122. For example, the following strings are all valid:: # Lowercase '64be949b-3433-4d36-a4a8-9f19d352fee8' # Uppercase 'BE71ECAA-F719-4D42-87FD-32613C2EEB60' # Mixed '81c8155C-D6de-443B-9495-39Fa8FB239b5' Args: name (str): Parameter name, case-sensitive (e.g., 'id'). Keyword Args: required (bool): Set to ``True`` to raise ``HTTPBadRequest`` instead of returning ``None`` when the parameter is not found or is not a UUID (default ``False``). store (dict): A ``dict``-like object in which to place the value of the param, but only if the param is found (default ``None``). default (any): If the param is not found returns the given value instead of ``None`` Returns: UUID: The value of the param if it is found and can be converted to a ``UUID``. If the param is not found, returns ``default`` (default ``None``), unless `required` is ``True``. Raises HTTPBadRequest: The param was not found in the request, even though it was required to be there, or it was found but could not be converted to a ``UUID``. """ params = self._params # PERF: Use if..in since it is a good all-around performer; we don't # know how likely params are to be specified by clients. if name in params: val = params[name] if isinstance(val, list): val = val[-1] try: val = UUID(val) except ValueError: msg = 'The value must be a UUID string.' raise errors.HTTPInvalidParam(msg, name) if store is not None: store[name] = val return val if not required: return default raise errors.HTTPMissingParam(name)
[文档] def get_param_as_bool( self, name, required=False, store=None, blank_as_true=True, default=None ): """Return the value of a query string parameter as a boolean. This method treats valueless parameters as flags. By default, if no value is provided for the parameter in the query string, ``True`` is assumed and returned. If the parameter is missing altogether, ``None`` is returned as with other ``get_param_*()`` methods, which can be easily treated as falsy by the caller as needed. The following boolean strings are supported:: TRUE_STRINGS = ('true', 'True', 't', 'yes', 'y', '1', 'on') FALSE_STRINGS = ('false', 'False', 'f', 'no', 'n', '0', 'off') Args: name (str): Parameter name, case-sensitive (e.g., 'detailed'). Keyword Args: required (bool): Set to ``True`` to raise ``HTTPBadRequest`` instead of returning ``None`` when the parameter is not found or is not a recognized boolean string (default ``False``). store (dict): A ``dict``-like object in which to place the value of the param, but only if the param is found (default ``None``). blank_as_true (bool): Valueless query string parameters are treated as flags, resulting in ``True`` being returned when such a parameter is present, and ``False`` otherwise. To require the client to explicitly opt-in to a truthy value, pass ``blank_as_true=False`` to return ``False`` when a value is not specified in the query string. default (any): If the param is not found, return this value instead of ``None``. Returns: bool: The value of the param if it is found and can be converted to a ``bool``. If the param is not found, returns ``None`` unless `required` is ``True``. Raises: HTTPBadRequest: A required param is missing from the request, or can not be converted to a ``bool``. """ params = self._params # PERF: Use if..in since it is a good all-around performer; we don't # know how likely params are to be specified by clients. if name in params: val = params[name] if isinstance(val, list): val = val[-1] if val in TRUE_STRINGS: val = True elif val in FALSE_STRINGS: val = False elif not val: val = blank_as_true else: msg = 'The value of the parameter must be "true" or "false".' raise errors.HTTPInvalidParam(msg, name) if store is not None: store[name] = val return val if not required: return default raise errors.HTTPMissingParam(name)
[文档] def get_param_as_list( self, name, transform=None, required=False, store=None, default=None ): """Return the value of a query string parameter as a list. List items must be comma-separated or must be provided as multiple instances of the same param in the query string ala *application/x-www-form-urlencoded*. Note: To enable the interpretation of comma-separated parameter values, the :attr:`~falcon.RequestOptions.auto_parse_qs_csv` option must be set to ``True`` (default ``False``). Args: name (str): Parameter name, case-sensitive (e.g., 'ids'). Keyword Args: transform (callable): An optional transform function that takes as input each element in the list as a ``str`` and outputs a transformed element for inclusion in the list that will be returned. For example, passing ``int`` will transform list items into numbers. required (bool): Set to ``True`` to raise ``HTTPBadRequest`` instead of returning ``None`` when the parameter is not found (default ``False``). store (dict): A ``dict``-like object in which to place the value of the param, but only if the param is found (default ``None``). default (any): If the param is not found returns the given value instead of ``None`` Returns: list: The value of the param if it is found. Otherwise, returns ``None`` unless *required* is ``True``. Empty list elements will be included by default, but this behavior can be configured by setting the :attr:`~falcon.RequestOptions.keep_blank_qs_values` option. For example, by default the following query strings would both result in ``['1', '', '3']``:: things=1&things=&things=3 things=1,,3 Note, however, that for the second example string above to be interpreted as a list, the :attr:`~falcon.RequestOptions.auto_parse_qs_csv` option must be set to ``True``. Raises: HTTPBadRequest: A required param is missing from the request, or a transform function raised an instance of ``ValueError``. """ params = self._params # PERF: Use if..in since it is a good all-around performer; we don't # know how likely params are to be specified by clients. if name in params: items = params[name] # NOTE(warsaw): When a key appears multiple times in the request # query, it will already be represented internally as a list. # NOTE(kgriffs): Likewise for comma-delimited values. if not isinstance(items, list): items = [items] # PERF(kgriffs): Use if-else rather than a DRY approach # that sets transform to a passthrough function; avoids # function calling overhead. if transform is not None: try: items = [transform(i) for i in items] except ValueError: msg = 'The value is not formatted correctly.' raise errors.HTTPInvalidParam(msg, name) if store is not None: store[name] = items return items if not required: return default raise errors.HTTPMissingParam(name)
[文档] def get_param_as_datetime( self, name, format_string='%Y-%m-%dT%H:%M:%SZ', required=False, store=None, default=None, ): """Return the value of a query string parameter as a datetime. Args: name (str): Parameter name, case-sensitive (e.g., 'ids'). Keyword Args: format_string (str): String used to parse the param value into a ``datetime``. Any format recognized by strptime() is supported (default ``'%Y-%m-%dT%H:%M:%SZ'``). required (bool): Set to ``True`` to raise ``HTTPBadRequest`` instead of returning ``None`` when the parameter is not found (default ``False``). store (dict): A ``dict``-like object in which to place the value of the param, but only if the param is found (default ``None``). default (any): If the param is not found returns the given value instead of ``None`` Returns: datetime.datetime: The value of the param if it is found and can be converted to a ``datetime`` according to the supplied format string. If the param is not found, returns ``None`` unless required is ``True``. Raises: HTTPBadRequest: A required param is missing from the request, or the value could not be converted to a ``datetime``. """ param_value = self.get_param(name, required=required) if param_value is None: return default try: date_time = strptime(param_value, format_string) except ValueError: msg = 'The date value does not match the required format.' raise errors.HTTPInvalidParam(msg, name) if store is not None: store[name] = date_time return date_time
[文档] def get_param_as_date( self, name, format_string='%Y-%m-%d', required=False, store=None, default=None ): """Return the value of a query string parameter as a date. Args: name (str): Parameter name, case-sensitive (e.g., 'ids'). Keyword Args: format_string (str): String used to parse the param value into a date. Any format recognized by strptime() is supported (default ``"%Y-%m-%d"``). required (bool): Set to ``True`` to raise ``HTTPBadRequest`` instead of returning ``None`` when the parameter is not found (default ``False``). store (dict): A ``dict``-like object in which to place the value of the param, but only if the param is found (default ``None``). default (any): If the param is not found returns the given value instead of ``None`` Returns: datetime.date: The value of the param if it is found and can be converted to a ``date`` according to the supplied format string. If the param is not found, returns ``None`` unless required is ``True``. Raises: HTTPBadRequest: A required param is missing from the request, or the value could not be converted to a ``date``. """ date_time = self.get_param_as_datetime(name, format_string, required) if date_time: date = date_time.date() else: return default if store is not None: store[name] = date return date
[文档] def get_param_as_json(self, name, required=False, store=None, default=None): """Return the decoded JSON value of a query string parameter. Given a JSON value, decode it to an appropriate Python type, (e.g., ``dict``, ``list``, ``str``, ``int``, ``bool``, etc.) Warning: If the :attr:`~falcon.RequestOptions.auto_parse_qs_csv` option is set to ``True`` (default ``False``), the framework will misinterpret any JSON values that include literal (non-percent-encoded) commas. If the query string may include JSON, you can use JSON array syntax in lieu of CSV as a workaround. Args: name (str): Parameter name, case-sensitive (e.g., 'payload'). Keyword Args: required (bool): Set to ``True`` to raise ``HTTPBadRequest`` instead of returning ``None`` when the parameter is not found (default ``False``). store (dict): A ``dict``-like object in which to place the value of the param, but only if the param is found (default ``None``). default (any): If the param is not found returns the given value instead of ``None`` Returns: dict: The value of the param if it is found. Otherwise, returns ``None`` unless required is ``True``. Raises: HTTPBadRequest: A required param is missing from the request, or the value could not be parsed as JSON. """ param_value = self.get_param(name, required=required) if param_value is None: return default handler, _, _ = self.options.media_handlers._resolve( MEDIA_JSON, MEDIA_JSON, raise_not_found=False ) if handler is None: handler = _DEFAULT_JSON_HANDLER try: # TODO(CaselIT): find a way to avoid encode + BytesIO if handlers # interface is refactored. Possibly using the WS interface? val = handler.deserialize( BytesIO(param_value.encode()), MEDIA_JSON, len(param_value) ) except errors.HTTPBadRequest: msg = 'It could not be parsed as JSON.' raise errors.HTTPInvalidParam(msg, name) if store is not None: store[name] = val return val
[文档] def has_param(self, name): """Determine whether or not the query string parameter already exists. Args: name (str): Parameter name, case-sensitive (e.g., 'sort'). Returns: bool: ``True`` if param is found, or ``False`` if param is not found. """ if name in self._params: return True else: return False
[文档] def log_error(self, message): """Write an error message to the server's log. Prepends timestamp and request info to message, and writes the result out to the WSGI server's error stream (`wsgi.error`). Args: message (str): Description of the problem. """ if self.query_string: query_string_formatted = '?' + self.query_string else: query_string_formatted = '' log_line = DEFAULT_ERROR_LOG_FORMAT.format( now(), self.method, self.path, query_string_formatted ) self._wsgierrors.write(log_line + message + '\n')
# ------------------------------------------------------------------------ # Helpers # ------------------------------------------------------------------------ def _get_wrapped_wsgi_input(self): try: content_length = self.content_length or 0 # NOTE(kgriffs): This branch is indeed covered in test_wsgi.py # even though coverage isn't able to detect it. except errors.HTTPInvalidHeader: # pragma: no cover # NOTE(kgriffs): The content-length header was specified, # but it had an invalid value. Assume no content. content_length = 0 return BoundedStream(self.env['wsgi.input'], content_length) def _parse_form_urlencoded(self): content_length = self.content_length if not content_length: return body = self.stream.read(content_length) # NOTE(kgriffs): According to http://goo.gl/6rlcux the # body should be US-ASCII. Enforcing this also helps # catch malicious input. try: body = body.decode('ascii') except UnicodeDecodeError: body = None self.log_error( 'Non-ASCII characters found in form body ' 'with Content-Type of ' 'application/x-www-form-urlencoded. Body ' 'will be ignored.' ) if body: extra_params = parse_query_string( body, keep_blank=self.options.keep_blank_qs_values, csv=self.options.auto_parse_qs_csv, ) self._params.update(extra_params)
# PERF: To avoid typos and improve storage space and speed over a dict.
[文档]class RequestOptions: """Defines a set of configurable request options. An instance of this class is exposed via :attr:`falcon.App.req_options` and :attr:`falcon.asgi.App.req_options` for configuring certain :class:`~.Request` and :class:`falcon.asgi.Request` behaviors, respectively. Attributes: keep_blank_qs_values (bool): Set to ``False`` to ignore query string params that have missing or blank values (default ``True``). For comma-separated values, this option also determines whether or not empty elements in the parsed list are retained. auto_parse_form_urlencoded: Set to ``True`` in order to automatically consume the request stream and merge the results into the request's query string params when the request's content type is *application/x-www-form-urlencoded* (default ``False``). Enabling this option for WSGI apps makes the form parameters accessible via :attr:`~falcon.Request.params`, :meth:`~falcon.Request.get_param`, etc. Warning: The `auto_parse_form_urlencoded` option is not supported for ASGI apps, and is considered deprecated for WSGI apps as of Falcon 3.0, in favor of accessing URL-encoded forms through :attr:`~Request.media`. See also: :ref:`access_urlencoded_form` Warning: When this option is enabled, the request's body stream will be left at EOF. The original data is not retained by the framework. Note: The character encoding for fields, before percent-encoding non-ASCII bytes, is assumed to be UTF-8. The special `_charset_` field is ignored if present. Falcon expects form-encoded request bodies to be encoded according to the standard W3C algorithm (see also http://goo.gl/6rlcux). auto_parse_qs_csv: Set to ``True`` to split query string values on any non-percent-encoded commas (default ``False``). When ``False``, values containing commas are left as-is. In this mode, list items are taken only from multiples of the same parameter name within the query string (i.e. ``t=1,2,3&t=4`` becomes ``['1,2,3', '4']``). When `auto_parse_qs_csv` is set to ``True``, the query string value is also split on non-percent-encoded commas and these items are added to the final list (i.e. ``t=1,2,3&t=4,5`` becomes ``['1', '2', '3', '4', '5']``). Warning: Enabling this option will cause the framework to misinterpret any JSON values that include literal (non-percent-encoded) commas. If the query string may include JSON, you can use JSON array syntax in lieu of CSV as a workaround. strip_url_path_trailing_slash: Set to ``True`` in order to strip the trailing slash, if present, at the end of the URL path (default ``False``). When this option is enabled, the URL path is normalized by stripping the trailing slash character. This lets the application define a single route to a resource for a path that may or may not end in a forward slash. However, this behavior can be problematic in certain cases, such as when working with authentication schemes that employ URL-based signatures. default_media_type (str): The default media-type used to deserialize a request body, when the Content-Type header is missing or ambiguous. This value is normally set to the media type provided to the :class:`falcon.App` or :class:`falcon.asgi.App` initializer; however, if created independently, this will default to :attr:`falcon.DEFAULT_MEDIA_TYPE`. media_handlers (Handlers): A dict-like object for configuring the media-types to handle. By default, handlers are provided for the ``application/json``, ``application/x-www-form-urlencoded`` and ``multipart/form-data`` media types. """ keep_black_qs_values: bool auto_parse_form_urlencoded: bool auto_parse_qs_csv: bool strip_url_path_trailing_slash: bool default_media_type: str media_handlers: Handlers __slots__ = ( 'keep_blank_qs_values', 'auto_parse_form_urlencoded', 'auto_parse_qs_csv', 'strip_url_path_trailing_slash', 'default_media_type', 'media_handlers', ) def __init__(self): self.keep_blank_qs_values = True self.auto_parse_form_urlencoded = False self.auto_parse_qs_csv = False self.strip_url_path_trailing_slash = False self.default_media_type = DEFAULT_MEDIA_TYPE self.media_handlers = Handlers()