mirror of
https://github.com/janeczku/calibre-web
synced 2024-11-06 01:56:23 +00:00
245 lines
9.7 KiB
Python
245 lines
9.7 KiB
Python
# -*- coding: utf-8 -*-
|
|
"""
|
|
werkzeug.contrib.fixers
|
|
~~~~~~~~~~~~~~~~~~~~~~~
|
|
|
|
.. versionadded:: 0.5
|
|
|
|
This module includes various helpers that fix bugs in web servers. They may
|
|
be necessary for some versions of a buggy web server but not others. We try
|
|
to stay updated with the status of the bugs as good as possible but you have
|
|
to make sure whether they fix the problem you encounter.
|
|
|
|
If you notice bugs in webservers not fixed in this module consider
|
|
contributing a patch.
|
|
|
|
:copyright: Copyright 2009 by the Werkzeug Team, see AUTHORS for more details.
|
|
:license: BSD, see LICENSE for more details.
|
|
"""
|
|
try:
|
|
from urllib import unquote
|
|
except ImportError:
|
|
from urllib.parse import unquote
|
|
|
|
from werkzeug.http import parse_options_header, parse_cache_control_header, \
|
|
parse_set_header
|
|
from werkzeug.useragents import UserAgent
|
|
from werkzeug.datastructures import Headers, ResponseCacheControl
|
|
|
|
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
|
|
|
|
.. versionchanged:: 0.9
|
|
Added `app_root` parameter and renamed from `LighttpdCGIRootFix`.
|
|
|
|
:param app: the WSGI application
|
|
:param app_root: Defaulting to ``'/'``, you can set this to something else
|
|
if your app is mounted somewhere else.
|
|
"""
|
|
|
|
def __init__(self, app, app_root='/'):
|
|
self.app = app
|
|
self.app_root = app_root
|
|
|
|
def __call__(self, environ, start_response):
|
|
# only set PATH_INFO for older versions of Lighty or if no
|
|
# server software is provided. That's because the test was
|
|
# added in newer Werkzeug versions and we don't want to break
|
|
# people's code if they are using this fixer in a test that
|
|
# does not set the SERVER_SOFTWARE key.
|
|
if 'SERVER_SOFTWARE' not in environ or \
|
|
environ['SERVER_SOFTWARE'] < 'lighttpd/1.4.28':
|
|
environ['PATH_INFO'] = environ.get('SCRIPT_NAME', '') + \
|
|
environ.get('PATH_INFO', '')
|
|
environ['SCRIPT_NAME'] = self.app_root.strip('/')
|
|
return self.app(environ, start_response)
|
|
|
|
# backwards compatibility
|
|
LighttpdCGIRootFix = CGIRootFix
|
|
|
|
|
|
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
|
|
"""
|
|
|
|
def __init__(self, app):
|
|
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(object):
|
|
"""This middleware can be applied to add HTTP proxy support to an
|
|
application that was not designed with HTTP proxies in mind. It
|
|
sets `REMOTE_ADDR`, `HTTP_HOST` from `X-Forwarded` headers.
|
|
|
|
If you have more than one proxy server in front of your app, set
|
|
`num_proxies` accordingly.
|
|
|
|
Do not use this middleware in non-proxy setups for security reasons.
|
|
|
|
The original values of `REMOTE_ADDR` and `HTTP_HOST` are stored in
|
|
the WSGI environment as `werkzeug.proxy_fix.orig_remote_addr` and
|
|
`werkzeug.proxy_fix.orig_http_host`.
|
|
|
|
:param app: the WSGI application
|
|
:param num_proxies: the number of proxy servers in front of the app.
|
|
"""
|
|
|
|
def __init__(self, app, num_proxies=1):
|
|
self.app = app
|
|
self.num_proxies = num_proxies
|
|
|
|
def get_remote_addr(self, forwarded_for):
|
|
"""Selects the new remote addr from the given list of ips in
|
|
X-Forwarded-For. By default it picks the one that the `num_proxies`
|
|
proxy server provides. Before 0.9 it would always pick the first.
|
|
|
|
.. versionadded:: 0.8
|
|
"""
|
|
if len(forwarded_for) >= self.num_proxies:
|
|
return forwarded_for[-1 * self.num_proxies]
|
|
|
|
def __call__(self, environ, start_response):
|
|
getter = environ.get
|
|
forwarded_proto = getter('HTTP_X_FORWARDED_PROTO', '')
|
|
forwarded_for = getter('HTTP_X_FORWARDED_FOR', '').split(',')
|
|
forwarded_host = getter('HTTP_X_FORWARDED_HOST', '')
|
|
environ.update({
|
|
'werkzeug.proxy_fix.orig_wsgi_url_scheme': getter('wsgi.url_scheme'),
|
|
'werkzeug.proxy_fix.orig_remote_addr': getter('REMOTE_ADDR'),
|
|
'werkzeug.proxy_fix.orig_http_host': getter('HTTP_HOST')
|
|
})
|
|
forwarded_for = [x for x in [x.strip() for x in forwarded_for] if x]
|
|
remote_addr = self.get_remote_addr(forwarded_for)
|
|
if remote_addr is not None:
|
|
environ['REMOTE_ADDR'] = remote_addr
|
|
if forwarded_host:
|
|
environ['HTTP_HOST'] = forwarded_host
|
|
if forwarded_proto:
|
|
environ['wsgi.url_scheme'] = forwarded_proto
|
|
return self.app(environ, start_response)
|
|
|
|
|
|
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.
|
|
"""
|
|
|
|
def __init__(self, app, remove_headers=None, add_headers=None):
|
|
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: http://support.microsoft.com/kb/824847/en-us
|
|
|
|
- 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.
|
|
"""
|
|
|
|
# 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:
|
|
# http://code.djangoproject.com/ticket/4148
|
|
|
|
def __init__(self, app, fix_vary=True, fix_attach=True):
|
|
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)
|