from __future__ import absolute_import
from collections import namedtuple
import re
from ..exceptions import LocationParseError
from ..packages.six.moves.urllib.parse import quote
url_attrs = ['scheme', 'auth', 'host', 'port', 'path', 'query', 'fragment']
# We only want to normalize urls with an HTTP(S) scheme.
# urllib3 infers URLs without a scheme (None) to be http.
NORMALIZABLE_SCHEMES = ('http', 'https', None)
_contains_disallowed_url_pchar_re = re.compile('[\x00-\x20\x7f]')
class Url(namedtuple('Url', url_attrs)):
"""
Datastructure for representing an HTTP URL. Used as a return value for
:func:`parse_url`. Both the scheme and host are normalized as they are
both case-insensitive according to RFC 3986.
"""
__slots__ = ()
def __new__(cls, scheme=None, auth=None, host=None, port=None, path=None,
query=None, fragment=None):
if path and not path.startswith('/'):
path = '/' + path
if scheme:
scheme = scheme.lower()
if host and scheme in NORMALIZABLE_SCHEMES:
host = host.lower()
return super(Url, cls).__new__(cls, scheme, auth, host, port, path,
query, fragment)
@property
def hostname(self):
"""For backwards-compatibility with urlparse. We're nice like that."""
return self.host
@property
def request_uri(self):
"""Absolute path including the query string."""
uri = self.path or '/'
if self.query is not None:
uri += '?' + self.query
return uri
@property
def netloc(self):
"""Network location including host and port"""
if self.port:
return '%s:%d' % (self.host, self.port)
return self.host
@property
def url(self):
"""
Convert self into a url
This function should more or less round-trip with :func:`.parse_url`. The
returned url may not be exactly the same as the url inputted to
:func:`.parse_url`, but it should be equivalent by the RFC (e.g., urls
with a blank port will have : removed).
Example: ::
>>> U = parse_url('http://google.com/mail/')
>>> U.url
'http://google.com/mail/'
>>> Url('http', 'username:password', 'host.com', 80,
... '/path', 'query', 'fragment').url
'http://username:password@host.com:80/path?query#fragment'
"""
scheme, auth, host, port, path, query, fragment = self
url = ''
# We use "is not None" we want things to happen with empty strings (or 0 port)
if scheme is not None:
url += scheme + '://'
if auth is not None:
url += auth + '@'
if host is not None:
url += host
if port is not None:
url += ':' + str(port)
if path is not None:
url += path
if query is not None:
url += '?' + query
if fragment is not None:
url += '#' + fragment
return url
def __str__(self):
return self.url
def split_first(s, delims):
"""
Given a string and an iterable of delimiters, split on the first found
delimiter. Return two split parts and the matched delimiter.
If not found, then the first part is the full input string.
Example::
>>> split_first('foo/bar?baz', '?/=')
('foo', 'bar?baz', '/')
>>> split_first('foo/bar?baz', '123')
('foo/bar?baz', '', None)
Scales linearly with number of delims. Not ideal for large number of delims.
"""
min_idx = None
min_delim = None
for d in delims:
idx = s.find(d)
if idx < 0:
continue
if min_idx is None or idx < min_idx:
min_idx = idx
min_delim = d
if min_idx is None or min_idx < 0:
return s, '', None
return s[:min_idx], s[min_idx + 1:], min_delim
def parse_url(url):
"""
Given a url, return a parsed :class:`.Url` namedtuple. Best-effort is
performed to parse incomplete urls. Fields not provided will be None.
Partly backwards-compatible with :mod:`urlparse`.
Example::
>>> parse_url('http://google.com/mail/')
Url(scheme='http', host='google.com', port=None, path='/mail/', ...)
>>> parse_url('google.com:80')
Url(scheme=None, host='google.com', port=80, path=None, ...)
>>> parse_url('/foo?bar')
Url(scheme=None, host=None, port=None, path='/foo', query='bar', ...)
"""
# While this code has overlap with stdlib's urlparse, it is much
# simplified for our needs and less annoying.
# Additionally, this implementations does silly things to be optimal
# on CPython.
if not url:
# Empty
return Url()
# Prevent CVE-2019-9740.
# adapted from https://github.com/python/cpython/pull/12755
url = _contains_disallowed_url_pchar_re.sub(lambda match: quote(match.group()), url)
scheme = None
auth = None
host = None
port = None
path = None
fragment = None
query = None
# Scheme
if '://' in url:
scheme, url = url.split('://', 1)
# Find the earliest Authority Terminator
# (http://tools.ietf.org/html/rfc3986#section-3.2)
url, path_, delim = split_first(url, ['/', '?', '#'])
if delim:
# Reassemble the path
path = delim + path_
# Auth
if '@' in url:
# Last '@' denotes end of auth part
auth, url = url.rsplit('@', 1)
# IPv6
if url and url[0] == '[':
host, url = url.split(']', 1)
host += ']'
# Port
if ':' in url:
_host, port = url.split(':', 1)
if not host:
host = _host
if port:
# If given, ports must be integers. No whitespace, no plus or
# minus prefixes, no non-integer digits such as ^2 (superscript).
if not port.isdigit():
raise LocationParseError(url)
try:
port = int(port)
except ValueError:
raise LocationParseError(url)
else:
# Blank ports are cool, too. (rfc3986#section-3.2.3)
port = None
elif not host and url:
host = url
if not path:
return Url(scheme, auth, host, port, path, query, fragment)
# Fragment
if '#' in path:
path, fragment = path.split('#', 1)
# Query
if '?' in path:
path, query = path.split('?', 1)
return Url(scheme, auth, host, port, path, query, fragment)
def get_host(url):
"""
Deprecated. Use :func:`parse_url` instead.
"""
p = parse_url(url)
return p.scheme or 'http', p.hostname, p.port
