Viewing file:  url.py (13.65 KB) -rw-r--r--
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from __future__ import absolute_import
import re
from collections import namedtuple
from ..exceptions import LocationParseError
from ..packages import six
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)
# Almost all of these patterns were derived from the
# 'rfc3986' module: https://github.com/python-hyper/rfc3986
PERCENT_RE = re.compile(r"%[a-fA-F0-9]{2}")
SCHEME_RE = re.compile(r"^(?:[a-zA-Z][a-zA-Z0-9+-]*:|/)")
URI_RE = re.compile(
r"^(?:([a-zA-Z][a-zA-Z0-9+.-]*):)?"
r"(?://([^\\/?#]*))?"
r"([^?#]*)"
r"(?:\?([^#]*))?"
r"(?:#(.*))?$",
re.UNICODE | re.DOTALL,
)
IPV4_PAT = r"(?:[0-9]{1,3}\.){3}[0-9]{1,3}"
HEX_PAT = "[0-9A-Fa-f]{1,4}"
LS32_PAT = "(?:{hex}:{hex}|{ipv4})".format(hex=HEX_PAT, ipv4=IPV4_PAT)
_subs = {"hex": HEX_PAT, "ls32": LS32_PAT}
_variations = [
# 6( h16 ":" ) ls32
"(?:%(hex)s:){6}%(ls32)s",
# "::" 5( h16 ":" ) ls32
"::(?:%(hex)s:){5}%(ls32)s",
# [ h16 ] "::" 4( h16 ":" ) ls32
"(?:%(hex)s)?::(?:%(hex)s:){4}%(ls32)s",
# [ *1( h16 ":" ) h16 ] "::" 3( h16 ":" ) ls32
"(?:(?:%(hex)s:)?%(hex)s)?::(?:%(hex)s:){3}%(ls32)s",
# [ *2( h16 ":" ) h16 ] "::" 2( h16 ":" ) ls32
"(?:(?:%(hex)s:){0,2}%(hex)s)?::(?:%(hex)s:){2}%(ls32)s",
# [ *3( h16 ":" ) h16 ] "::" h16 ":" ls32
"(?:(?:%(hex)s:){0,3}%(hex)s)?::%(hex)s:%(ls32)s",
# [ *4( h16 ":" ) h16 ] "::" ls32
"(?:(?:%(hex)s:){0,4}%(hex)s)?::%(ls32)s",
# [ *5( h16 ":" ) h16 ] "::" h16
"(?:(?:%(hex)s:){0,5}%(hex)s)?::%(hex)s",
# [ *6( h16 ":" ) h16 ] "::"
"(?:(?:%(hex)s:){0,6}%(hex)s)?::",
]
UNRESERVED_PAT = r"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789._!\-~"
IPV6_PAT = "(?:" + "|".join([x % _subs for x in _variations]) + ")"
ZONE_ID_PAT = "(?:%25|%)(?:[" + UNRESERVED_PAT + "]|%[a-fA-F0-9]{2})+"
IPV6_ADDRZ_PAT = r"\[" + IPV6_PAT + r"(?:" + ZONE_ID_PAT + r")?\]"
REG_NAME_PAT = r"(?:[^\[\]%:/?#]|%[a-fA-F0-9]{2})*"
TARGET_RE = re.compile(r"^(/[^?#]*)(?:\?([^#]*))?(?:#.*)?$")
IPV4_RE = re.compile("^" + IPV4_PAT + "$")
IPV6_RE = re.compile("^" + IPV6_PAT + "$")
IPV6_ADDRZ_RE = re.compile("^" + IPV6_ADDRZ_PAT + "$")
BRACELESS_IPV6_ADDRZ_RE = re.compile("^" + IPV6_ADDRZ_PAT[2:-2] + "$")
ZONE_ID_RE = re.compile("(" + ZONE_ID_PAT + r")\]$")
SUBAUTHORITY_PAT = (u"^(?:(.*)@)?(%s|%s|%s)(?::([0-9]{0,5}))?$") % (
REG_NAME_PAT,
IPV4_PAT,
IPV6_ADDRZ_PAT,
)
SUBAUTHORITY_RE = re.compile(SUBAUTHORITY_PAT, re.UNICODE | re.DOTALL)
UNRESERVED_CHARS = set(
"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789._-~"
)
SUB_DELIM_CHARS = set("!$&'()*+,;=")
USERINFO_CHARS = UNRESERVED_CHARS | SUB_DELIM_CHARS | {":"}
PATH_CHARS = USERINFO_CHARS | {"@", "/"}
QUERY_CHARS = FRAGMENT_CHARS = PATH_CHARS | {"?"}
class Url(namedtuple("Url", url_attrs)):
"""
Data structure 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 is not None:
scheme = scheme.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 = u""
# We use "is not None" we want things to happen with empty strings (or 0 port)
if scheme is not None:
url += scheme + u"://"
if auth is not None:
url += auth + u"@"
if host is not None:
url += host
if port is not None:
url += u":" + str(port)
if path is not None:
url += path
if query is not None:
url += u"?" + query
if fragment is not None:
url += u"#" + fragment
return url
def __str__(self):
return self.url
def split_first(s, delims):
"""
.. deprecated:: 1.25
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 _encode_invalid_chars(component, allowed_chars, encoding="utf-8"):
"""Percent-encodes a URI component without reapplying
onto an already percent-encoded component.
"""
if component is None:
return component
component = six.ensure_text(component)
# Normalize existing percent-encoded bytes.
# Try to see if the component we're encoding is already percent-encoded
# so we can skip all '%' characters but still encode all others.
component, percent_encodings = PERCENT_RE.subn(
lambda match: match.group(0).upper(), component
)
uri_bytes = component.encode("utf-8", "surrogatepass")
is_percent_encoded = percent_encodings == uri_bytes.count(b"%")
encoded_component = bytearray()
for i in range(0, len(uri_bytes)):
# Will return a single character bytestring on both Python 2 & 3
byte = uri_bytes[i : i + 1]
byte_ord = ord(byte)
if (is_percent_encoded and byte == b"%") or (
byte_ord < 128 and byte.decode() in allowed_chars
):
encoded_component += byte
continue
encoded_component.extend(b"%" + (hex(byte_ord)[2:].encode().zfill(2).upper()))
return encoded_component.decode(encoding)
def _remove_path_dot_segments(path):
# See http://tools.ietf.org/html/rfc3986#section-5.2.4 for pseudo-code
segments = path.split("/") # Turn the path into a list of segments
output = [] # Initialize the variable to use to store output
for segment in segments:
# '.' is the current directory, so ignore it, it is superfluous
if segment == ".":
continue
# Anything other than '..', should be appended to the output
elif segment != "..":
output.append(segment)
# In this case segment == '..', if we can, we should pop the last
# element
elif output:
output.pop()
# If the path starts with '/' and the output is empty or the first string
# is non-empty
if path.startswith("/") and (not output or output[0]):
output.insert(0, "")
# If the path starts with '/.' or '/..' ensure we add one more empty
# string to add a trailing '/'
if path.endswith(("/.", "/..")):
output.append("")
return "/".join(output)
def _normalize_host(host, scheme):
if host:
if isinstance(host, six.binary_type):
host = six.ensure_str(host)
if scheme in NORMALIZABLE_SCHEMES:
is_ipv6 = IPV6_ADDRZ_RE.match(host)
if is_ipv6:
match = ZONE_ID_RE.search(host)
if match:
start, end = match.span(1)
zone_id = host[start:end]
if zone_id.startswith("%25") and zone_id != "%25":
zone_id = zone_id[3:]
else:
zone_id = zone_id[1:]
zone_id = "%" + _encode_invalid_chars(zone_id, UNRESERVED_CHARS)
return host[:start].lower() + zone_id + host[end:]
else:
return host.lower()
elif not IPV4_RE.match(host):
return six.ensure_str(
b".".join([_idna_encode(label) for label in host.split(".")])
)
return host
def _idna_encode(name):
if name and any([ord(x) > 128 for x in name]):
try:
from pip._vendor import idna
except ImportError:
six.raise_from(
LocationParseError("Unable to parse URL without the 'idna' module"),
None,
)
try:
return idna.encode(name.lower(), strict=True, std3_rules=True)
except idna.IDNAError:
six.raise_from(
LocationParseError(u"Name '%s' is not a valid IDNA label" % name), None
)
return name.lower().encode("ascii")
def _encode_target(target):
"""Percent-encodes a request target so that there are no invalid characters"""
path, query = TARGET_RE.match(target).groups()
target = _encode_invalid_chars(path, PATH_CHARS)
query = _encode_invalid_chars(query, QUERY_CHARS)
if query is not None:
target += "?" + query
return target
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.
This parser is RFC 3986 compliant.
The parser logic and helper functions are based heavily on
work done in the ``rfc3986`` module.
:param str url: URL to parse into a :class:`.Url` namedtuple.
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', ...)
"""
if not url:
# Empty
return Url()
source_url = url
if not SCHEME_RE.search(url):
url = "//" + url
try:
scheme, authority, path, query, fragment = URI_RE.match(url).groups()
normalize_uri = scheme is None or scheme.lower() in NORMALIZABLE_SCHEMES
if scheme:
scheme = scheme.lower()
if authority:
auth, host, port = SUBAUTHORITY_RE.match(authority).groups()
if auth and normalize_uri:
auth = _encode_invalid_chars(auth, USERINFO_CHARS)
if port == "":
port = None
else:
auth, host, port = None, None, None
if port is not None:
port = int(port)
if not (0 <= port <= 65535):
raise LocationParseError(url)
host = _normalize_host(host, scheme)
if normalize_uri and path:
path = _remove_path_dot_segments(path)
path = _encode_invalid_chars(path, PATH_CHARS)
if normalize_uri and query:
query = _encode_invalid_chars(query, QUERY_CHARS)
if normalize_uri and fragment:
fragment = _encode_invalid_chars(fragment, FRAGMENT_CHARS)
except (ValueError, AttributeError):
return six.raise_from(LocationParseError(source_url), None)
# For the sake of backwards compatibility we put empty
# string values for path if there are any defined values
# beyond the path in the URL.
# TODO: Remove this when we break backwards compatibility.
if not path:
if query is not None or fragment is not None:
path = ""
else:
path = None
# Ensure that each part of the URL is a `str` for
# backwards compatibility.
if isinstance(url, six.text_type):
ensure_func = six.ensure_text
else:
ensure_func = six.ensure_str
def ensure_type(x):
return x if x is None else ensure_func(x)
return Url(
scheme=ensure_type(scheme),
auth=ensure_type(auth),
host=ensure_type(host),
port=port,
path=ensure_type(path),
query=ensure_type(query),
fragment=ensure_type(fragment),
)
def get_host(url):
"""
Deprecated. Use :func:`parse_url` instead.
"""
p = parse_url(url)
return p.scheme or "http", p.hostname, p.port
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