# -*- coding: utf-8 -*-
# Copyright (c) 2014 Rackspace
# Copyright (c) 2015 Ian Cordasco
# 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.
from collections import namedtuple
from .compat import to_str
from .exceptions import InvalidAuthority, ResolutionError
from .misc import (
ABSOLUTE_URI_MATCHER, FRAGMENT_MATCHER, IPv4_MATCHER, PATH_MATCHER,
QUERY_MATCHER, SCHEME_MATCHER, SUBAUTHORITY_MATCHER, URI_MATCHER,
URI_COMPONENTS, merge_paths
)
from .normalizers import (
encode_component, normalize_scheme, normalize_authority, normalize_path,
normalize_query, normalize_fragment
)
class URIReference(namedtuple('URIReference', URI_COMPONENTS)):
slots = ()
def __new__(cls, scheme, authority, path, query, fragment,
encoding='utf-8'):
ref = super(URIReference, cls).__new__(
cls,
scheme or None,
authority or None,
path or None,
query or None,
fragment or None)
ref.encoding = encoding
return ref
def __eq__(self, other):
other_ref = other
if isinstance(other, tuple):
other_ref = URIReference(*other)
elif not isinstance(other, URIReference):
try:
other_ref = URIReference.from_string(other)
except TypeError:
raise TypeError(
'Unable to compare URIReference() to {0}()'.format(
type(other).__name__))
# See http://tools.ietf.org/html/rfc3986#section-6.2
naive_equality = tuple(self) == tuple(other_ref)
return naive_equality or self.normalized_equality(other_ref)
@classmethod
def from_string(cls, uri_string, encoding='utf-8'):
"""Parse a URI reference from the given unicode URI string.
:param str uri_string: Unicode URI to be parsed into a reference.
:param str encoding: The encoding of the string provided
:returns: :class:`URIReference` or subclass thereof
"""
uri_string = to_str(uri_string, encoding)
split_uri = URI_MATCHER.match(uri_string).groupdict()
return cls(split_uri['scheme'], split_uri['authority'],
encode_component(split_uri['path'], encoding),
encode_component(split_uri['query'], encoding),
encode_component(split_uri['fragment'], encoding), encoding)
def authority_info(self):
"""Returns a dictionary with the ``userinfo``, ``host``, and ``port``.
If the authority is not valid, it will raise a ``InvalidAuthority``
Exception.
:returns:
``{'userinfo': 'username:password', 'host': 'www.example.com',
'port': '80'}``
:rtype: dict
:raises InvalidAuthority: If the authority is not ``None`` and can not
be parsed.
"""
if not self.authority:
return {'userinfo': None, 'host': None, 'port': None}
match = SUBAUTHORITY_MATCHER.match(self.authority)
if match is None:
# In this case, we have an authority that was parsed from the URI
# Reference, but it cannot be further parsed by our
# SUBAUTHORITY_MATCHER. In this case it must not be a valid
# authority.
raise InvalidAuthority(self.authority.encode(self.encoding))
# We had a match, now let's ensure that it is actually a valid host
# address if it is IPv4
matches = match.groupdict()
host = matches.get('host')
if (host and IPv4_MATCHER.match(host) and not
valid_ipv4_host_address(host)):
# If we have a host, it appears to be IPv4 and it does not have
# valid bytes, it is an InvalidAuthority.
raise InvalidAuthority(self.authority.encode(self.encoding))
return matches
@property
def host(self):
"""If present, a string representing the host."""
try:
authority = self.authority_info()
except InvalidAuthority:
return None
return authority['host']
@property
def port(self):
"""If present, the port (as a string) extracted from the authority."""
try:
authority = self.authority_info()
except InvalidAuthority:
return None
return authority['port']
@property
def userinfo(self):
"""If present, the userinfo extracted from the authority."""
try:
authority = self.authority_info()
except InvalidAuthority:
return None
return authority['userinfo']
def is_absolute(self):
"""Determine if this URI Reference is an absolute URI.
See http://tools.ietf.org/html/rfc3986#section-4.3 for explanation.
:returns: ``True`` if it is an absolute URI, ``False`` otherwise.
:rtype: bool
"""
return bool(ABSOLUTE_URI_MATCHER.match(self.unsplit()))
def is_valid(self, **kwargs):
"""Determines if the URI is valid.
:param bool require_scheme: Set to ``True`` if you wish to require the
presence of the scheme component.
:param bool require_authority: Set to ``True`` if you wish to require
the presence of the authority component.
:param bool require_path: Set to ``True`` if you wish to require the
presence of the path component.
:param bool require_query: Set to ``True`` if you wish to require the
presence of the query component.
:param bool require_fragment: Set to ``True`` if you wish to require
the presence of the fragment component.
:returns: ``True`` if the URI is valid. ``False`` otherwise.
:rtype: bool
"""
validators = [
(self.scheme_is_valid, kwargs.get('require_scheme', False)),
(self.authority_is_valid, kwargs.get('require_authority', False)),
(self.path_is_valid, kwargs.get('require_path', False)),
(self.query_is_valid, kwargs.get('require_query', False)),
(self.fragment_is_valid, kwargs.get('require_fragment', False)),
]
return all(v(r) for v, r in validators)
def _is_valid(self, value, matcher, require):
if require:
return (value is not None
and matcher.match(value))
# require is False and value is not None
return value is None or matcher.match(value)
def authority_is_valid(self, require=False):
"""Determines if the authority component is valid.
:param str require: Set to ``True`` to require the presence of this
component.
:returns: ``True`` if the authority is valid. ``False`` otherwise.
:rtype: bool
"""
try:
self.authority_info()
except InvalidAuthority:
return False
is_valid = self._is_valid(self.authority,
SUBAUTHORITY_MATCHER,
require)
# Ensure that IPv4 addresses have valid bytes
if is_valid and self.host and IPv4_MATCHER.match(self.host):
return valid_ipv4_host_address(self.host)
# Perhaps the host didn't exist or if it did, it wasn't an IPv4-like
# address. In either case, we want to rely on the `_is_valid` check,
# so let's return that.
return is_valid
def scheme_is_valid(self, require=False):
"""Determines if the scheme component is valid.
:param str require: Set to ``True`` to require the presence of this
component.
:returns: ``True`` if the scheme is valid. ``False`` otherwise.
:rtype: bool
"""
return self._is_valid(self.scheme, SCHEME_MATCHER, require)
def path_is_valid(self, require=False):
"""Determines if the path component is valid.
:param str require: Set to ``True`` to require the presence of this
component.
:returns: ``True`` if the path is valid. ``False`` otherwise.
:rtype: bool
"""
return self._is_valid(self.path, PATH_MATCHER, require)
def query_is_valid(self, require=False):
"""Determines if the query component is valid.
:param str require: Set to ``True`` to require the presence of this
component.
:returns: ``True`` if the query is valid. ``False`` otherwise.
:rtype: bool
"""
return self._is_valid(self.query, QUERY_MATCHER, require)
def fragment_is_valid(self, require=False):
"""Determines if the fragment component is valid.
:param str require: Set to ``True`` to require the presence of this
component.
:returns: ``True`` if the fragment is valid. ``False`` otherwise.
:rtype: bool
"""
return self._is_valid(self.fragment, FRAGMENT_MATCHER, require)
def normalize(self):
"""Normalize this reference as described in Section 6.2.2
This is not an in-place normalization. Instead this creates a new
URIReference.
:returns: A new reference object with normalized components.
:rtype: URIReference
"""
# See http://tools.ietf.org/html/rfc3986#section-6.2.2 for logic in
# this method.
return URIReference(normalize_scheme(self.scheme or ''),
normalize_authority(
(self.userinfo, self.host, self.port)),
normalize_path(self.path or ''),
normalize_query(self.query or ''),
normalize_fragment(self.fragment or ''))
def normalized_equality(self, other_ref):
"""Compare this URIReference to another URIReference.
:param URIReference other_ref: (required), The reference with which
we're comparing.
:returns: ``True`` if the references are equal, ``False`` otherwise.
:rtype: bool
"""
return tuple(self.normalize()) == tuple(other_ref.normalize())
def resolve_with(self, base_uri, strict=False):
"""Use an absolute URI Reference to resolve this relative reference.
Assuming this is a relative reference that you would like to resolve,
use the provided base URI to resolve it.
See http://tools.ietf.org/html/rfc3986#section-5 for more information.
:param base_uri: Either a string or URIReference. It must be an
absolute URI or it will raise an exception.
:returns: A new URIReference which is the result of resolving this
reference using ``base_uri``.
:rtype: :class:`URIReference`
:raises ResolutionError: If the ``base_uri`` is not an absolute URI.
"""
if not isinstance(base_uri, URIReference):
base_uri = URIReference.from_string(base_uri)
if not base_uri.is_absolute():
raise ResolutionError(base_uri)
# This is optional per
# http://tools.ietf.org/html/rfc3986#section-5.2.1
base_uri = base_uri.normalize()
# The reference we're resolving
resolving = self
if not strict and resolving.scheme == base_uri.scheme:
resolving = resolving.copy_with(scheme=None)
# http://tools.ietf.org/html/rfc3986#page-32
if resolving.scheme is not None:
target = resolving.copy_with(path=normalize_path(resolving.path))
else:
if resolving.authority is not None:
target = resolving.copy_with(
scheme=base_uri.scheme,
path=normalize_path(resolving.path)
)
else:
if resolving.path is None:
if resolving.query is not None:
query = resolving.query
else:
query = base_uri.query
target = resolving.copy_with(
scheme=base_uri.scheme,
authority=base_uri.authority,
path=base_uri.path,
query=query
)
else:
if resolving.path.startswith('/'):
path = normalize_path(resolving.path)
else:
path = normalize_path(
merge_paths(base_uri, resolving.path)
)
target = resolving.copy_with(
scheme=base_uri.scheme,
authority=base_uri.authority,
path=path,
query=resolving.query
)
return target
def unsplit(self):
"""Create a URI string from the components.
:returns: The URI Reference reconstituted as a string.
:rtype: str
"""
# See http://tools.ietf.org/html/rfc3986#section-5.3
result_list = []
if self.scheme:
result_list.extend([self.scheme, ':'])
if self.authority:
result_list.extend(['//', self.authority])
if self.path:
result_list.append(self.path)
if self.query:
result_list.extend(['?', self.query])
if self.fragment:
result_list.extend(['#', self.fragment])
return ''.join(result_list)
def copy_with(self, scheme=None, authority=None, path=None, query=None,
fragment=None):
attributes = {
'scheme': scheme,
'authority': authority,
'path': path,
'query': query,
'fragment': fragment,
}
for key, value in list(attributes.items()):
if value is None:
del attributes[key]
return self._replace(**attributes)
def valid_ipv4_host_address(host):
# If the host exists, and it might be IPv4, check each byte in the
# address.
return all([0 <= int(byte, base=10) <= 255 for byte in host.split('.')])