h/plugins/util/urlnorm.py

216 lines
8.2 KiB
Python

"""
URI Normalization function:
* Always provide the URI scheme in lowercase characters.
* Always provide the host, if any, in lowercase characters.
* Only perform percent-encoding where it is essential.
* Always use uppercase A-through-F characters when percent-encoding.
* Prevent dot-segments appearing in non-relative URI paths.
* For schemes that define a default authority, use an empty authority if the
default is desired.
* For schemes that define an empty path to be equivalent to a path of "/",
use "/".
* For schemes that define a port, use an empty port if the default is desired
* All portions of the URI must be utf-8 encoded NFC from Unicode strings
implements:
http://gbiv.com/protocols/uri/rev-2002/rfc2396bis.html#canonical-form
http://www.intertwingly.net/wiki/pie/PaceCanonicalIds
inspired by:
Tony J. Ibbs, http://starship.python.net/crew/tibs/python/tji_url.py
Mark Nottingham, http://www.mnot.net/python/urlnorm.py
"""
__license__ = "Python"
import re, unicodedata, urlparse
from urllib import quote, unquote
default_port = {
'ftp': 21,
'telnet': 23,
'http': 80,
'gopher': 70,
'news': 119,
'nntp': 119,
'prospero': 191,
'https': 443,
'snews': 563,
'snntp': 563,
}
def normalize(url):
"""Normalize a URL."""
scheme,auth,path,query,fragment = urlparse.urlsplit(url.strip())
(userinfo,host,port)=re.search('([^@]*@)?([^:]*):?(.*)',auth).groups()
# Always provide the URI scheme in lowercase characters.
scheme = scheme.lower()
# Always provide the host, if any, in lowercase characters.
host = host.lower()
if host and host[-1] == '.': host = host[:-1]
if host and host.startswith("www."):
if not scheme: scheme = "http"
host = host[4:]
elif path and path.startswith("www."):
if not scheme: scheme = "http"
path = path[4:]
# Only perform percent-encoding where it is essential.
# Always use uppercase A-through-F characters when percent-encoding.
# All portions of the URI must be utf-8 encoded NFC from Unicode strings
def clean(string):
string=unicode(unquote(string),'utf-8','replace')
return unicodedata.normalize('NFC',string).encode('utf-8')
path=quote(clean(path),"~:/?#[]@!$&'()*+,;=")
fragment=quote(clean(fragment),"~")
# note care must be taken to only encode & and = characters as values
query="&".join(["=".join([quote(clean(t) ,"~:/?#[]@!$'()*+,;=")
for t in q.split("=",1)]) for q in query.split("&")])
# Prevent dot-segments appearing in non-relative URI paths.
if scheme in ["","http","https","ftp","file"]:
output=[]
for input in path.split('/'):
if input=="":
if not output: output.append(input)
elif input==".":
pass
elif input=="..":
if len(output)>1: output.pop()
else:
output.append(input)
if input in ["",".",".."]: output.append("")
path='/'.join(output)
# For schemes that define a default authority, use an empty authority if
# the default is desired.
if userinfo in ["@",":@"]: userinfo=""
# For schemes that define an empty path to be equivalent to a path of "/",
# use "/".
if path=="" and scheme in ["http","https","ftp","file"]:
path="/"
# For schemes that define a port, use an empty port if the default is
# desired
if port and scheme in default_port.keys():
if port.isdigit():
port=str(int(port))
if int(port)==default_port[scheme]:
port = ''
# Put it all back together again
auth=(userinfo or "") + host
if port: auth+=":"+port
if url.endswith("#") and query=="" and fragment=="": path+="#"
return urlparse.urlunsplit((scheme,auth,path,query,fragment)).replace("http:///", "http://")
if __name__ == "__main__":
import unittest
suite = unittest.TestSuite()
""" from http://www.intertwingly.net/wiki/pie/PaceCanonicalIds """
tests= [
(False, "http://:@example.com/"),
(False, "http://@example.com/"),
(False, "http://example.com"),
(False, "HTTP://example.com/"),
(False, "http://EXAMPLE.COM/"),
(False, "http://example.com/%7Ejane"),
(False, "http://example.com/?q=%C7"),
(False, "http://example.com/?q=%5c"),
(False, "http://example.com/?q=C%CC%A7"),
(False, "http://example.com/a/../a/b"),
(False, "http://example.com/a/./b"),
(False, "http://example.com:80/"),
(True, "http://example.com/"),
(True, "http://example.com/?q=%C3%87"),
(True, "http://example.com/?q=%E2%85%A0"),
(True, "http://example.com/?q=%5C"),
(True, "http://example.com/~jane"),
(True, "http://example.com/a/b"),
(True, "http://example.com:8080/"),
(True, "http://user:password@example.com/"),
# from rfc2396bis
(True, "ftp://ftp.is.co.za/rfc/rfc1808.txt"),
(True, "http://www.ietf.org/rfc/rfc2396.txt"),
(True, "ldap://[2001:db8::7]/c=GB?objectClass?one"),
(True, "mailto:John.Doe@example.com"),
(True, "news:comp.infosystems.www.servers.unix"),
(True, "tel:+1-816-555-1212"),
(True, "telnet://192.0.2.16:80/"),
(True, "urn:oasis:names:specification:docbook:dtd:xml:4.1.2"),
# other
(True, "http://127.0.0.1/"),
(False, "http://127.0.0.1:80/"),
(True, "http://www.w3.org/2000/01/rdf-schema#"),
(False, "http://example.com:081/"),
]
def testcase(expected,value):
class test(unittest.TestCase):
def runTest(self):
assert (normalize(value)==value)==expected, \
(expected, value, normalize(value))
return test()
for (expected,value) in tests:
suite.addTest(testcase(expected,value))
""" mnot test suite; three tests updated for rfc2396bis. """
tests = {
'/foo/bar/.': '/foo/bar/',
'/foo/bar/./': '/foo/bar/',
'/foo/bar/..': '/foo/',
'/foo/bar/../': '/foo/',
'/foo/bar/../baz': '/foo/baz',
'/foo/bar/../..': '/',
'/foo/bar/../../': '/',
'/foo/bar/../../baz': '/baz',
'/foo/bar/../../../baz': '/baz', #was: '/../baz',
'/foo/bar/../../../../baz': '/baz',
'/./foo': '/foo',
'/../foo': '/foo', #was: '/../foo',
'/foo.': '/foo.',
'/.foo': '/.foo',
'/foo..': '/foo..',
'/..foo': '/..foo',
'/./../foo': '/foo', #was: '/../foo',
'/./foo/.': '/foo/',
'/foo/./bar': '/foo/bar',
'/foo/../bar': '/bar',
'/foo//': '/foo/',
'/foo///bar//': '/foo/bar/',
'http://www.foo.com:80/foo': 'http://www.foo.com/foo',
'http://www.foo.com:8000/foo': 'http://www.foo.com:8000/foo',
'http://www.foo.com./foo/bar.html': 'http://www.foo.com/foo/bar.html',
'http://www.foo.com.:81/foo': 'http://www.foo.com:81/foo',
'http://www.foo.com/%7ebar': 'http://www.foo.com/~bar',
'http://www.foo.com/%7Ebar': 'http://www.foo.com/~bar',
'ftp://user:pass@ftp.foo.net/foo/bar':
'ftp://user:pass@ftp.foo.net/foo/bar',
'http://USER:pass@www.Example.COM/foo/bar':
'http://USER:pass@www.example.com/foo/bar',
'http://www.example.com./': 'http://www.example.com/',
'-': '-',
}
def testcase(original,normalized):
class test(unittest.TestCase):
def runTest(self):
assert normalize(original)==normalized, \
(original, normalized, normalize(original))
return test()
for (original,normalized) in tests.items():
suite.addTest(testcase(original,normalized))
""" execute tests """
unittest.TextTestRunner().run(suite)