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- """Parse (absolute and relative) URLs.
-
- See RFC 1808: "Relative Uniform Resource Locators", by R. Fielding,
- UC Irvine, June 1995.
- """
-
- __all__ = ["urlparse", "urlunparse", "urljoin", "urldefrag",
- "urlsplit", "urlunsplit", "parse_qs", "parse_qsl"]
-
- # A classification of schemes ('' means apply by default)
- uses_relative = ['ftp', 'http', 'gopher', 'nntp', 'imap',
- 'wais', 'file', 'https', 'shttp', 'mms',
- 'prospero', 'rtsp', 'rtspu', '', 'sftp']
- uses_netloc = ['ftp', 'http', 'gopher', 'nntp', 'telnet',
- 'imap', 'wais', 'file', 'mms', 'https', 'shttp',
- 'snews', 'prospero', 'rtsp', 'rtspu', 'rsync', '',
- 'svn', 'svn+ssh', 'sftp']
- non_hierarchical = ['gopher', 'hdl', 'mailto', 'news',
- 'telnet', 'wais', 'imap', 'snews', 'sip', 'sips']
- uses_params = ['ftp', 'hdl', 'prospero', 'http', 'imap',
- 'https', 'shttp', 'rtsp', 'rtspu', 'sip', 'sips',
- 'mms', '', 'sftp']
- uses_query = ['http', 'wais', 'imap', 'https', 'shttp', 'mms',
- 'gopher', 'rtsp', 'rtspu', 'sip', 'sips', '']
- uses_fragment = ['ftp', 'hdl', 'http', 'gopher', 'news',
- 'nntp', 'wais', 'https', 'shttp', 'snews',
- 'file', 'prospero', '']
-
- # Characters valid in scheme names
- scheme_chars = ('abcdefghijklmnopqrstuvwxyz'
- 'ABCDEFGHIJKLMNOPQRSTUVWXYZ'
- '0123456789'
- '+-.')
-
- MAX_CACHE_SIZE = 20
- _parse_cache = {}
-
- def clear_cache():
- """Clear the parse cache."""
- _parse_cache.clear()
-
-
- class ResultMixin(object):
- """Shared methods for the parsed result objects."""
-
- @property
- def username(self):
- netloc = self.netloc
- if "@" in netloc:
- userinfo = netloc.rsplit("@", 1)[0]
- if ":" in userinfo:
- userinfo = userinfo.split(":", 1)[0]
- return userinfo
- return None
-
- @property
- def password(self):
- netloc = self.netloc
- if "@" in netloc:
- userinfo = netloc.rsplit("@", 1)[0]
- if ":" in userinfo:
- return userinfo.split(":", 1)[1]
- return None
-
- @property
- def hostname(self):
- netloc = self.netloc
- if "@" in netloc:
- netloc = netloc.rsplit("@", 1)[1]
- if ":" in netloc:
- netloc = netloc.split(":", 1)[0]
- return netloc.lower() or None
-
- @property
- def port(self):
- netloc = self.netloc
- if "@" in netloc:
- netloc = netloc.rsplit("@", 1)[1]
- if ":" in netloc:
- port = netloc.split(":", 1)[1]
- return int(port, 10)
- return None
-
- from collections import namedtuple
-
- class SplitResult(namedtuple('SplitResult', 'scheme netloc path query fragment'), ResultMixin):
-
- __slots__ = ()
-
- def geturl(self):
- return urlunsplit(self)
-
-
- class ParseResult(namedtuple('ParseResult', 'scheme netloc path params query fragment'), ResultMixin):
-
- __slots__ = ()
-
- def geturl(self):
- return urlunparse(self)
-
-
- def urlparse(url, scheme='', allow_fragments=True):
- """Parse a URL into 6 components:
- <scheme>://<netloc>/<path>;<params>?<query>#<fragment>
- Return a 6-tuple: (scheme, netloc, path, params, query, fragment).
- Note that we don't break the components up in smaller bits
- (e.g. netloc is a single string) and we don't expand % escapes."""
- tuple = urlsplit(url, scheme, allow_fragments)
- scheme, netloc, url, query, fragment = tuple
- if scheme in uses_params and ';' in url:
- url, params = _splitparams(url)
- else:
- params = ''
- return ParseResult(scheme, netloc, url, params, query, fragment)
-
- def _splitparams(url):
- if '/' in url:
- i = url.find(';', url.rfind('/'))
- if i < 0:
- return url, ''
- else:
- i = url.find(';')
- return url[:i], url[i+1:]
-
- def _splitnetloc(url, start=0):
- delim = len(url) # position of end of domain part of url, default is end
- for c in '/?#': # look for delimiters; the order is NOT important
- wdelim = url.find(c, start) # find first of this delim
- if wdelim >= 0: # if found
- delim = min(delim, wdelim) # use earliest delim position
- return url[start:delim], url[delim:] # return (domain, rest)
-
- def urlsplit(url, scheme='', allow_fragments=True):
- """Parse a URL into 5 components:
- <scheme>://<netloc>/<path>?<query>#<fragment>
- Return a 5-tuple: (scheme, netloc, path, query, fragment).
- Note that we don't break the components up in smaller bits
- (e.g. netloc is a single string) and we don't expand % escapes."""
- allow_fragments = bool(allow_fragments)
- key = url, scheme, allow_fragments, type(url), type(scheme)
- cached = _parse_cache.get(key, None)
- if cached:
- return cached
- if len(_parse_cache) >= MAX_CACHE_SIZE: # avoid runaway growth
- clear_cache()
- netloc = query = fragment = ''
- i = url.find(':')
- if i > 0:
- if url[:i] == 'http': # optimize the common case
- scheme = url[:i].lower()
- url = url[i+1:]
- if url[:2] == '//':
- netloc, url = _splitnetloc(url, 2)
- if allow_fragments and '#' in url:
- url, fragment = url.split('#', 1)
- if '?' in url:
- url, query = url.split('?', 1)
- v = SplitResult(scheme, netloc, url, query, fragment)
- _parse_cache[key] = v
- return v
- for c in url[:i]:
- if c not in scheme_chars:
- break
- else:
- scheme, url = url[:i].lower(), url[i+1:]
-
- if url[:2] == '//':
- netloc, url = _splitnetloc(url, 2)
- if allow_fragments and scheme in uses_fragment and '#' in url:
- url, fragment = url.split('#', 1)
- if scheme in uses_query and '?' in url:
- url, query = url.split('?', 1)
- v = SplitResult(scheme, netloc, url, query, fragment)
- _parse_cache[key] = v
- return v
-
- def urlunparse(data):
- """Put a parsed URL back together again. This may result in a
- slightly different, but equivalent URL, if the URL that was parsed
- originally had redundant delimiters, e.g. a ? with an empty query
- (the draft states that these are equivalent)."""
- scheme, netloc, url, params, query, fragment = data
- if params:
- url = "%s;%s" % (url, params)
- return urlunsplit((scheme, netloc, url, query, fragment))
-
- def urlunsplit(data):
- scheme, netloc, url, query, fragment = data
- if netloc or (scheme and scheme in uses_netloc and url[:2] != '//'):
- if url and url[:1] != '/': url = '/' + url
- url = '//' + (netloc or '') + url
- if scheme:
- url = scheme + ':' + url
- if query:
- url = url + '?' + query
- if fragment:
- url = url + '#' + fragment
- return url
-
- def urljoin(base, url, allow_fragments=True):
- """Join a base URL and a possibly relative URL to form an absolute
- interpretation of the latter."""
- if not base:
- return url
- if not url:
- return base
- bscheme, bnetloc, bpath, bparams, bquery, bfragment = \
- urlparse(base, '', allow_fragments)
- scheme, netloc, path, params, query, fragment = \
- urlparse(url, bscheme, allow_fragments)
- if scheme != bscheme or scheme not in uses_relative:
- return url
- if scheme in uses_netloc:
- if netloc:
- return urlunparse((scheme, netloc, path,
- params, query, fragment))
- netloc = bnetloc
- if path[:1] == '/':
- return urlunparse((scheme, netloc, path,
- params, query, fragment))
- if not path:
- path = bpath
- if not params:
- params = bparams
- else:
- path = path[:-1]
- return urlunparse((scheme, netloc, path,
- params, query, fragment))
- if not query:
- query = bquery
- return urlunparse((scheme, netloc, path,
- params, query, fragment))
- segments = bpath.split('/')[:-1] + path.split('/')
- # XXX The stuff below is bogus in various ways...
- if segments[-1] == '.':
- segments[-1] = ''
- while '.' in segments:
- segments.remove('.')
- while 1:
- i = 1
- n = len(segments) - 1
- while i < n:
- if (segments[i] == '..'
- and segments[i-1] not in ('', '..')):
- del segments[i-1:i+1]
- break
- i = i+1
- else:
- break
- if segments == ['', '..']:
- segments[-1] = ''
- elif len(segments) >= 2 and segments[-1] == '..':
- segments[-2:] = ['']
- return urlunparse((scheme, netloc, '/'.join(segments),
- params, query, fragment))
-
- def urldefrag(url):
- """Removes any existing fragment from URL.
-
- Returns a tuple of the defragmented URL and the fragment. If
- the URL contained no fragments, the second element is the
- empty string.
- """
- if '#' in url:
- s, n, p, a, q, frag = urlparse(url)
- defrag = urlunparse((s, n, p, a, q, ''))
- return defrag, frag
- else:
- return url, ''
-
- # unquote method for parse_qs and parse_qsl
- # Cannot use directly from urllib as it would create circular reference.
- # urllib uses urlparse methods ( urljoin)
-
- _hextochr = dict(('%02x' % i, chr(i)) for i in range(256))
- _hextochr.update(('%02X' % i, chr(i)) for i in range(256))
-
- def unquote(s):
- """unquote('abc%20def') -> 'abc def'."""
- res = s.split('%')
- for i in xrange(1, len(res)):
- item = res[i]
- try:
- res[i] = _hextochr[item[:2]] + item[2:]
- except KeyError:
- res[i] = '%' + item
- except UnicodeDecodeError:
- res[i] = unichr(int(item[:2], 16)) + item[2:]
- return "".join(res)
-
- def parse_qs(qs, keep_blank_values=0, strict_parsing=0):
- """Parse a query given as a string argument.
-
- Arguments:
-
- qs: URL-encoded query string to be parsed
-
- keep_blank_values: flag indicating whether blank values in
- URL encoded queries should be treated as blank strings.
- A true value indicates that blanks should be retained as
- blank strings. The default false value indicates that
- blank values are to be ignored and treated as if they were
- not included.
-
- strict_parsing: flag indicating what to do with parsing errors.
- If false (the default), errors are silently ignored.
- If true, errors raise a ValueError exception.
- """
- dict = {}
- for name, value in parse_qsl(qs, keep_blank_values, strict_parsing):
- if name in dict:
- dict[name].append(value)
- else:
- dict[name] = [value]
- return dict
-
- def parse_qsl(qs, keep_blank_values=0, strict_parsing=0):
- """Parse a query given as a string argument.
-
- Arguments:
-
- qs: URL-encoded query string to be parsed
-
- keep_blank_values: flag indicating whether blank values in
- URL encoded queries should be treated as blank strings. A
- true value indicates that blanks should be retained as blank
- strings. The default false value indicates that blank values
- are to be ignored and treated as if they were not included.
-
- strict_parsing: flag indicating what to do with parsing errors. If
- false (the default), errors are silently ignored. If true,
- errors raise a ValueError exception.
-
- Returns a list, as G-d intended.
- """
- pairs = [s2 for s1 in qs.split('&') for s2 in s1.split(';')]
- r = []
- for name_value in pairs:
- if not name_value and not strict_parsing:
- continue
- nv = name_value.split('=', 1)
- if len(nv) != 2:
- if strict_parsing:
- raise ValueError, "bad query field: %r" % (name_value,)
- # Handle case of a control-name with no equal sign
- if keep_blank_values:
- nv.append('')
- else:
- continue
- if len(nv[1]) or keep_blank_values:
- name = unquote(nv[0].replace('+', ' '))
- value = unquote(nv[1].replace('+', ' '))
- r.append((name, value))
-
- return r
-
-
- test_input = """
- http://a/b/c/d
-
- g:h = <URL:g:h>
- http:g = <URL:http://a/b/c/g>
- http: = <URL:http://a/b/c/d>
- g = <URL:http://a/b/c/g>
- ./g = <URL:http://a/b/c/g>
- g/ = <URL:http://a/b/c/g/>
- /g = <URL:http://a/g>
- //g = <URL:http://g>
- ?y = <URL:http://a/b/c/d?y>
- g?y = <URL:http://a/b/c/g?y>
- g?y/./x = <URL:http://a/b/c/g?y/./x>
- . = <URL:http://a/b/c/>
- ./ = <URL:http://a/b/c/>
- .. = <URL:http://a/b/>
- ../ = <URL:http://a/b/>
- ../g = <URL:http://a/b/g>
- ../.. = <URL:http://a/>
- ../../g = <URL:http://a/g>
- ../../../g = <URL:http://a/../g>
- ./../g = <URL:http://a/b/g>
- ./g/. = <URL:http://a/b/c/g/>
- /./g = <URL:http://a/./g>
- g/./h = <URL:http://a/b/c/g/h>
- g/../h = <URL:http://a/b/c/h>
- http:g = <URL:http://a/b/c/g>
- http: = <URL:http://a/b/c/d>
- http:?y = <URL:http://a/b/c/d?y>
- http:g?y = <URL:http://a/b/c/g?y>
- http:g?y/./x = <URL:http://a/b/c/g?y/./x>
- """
-
- def test():
- import sys
- base = ''
- if sys.argv[1:]:
- fn = sys.argv[1]
- if fn == '-':
- fp = sys.stdin
- else:
- fp = open(fn)
- else:
- try:
- from cStringIO import StringIO
- except ImportError:
- from StringIO import StringIO
- fp = StringIO(test_input)
- for line in fp:
- words = line.split()
- if not words:
- continue
- url = words[0]
- parts = urlparse(url)
- print '%-10s : %s' % (url, parts)
- abs = urljoin(base, url)
- if not base:
- base = abs
- wrapped = '<URL:%s>' % abs
- print '%-10s = %s' % (url, wrapped)
- if len(words) == 3 and words[1] == '=':
- if wrapped != words[2]:
- print 'EXPECTED', words[2], '!!!!!!!!!!'
-
- if __name__ == '__main__':
- test()
-