# Copyright (C) 2006-2010 Canonical Ltd
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
"""A collection of function for handling URL operations."""
import os
import re
import sys
from bzrlib.lazy_import import lazy_import
lazy_import(globals(), """
from posixpath import split as _posix_split, normpath as _posix_normpath
import urllib
import urlparse
from bzrlib import (
errors,
osutils,
)
""")
def basename(url, exclude_trailing_slash=True):
"""Return the last component of a URL.
:param url: The URL in question
:param exclude_trailing_slash: If the url looks like "path/to/foo/"
ignore the final slash and return 'foo' rather than ''
:return: Just the final component of the URL. This can return ''
if you don't exclude_trailing_slash, or if you are at the
root of the URL.
"""
return split(url, exclude_trailing_slash=exclude_trailing_slash)[1]
def dirname(url, exclude_trailing_slash=True):
"""Return the parent directory of the given path.
:param url: Relative or absolute URL
:param exclude_trailing_slash: Remove a final slash
(treat http://host/foo/ as http://host/foo, but
http://host/ stays http://host/)
:return: Everything in the URL except the last path chunk
"""
# TODO: jam 20060502 This was named dirname to be consistent
# with the os functions, but maybe "parent" would be better
return split(url, exclude_trailing_slash=exclude_trailing_slash)[0]
def escape(relpath):
"""Escape relpath to be a valid url."""
if isinstance(relpath, unicode):
relpath = relpath.encode('utf-8')
# After quoting and encoding, the path should be perfectly
# safe as a plain ASCII string, str() just enforces this
return str(urllib.quote(relpath, safe='/~'))
def file_relpath(base, path):
"""Compute just the relative sub-portion of a url
This assumes that both paths are already fully specified file:// URLs.
"""
if len(base) < MIN_ABS_FILEURL_LENGTH:
raise ValueError('Length of base (%r) must equal or'
' exceed the platform minimum url length (which is %d)' %
(base, MIN_ABS_FILEURL_LENGTH))
base = local_path_from_url(base)
path = local_path_from_url(path)
return escape(osutils.relpath(base, path))
def _find_scheme_and_separator(url):
"""Find the scheme separator (://) and the first path separator
This is just a helper functions for other path utilities.
It could probably be replaced by urlparse
"""
m = _url_scheme_re.match(url)
if not m:
return None, None
scheme = m.group('scheme')
path = m.group('path')
# Find the path separating slash
# (first slash after the ://)
first_path_slash = path.find('/')
if first_path_slash == -1:
return len(scheme), None
return len(scheme), first_path_slash+len(scheme)+3
def join(base, *args):
"""Create a URL by joining sections.
This will normalize '..', assuming that paths are absolute
(it assumes no symlinks in either path)
If any of *args is an absolute URL, it will be treated correctly.
Example:
join('http://foo', 'http://bar') => 'http://bar'
join('http://foo', 'bar') => 'http://foo/bar'
join('http://foo', 'bar', '../baz') => 'http://foo/baz'
"""
if not args:
return base
match = _url_scheme_re.match(base)
scheme = None
if match:
scheme = match.group('scheme')
path = match.group('path').split('/')
if path[-1:] == ['']:
# Strip off a trailing slash
# This helps both when we are at the root, and when
# 'base' has an extra slash at the end
path = path[:-1]
else:
path = base.split('/')
if scheme is not None and len(path) >= 1:
host = path[:1]
# the path should be represented as an abs path.
# we know this must be absolute because of the presence of a URL scheme.
remove_root = True
path = [''] + path[1:]
else:
# create an empty host, but dont alter the path - this might be a
# relative url fragment.
host = []
remove_root = False
for arg in args:
match = _url_scheme_re.match(arg)
if match:
# Absolute URL
scheme = match.group('scheme')
# this skips .. normalisation, making http://host/../../..
# be rather strange.
path = match.group('path').split('/')
# set the host and path according to new absolute URL, discarding
# any previous values.
# XXX: duplicates mess from earlier in this function. This URL
# manipulation code needs some cleaning up.
if scheme is not None and len(path) >= 1:
host = path[:1]
path = path[1:]
# url scheme implies absolute path.
path = [''] + path
else:
# no url scheme we take the path as is.
host = []
else:
path = '/'.join(path)
path = joinpath(path, arg)
path = path.split('/')
if remove_root and path[0:1] == ['']:
del path[0]
if host:
# Remove the leading slash from the path, so long as it isn't also the
# trailing slash, which we want to keep if present.
if path and path[0] == '' and len(path) > 1:
del path[0]
path = host + path
if scheme is None:
return '/'.join(path)
return scheme + '://' + '/'.join(path)
def joinpath(base, *args):
"""Join URL path segments to a URL path segment.
This is somewhat like osutils.joinpath, but intended for URLs.
XXX: this duplicates some normalisation logic, and also duplicates a lot of
path handling logic that already exists in some Transport implementations.
We really should try to have exactly one place in the code base responsible
for combining paths of URLs.
"""
path = base.split('/')
if len(path) > 1 and path[-1] == '':
#If the path ends in a trailing /, remove it.
path.pop()
for arg in args:
if arg.startswith('/'):
path = []
for chunk in arg.split('/'):
if chunk == '.':
continue
elif chunk == '..':
if path == ['']:
raise errors.InvalidURLJoin('Cannot go above root',
base, args)
path.pop()
else:
path.append(chunk)
if path == ['']:
return '/'
else:
return '/'.join(path)
# jam 20060502 Sorted to 'l' because the final target is 'local_path_from_url'
def _posix_local_path_from_url(url):
"""Convert a url like file:///path/to/foo into /path/to/foo"""
file_localhost_prefix = 'file://localhost/'
if url.startswith(file_localhost_prefix):
path = url[len(file_localhost_prefix) - 1:]
elif not url.startswith('file:///'):
raise errors.InvalidURL(
url, 'local urls must start with file:/// or file://localhost/')
else:
path = url[len('file://'):]
# We only strip off 2 slashes
return unescape(path)
def _posix_local_path_to_url(path):
"""Convert a local path like ./foo into a URL like file:///path/to/foo
This also handles transforming escaping unicode characters, etc.
"""
# importing directly from posixpath allows us to test this
# on non-posix platforms
return 'file://' + escape(_posix_normpath(
osutils._posix_abspath(path)))
def _win32_local_path_from_url(url):
"""Convert a url like file:///C:/path/to/foo into C:/path/to/foo"""
if not url.startswith('file://'):
raise errors.InvalidURL(url, 'local urls must start with file:///, '
'UNC path urls must start with file://')
# We strip off all 3 slashes
win32_url = url[len('file:'):]
# check for UNC path: //HOST/path
if not win32_url.startswith('///'):
if (win32_url[2] == '/'
or win32_url[3] in '|:'):
raise errors.InvalidURL(url, 'Win32 UNC path urls'
' have form file://HOST/path')
return unescape(win32_url)
# allow empty paths so we can serve all roots
if win32_url == '///':
return '/'
# usual local path with drive letter
if (win32_url[3] not in ('abcdefghijklmnopqrstuvwxyz'
'ABCDEFGHIJKLMNOPQRSTUVWXYZ')
or win32_url[4] not in '|:'
or win32_url[5] != '/'):
raise errors.InvalidURL(url, 'Win32 file urls start with'
' file:///x:/, where x is a valid drive letter')
return win32_url[3].upper() + u':' + unescape(win32_url[5:])
def _win32_local_path_to_url(path):
"""Convert a local path like ./foo into a URL like file:///C:/path/to/foo
This also handles transforming escaping unicode characters, etc.
"""
# importing directly from ntpath allows us to test this
# on non-win32 platform
# FIXME: It turns out that on nt, ntpath.abspath uses nt._getfullpathname
# which actually strips trailing space characters.
# The worst part is that under linux ntpath.abspath has different
# semantics, since 'nt' is not an available module.
if path == '/':
return 'file:///'
win32_path = osutils._win32_abspath(path)
# check for UNC path \\HOST\path
if win32_path.startswith('//'):
return 'file:' + escape(win32_path)
return ('file:///' + str(win32_path[0].upper()) + ':' +
escape(win32_path[2:]))
local_path_to_url = _posix_local_path_to_url
local_path_from_url = _posix_local_path_from_url
MIN_ABS_FILEURL_LENGTH = len('file:///')
WIN32_MIN_ABS_FILEURL_LENGTH = len('file:///C:/')
if sys.platform == 'win32':
local_path_to_url = _win32_local_path_to_url
local_path_from_url = _win32_local_path_from_url
MIN_ABS_FILEURL_LENGTH = WIN32_MIN_ABS_FILEURL_LENGTH
_url_scheme_re = re.compile(r'^(?P<scheme>[^:/]{2,})://(?P<path>.*)$')
_url_hex_escapes_re = re.compile(r'(%[0-9a-fA-F]{2})')
def _unescape_safe_chars(matchobj):
"""re.sub callback to convert hex-escapes to plain characters (if safe).
e.g. '%7E' will be converted to '~'.
"""
hex_digits = matchobj.group(0)[1:]
char = chr(int(hex_digits, 16))
if char in _url_dont_escape_characters:
return char
else:
return matchobj.group(0).upper()
def normalize_url(url):
"""Make sure that a path string is in fully normalized URL form.
This handles URLs which have unicode characters, spaces,
special characters, etc.
It has two basic modes of operation, depending on whether the
supplied string starts with a url specifier (scheme://) or not.
If it does not have a specifier it is considered a local path,
and will be converted into a file:/// url. Non-ascii characters
will be encoded using utf-8.
If it does have a url specifier, it will be treated as a "hybrid"
URL. Basically, a URL that should have URL special characters already
escaped (like +?&# etc), but may have unicode characters, etc
which would not be valid in a real URL.
:param url: Either a hybrid URL or a local path
:return: A normalized URL which only includes 7-bit ASCII characters.
"""
m = _url_scheme_re.match(url)
if not m:
return local_path_to_url(url)
scheme = m.group('scheme')
path = m.group('path')
if not isinstance(url, unicode):
for c in url:
if c not in _url_safe_characters:
raise errors.InvalidURL(url, 'URLs can only contain specific'
' safe characters (not %r)' % c)
path = _url_hex_escapes_re.sub(_unescape_safe_chars, path)
return str(scheme + '://' + ''.join(path))
# We have a unicode (hybrid) url
path_chars = list(path)
for i in xrange(len(path_chars)):
if path_chars[i] not in _url_safe_characters:
chars = path_chars[i].encode('utf-8')
path_chars[i] = ''.join(
['%%%02X' % ord(c) for c in path_chars[i].encode('utf-8')])
path = ''.join(path_chars)
path = _url_hex_escapes_re.sub(_unescape_safe_chars, path)
return str(scheme + '://' + path)
def relative_url(base, other):
"""Return a path to other from base.
If other is unrelated to base, return other. Else return a relative path.
This assumes no symlinks as part of the url.
"""
dummy, base_first_slash = _find_scheme_and_separator(base)
if base_first_slash is None:
return other
dummy, other_first_slash = _find_scheme_and_separator(other)
if other_first_slash is None:
return other
# this takes care of differing schemes or hosts
base_scheme = base[:base_first_slash]
other_scheme = other[:other_first_slash]
if base_scheme != other_scheme:
return other
elif sys.platform == 'win32' and base_scheme == 'file://':
base_drive = base[base_first_slash+1:base_first_slash+3]
other_drive = other[other_first_slash+1:other_first_slash+3]
if base_drive != other_drive:
return other
base_path = base[base_first_slash+1:]
other_path = other[other_first_slash+1:]
if base_path.endswith('/'):
base_path = base_path[:-1]
base_sections = base_path.split('/')
other_sections = other_path.split('/')
if base_sections == ['']:
base_sections = []
if other_sections == ['']:
other_sections = []
output_sections = []
for b, o in zip(base_sections, other_sections):
if b != o:
break
output_sections.append(b)
match_len = len(output_sections)
output_sections = ['..' for x in base_sections[match_len:]]
output_sections.extend(other_sections[match_len:])
return "/".join(output_sections) or "."
def _win32_extract_drive_letter(url_base, path):
"""On win32 the drive letter needs to be added to the url base."""
# Strip off the drive letter
# path is currently /C:/foo
if len(path) < 3 or path[2] not in ':|' or path[3] != '/':
raise errors.InvalidURL(url_base + path,
'win32 file:/// paths need a drive letter')
url_base += path[0:3] # file:// + /C:
path = path[3:] # /foo
return url_base, path
def split(url, exclude_trailing_slash=True):
"""Split a URL into its parent directory and a child directory.
:param url: A relative or absolute URL
:param exclude_trailing_slash: Strip off a final '/' if it is part
of the path (but not if it is part of the protocol specification)
:return: (parent_url, child_dir). child_dir may be the empty string if we're at
the root.
"""
scheme_loc, first_path_slash = _find_scheme_and_separator(url)
if first_path_slash is None:
# We have either a relative path, or no separating slash
if scheme_loc is None:
# Relative path
if exclude_trailing_slash and url.endswith('/'):
url = url[:-1]
return _posix_split(url)
else:
# Scheme with no path
return url, ''
# We have a fully defined path
url_base = url[:first_path_slash] # http://host, file://
path = url[first_path_slash:] # /file/foo
if sys.platform == 'win32' and url.startswith('file:///'):
# Strip off the drive letter
# url_base is currently file://
# path is currently /C:/foo
url_base, path = _win32_extract_drive_letter(url_base, path)
# now it should be file:///C: and /foo
if exclude_trailing_slash and len(path) > 1 and path.endswith('/'):
path = path[:-1]
head, tail = _posix_split(path)
return url_base + head, tail
def _win32_strip_local_trailing_slash(url):
"""Strip slashes after the drive letter"""
if len(url) > WIN32_MIN_ABS_FILEURL_LENGTH:
return url[:-1]
else:
return url
def strip_trailing_slash(url):
"""Strip trailing slash, except for root paths.
The definition of 'root path' is platform-dependent.
This assumes that all URLs are valid netloc urls, such that they
form:
scheme://host/path
It searches for ://, and then refuses to remove the next '/'.
It can also handle relative paths
Examples:
path/to/foo => path/to/foo
path/to/foo/ => path/to/foo
http://host/path/ => http://host/path
http://host/path => http://host/path
http://host/ => http://host/
file:/// => file:///
file:///foo/ => file:///foo
# This is unique on win32 platforms, and is the only URL
# format which does it differently.
file:///c|/ => file:///c:/
"""
if not url.endswith('/'):
# Nothing to do
return url
if sys.platform == 'win32' and url.startswith('file://'):
return _win32_strip_local_trailing_slash(url)
scheme_loc, first_path_slash = _find_scheme_and_separator(url)
if scheme_loc is None:
# This is a relative path, as it has no scheme
# so just chop off the last character
return url[:-1]
if first_path_slash is None or first_path_slash == len(url)-1:
# Don't chop off anything if the only slash is the path
# separating slash
return url
return url[:-1]
def unescape(url):
"""Unescape relpath from url format.
This returns a Unicode path from a URL
"""
# jam 20060427 URLs are supposed to be ASCII only strings
# If they are passed in as unicode, urllib.unquote
# will return a UNICODE string, which actually contains
# utf-8 bytes. So we have to ensure that they are
# plain ASCII strings, or the final .decode will
# try to encode the UNICODE => ASCII, and then decode
# it into utf-8.
try:
url = str(url)
except UnicodeError, e:
raise errors.InvalidURL(url, 'URL was not a plain ASCII url: %s' % (e,))
unquoted = urllib.unquote(url)
try:
unicode_path = unquoted.decode('utf-8')
except UnicodeError, e:
raise errors.InvalidURL(url, 'Unable to encode the URL as utf-8: %s' % (e,))
return unicode_path
# These are characters that if escaped, should stay that way
_no_decode_chars = ';/?:@&=+$,#'
_no_decode_ords = [ord(c) for c in _no_decode_chars]
_no_decode_hex = (['%02x' % o for o in _no_decode_ords]
+ ['%02X' % o for o in _no_decode_ords])
_hex_display_map = dict(([('%02x' % o, chr(o)) for o in range(256)]
+ [('%02X' % o, chr(o)) for o in range(256)]))
#These entries get mapped to themselves
_hex_display_map.update((hex,'%'+hex) for hex in _no_decode_hex)
# These characters shouldn't be percent-encoded, and it's always safe to
# unencode them if they are.
_url_dont_escape_characters = set(
"abcdefghijklmnopqrstuvwxyz" # Lowercase alpha
"ABCDEFGHIJKLMNOPQRSTUVWXYZ" # Uppercase alpha
"0123456789" # Numbers
"-._~" # Unreserved characters
)
# These characters should not be escaped
_url_safe_characters = set(
"abcdefghijklmnopqrstuvwxyz" # Lowercase alpha
"ABCDEFGHIJKLMNOPQRSTUVWXYZ" # Uppercase alpha
"0123456789" # Numbers
"_.-!~*'()" # Unreserved characters
"/;?:@&=+$," # Reserved characters
"%#" # Extra reserved characters
)
def unescape_for_display(url, encoding):
"""Decode what you can for a URL, so that we get a nice looking path.
This will turn file:// urls into local paths, and try to decode
any portions of a http:// style url that it can.
Any sections of the URL which can't be represented in the encoding or
need to stay as escapes are left alone.
:param url: A 7-bit ASCII URL
:param encoding: The final output encoding
:return: A unicode string which can be safely encoded into the
specified encoding.
"""
if encoding is None:
raise ValueError('you cannot specify None for the display encoding')
if url.startswith('file://'):
try:
path = local_path_from_url(url)
path.encode(encoding)
return path
except UnicodeError:
return url
# Split into sections to try to decode utf-8
res = url.split('/')
for i in xrange(1, len(res)):
escaped_chunks = res[i].split('%')
for j in xrange(1, len(escaped_chunks)):
item = escaped_chunks[j]
try:
escaped_chunks[j] = _hex_display_map[item[:2]] + item[2:]
except KeyError:
# Put back the percent symbol
escaped_chunks[j] = '%' + item
except UnicodeDecodeError:
escaped_chunks[j] = unichr(int(item[:2], 16)) + item[2:]
unescaped = ''.join(escaped_chunks)
try:
decoded = unescaped.decode('utf-8')
except UnicodeDecodeError:
# If this path segment cannot be properly utf-8 decoded
# after doing unescaping we will just leave it alone
pass
else:
try:
decoded.encode(encoding)
except UnicodeEncodeError:
# If this chunk cannot be encoded in the local
# encoding, then we should leave it alone
pass
else:
# Otherwise take the url decoded one
res[i] = decoded
return u'/'.join(res)
def derive_to_location(from_location):
"""Derive a TO_LOCATION given a FROM_LOCATION.
The normal case is a FROM_LOCATION of http://foo/bar => bar.
The Right Thing for some logical destinations may differ though
because no / may be present at all. In that case, the result is
the full name without the scheme indicator, e.g. lp:foo-bar => foo-bar.
This latter case also applies when a Windows drive
is used without a path, e.g. c:foo-bar => foo-bar.
If no /, path separator or : is found, the from_location is returned.
"""
if from_location.find("/") >= 0 or from_location.find(os.sep) >= 0:
return os.path.basename(from_location.rstrip("/\\"))
else:
sep = from_location.find(":")
if sep > 0:
return from_location[sep+1:]
else:
return from_location
def _is_absolute(url):
return (osutils.pathjoin('/foo', url) == url)
def rebase_url(url, old_base, new_base):
"""Convert a relative path from an old base URL to a new base URL.
The result will be a relative path.
Absolute paths and full URLs are returned unaltered.
"""
scheme, separator = _find_scheme_and_separator(url)
if scheme is not None:
return url
if _is_absolute(url):
return url
old_parsed = urlparse.urlparse(old_base)
new_parsed = urlparse.urlparse(new_base)
if (old_parsed[:2]) != (new_parsed[:2]):
raise errors.InvalidRebaseURLs(old_base, new_base)
return determine_relative_path(new_parsed[2],
join(old_parsed[2], url))
def determine_relative_path(from_path, to_path):
"""Determine a relative path from from_path to to_path."""
from_segments = osutils.splitpath(from_path)
to_segments = osutils.splitpath(to_path)
count = -1
for count, (from_element, to_element) in enumerate(zip(from_segments,
to_segments)):
if from_element != to_element:
break
else:
count += 1
unique_from = from_segments[count:]
unique_to = to_segments[count:]
segments = (['..'] * len(unique_from) + unique_to)
if len(segments) == 0:
return '.'
return osutils.pathjoin(*segments)
def parse_url(url):
"""Extract the server address, the credentials and the path from the url.
user, password, host and path should be quoted if they contain reserved
chars.
:param url: an quoted url
:return: (scheme, user, password, host, port, path) tuple, all fields
are unquoted.
"""
if isinstance(url, unicode):
raise errors.InvalidURL('should be ascii:\n%r' % url)
url = url.encode('utf-8')
(scheme, netloc, path, params,
query, fragment) = urlparse.urlparse(url, allow_fragments=False)
user = password = host = port = None
if '@' in netloc:
user, host = netloc.rsplit('@', 1)
if ':' in user:
user, password = user.split(':', 1)
password = urllib.unquote(password)
user = urllib.unquote(user)
else:
host = netloc
if ':' in host and not (host[0] == '[' and host[-1] == ']'): #there *is* port
host, port = host.rsplit(':',1)
try:
port = int(port)
except ValueError:
raise errors.InvalidURL('invalid port number %s in url:\n%s' %
(port, url))
if host != "" and host[0] == '[' and host[-1] == ']': #IPv6
host = host[1:-1]
host = urllib.unquote(host)
path = urllib.unquote(path)
return (scheme, user, password, host, port, path)
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