"""
Fixers
======
.. warning::
.. deprecated:: 0.15
``ProxyFix`` has moved to :mod:`werkzeug.middleware.proxy_fix`.
All other code in this module is deprecated and will be removed
in version 1.0.
.. versionadded:: 0.5
This module includes various helpers that fix web server behavior.
.. autoclass:: ProxyFix
:members:
.. autoclass:: CGIRootFix
.. autoclass:: PathInfoFromRequestUriFix
.. autoclass:: HeaderRewriterFix
.. autoclass:: InternetExplorerFix
:copyright: 2007 Pallets
:license: BSD-3-Clause
"""
import warnings
from ..datastructures import Headers
from ..datastructures import ResponseCacheControl
from ..http import parse_cache_control_header
from ..http import parse_options_header
from ..http import parse_set_header
from ..middleware.proxy_fix import ProxyFix as _ProxyFix
from ..useragents import UserAgent
try:
from urllib.parse import unquote
except ImportError:
from urllib import unquote
class CGIRootFix(object):
"""Wrap the application in this middleware if you are using FastCGI
or CGI and you have problems with your app root being set to the CGI
script's path instead of the path users are going to visit.
:param app: the WSGI application
:param app_root: Defaulting to ``'/'``, you can set this to
something else if your app is mounted somewhere else.
.. deprecated:: 0.15
This middleware will be removed in version 1.0.
.. versionchanged:: 0.9
Added `app_root` parameter and renamed from
``LighttpdCGIRootFix``.
"""
def __init__(self, app, app_root="/"):
warnings.warn(
"'CGIRootFix' is deprecated as of version 0.15 and will be"
" removed in version 1.0.",
DeprecationWarning,
stacklevel=2,
)
self.app = app
self.app_root = app_root.strip("/")
def __call__(self, environ, start_response):
environ["SCRIPT_NAME"] = self.app_root
return self.app(environ, start_response)
class LighttpdCGIRootFix(CGIRootFix):
def __init__(self, *args, **kwargs):
warnings.warn(
"'LighttpdCGIRootFix' is renamed 'CGIRootFix'. Both will be"
" removed in version 1.0.",
DeprecationWarning,
stacklevel=2,
)
super(LighttpdCGIRootFix, self).__init__(*args, **kwargs)
class PathInfoFromRequestUriFix(object):
"""On windows environment variables are limited to the system charset
which makes it impossible to store the `PATH_INFO` variable in the
environment without loss of information on some systems.
This is for example a problem for CGI scripts on a Windows Apache.
This fixer works by recreating the `PATH_INFO` from `REQUEST_URI`,
`REQUEST_URL`, or `UNENCODED_URL` (whatever is available). Thus the
fix can only be applied if the webserver supports either of these
variables.
:param app: the WSGI application
.. deprecated:: 0.15
This middleware will be removed in version 1.0.
"""
def __init__(self, app):
warnings.warn(
"'PathInfoFromRequestUriFix' is deprecated as of version"
" 0.15 and will be removed in version 1.0.",
DeprecationWarning,
stacklevel=2,
)
self.app = app
def __call__(self, environ, start_response):
for key in "REQUEST_URL", "REQUEST_URI", "UNENCODED_URL":
if key not in environ:
continue
request_uri = unquote(environ[key])
script_name = unquote(environ.get("SCRIPT_NAME", ""))
if request_uri.startswith(script_name):
environ["PATH_INFO"] = request_uri[len(script_name) :].split("?", 1)[0]
break
return self.app(environ, start_response)
class ProxyFix(_ProxyFix):
"""
.. deprecated:: 0.15
``werkzeug.contrib.fixers.ProxyFix`` has moved to
:mod:`werkzeug.middleware.proxy_fix`. This import will be
removed in 1.0.
"""
def __init__(self, *args, **kwargs):
warnings.warn(
"'werkzeug.contrib.fixers.ProxyFix' has moved to 'werkzeug"
".middleware.proxy_fix.ProxyFix'. This import is deprecated"
" as of version 0.15 and will be removed in 1.0.",
DeprecationWarning,
stacklevel=2,
)
super(ProxyFix, self).__init__(*args, **kwargs)
class HeaderRewriterFix(object):
"""This middleware can remove response headers and add others. This
is for example useful to remove the `Date` header from responses if you
are using a server that adds that header, no matter if it's present or
not or to add `X-Powered-By` headers::
app = HeaderRewriterFix(app, remove_headers=['Date'],
add_headers=[('X-Powered-By', 'WSGI')])
:param app: the WSGI application
:param remove_headers: a sequence of header keys that should be
removed.
:param add_headers: a sequence of ``(key, value)`` tuples that should
be added.
.. deprecated:: 0.15
This middleware will be removed in 1.0.
"""
def __init__(self, app, remove_headers=None, add_headers=None):
warnings.warn(
"'HeaderRewriterFix' is deprecated as of version 0.15 and"
" will be removed in version 1.0.",
DeprecationWarning,
stacklevel=2,
)
self.app = app
self.remove_headers = set(x.lower() for x in (remove_headers or ()))
self.add_headers = list(add_headers or ())
def __call__(self, environ, start_response):
def rewriting_start_response(status, headers, exc_info=None):
new_headers = []
for key, value in headers:
if key.lower() not in self.remove_headers:
new_headers.append((key, value))
new_headers += self.add_headers
return start_response(status, new_headers, exc_info)
return self.app(environ, rewriting_start_response)
class InternetExplorerFix(object):
"""This middleware fixes a couple of bugs with Microsoft Internet
Explorer. Currently the following fixes are applied:
- removing of `Vary` headers for unsupported mimetypes which
causes troubles with caching. Can be disabled by passing
``fix_vary=False`` to the constructor.
see: https://support.microsoft.com/en-us/help/824847
- removes offending headers to work around caching bugs in
Internet Explorer if `Content-Disposition` is set. Can be
disabled by passing ``fix_attach=False`` to the constructor.
If it does not detect affected Internet Explorer versions it won't touch
the request / response.
.. deprecated:: 0.15
This middleware will be removed in 1.0.
"""
# This code was inspired by Django fixers for the same bugs. The
# fix_vary and fix_attach fixers were originally implemented in Django
# by Michael Axiak and is available as part of the Django project:
# https://code.djangoproject.com/ticket/4148
def __init__(self, app, fix_vary=True, fix_attach=True):
warnings.warn(
"'InternetExplorerFix' is deprecated as of version 0.15 and"
" will be removed in version 1.0.",
DeprecationWarning,
stacklevel=2,
)
self.app = app
self.fix_vary = fix_vary
self.fix_attach = fix_attach
def fix_headers(self, environ, headers, status=None):
if self.fix_vary:
header = headers.get("content-type", "")
mimetype, options = parse_options_header(header)
if mimetype not in ("text/html", "text/plain", "text/sgml"):
headers.pop("vary", None)
if self.fix_attach and "content-disposition" in headers:
pragma = parse_set_header(headers.get("pragma", ""))
pragma.discard("no-cache")
header = pragma.to_header()
if not header:
headers.pop("pragma", "")
else:
headers["Pragma"] = header
header = headers.get("cache-control", "")
if header:
cc = parse_cache_control_header(header, cls=ResponseCacheControl)
cc.no_cache = None
cc.no_store = False
header = cc.to_header()
if not header:
headers.pop("cache-control", "")
else:
headers["Cache-Control"] = header
def run_fixed(self, environ, start_response):
def fixing_start_response(status, headers, exc_info=None):
headers = Headers(headers)
self.fix_headers(environ, headers, status)
return start_response(status, headers.to_wsgi_list(), exc_info)
return self.app(environ, fixing_start_response)
def __call__(self, environ, start_response):
ua = UserAgent(environ)
if ua.browser != "msie":
return self.app(environ, start_response)
return self.run_fixed(environ, start_response)