install/python-installer/scripts/httplib2/iri2uri.py

"""
iri2uri

Copyright (c) 2006 by Joe Gregorio

Permission is hereby granted, free of charge, to any person
obtaining a copy of this software and associated documentation
files (the "Software"), to deal in the Software without restriction,
including without limitation the rights to use, copy, modify, merge,
publish, distribute, sublicense, and/or sell copies of the Software,
and to permit persons to whom the Software is furnished to do so,
subject to the following conditions:

The above copyright notice and this permission notice shall be
included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.

Converts an IRI to a URI.

"""
__author__ = "Joe Gregorio (joe@bitworking.org)"
__copyright__ = "Copyright 2006, Joe Gregorio"
__contributors__ = []
__version__ = "1.0.0"
__license__ = "MIT"
__history__ = """
"""

import urlparse


# Convert an IRI to a URI following the rules in RFC 3987
# 
# The characters we need to enocde and escape are defined in the spec:
#
# iprivate =  %xE000-F8FF / %xF0000-FFFFD / %x100000-10FFFD
# ucschar = %xA0-D7FF / %xF900-FDCF / %xFDF0-FFEF
#         / %x10000-1FFFD / %x20000-2FFFD / %x30000-3FFFD
#         / %x40000-4FFFD / %x50000-5FFFD / %x60000-6FFFD
#         / %x70000-7FFFD / %x80000-8FFFD / %x90000-9FFFD
#         / %xA0000-AFFFD / %xB0000-BFFFD / %xC0000-CFFFD
#         / %xD0000-DFFFD / %xE1000-EFFFD

escape_range = [
   (0xA0, 0xD7FF ),
   (0xE000, 0xF8FF ),
   (0xF900, 0xFDCF ),
   (0xFDF0, 0xFFEF),
   (0x10000, 0x1FFFD ),
   (0x20000, 0x2FFFD ),
   (0x30000, 0x3FFFD),
   (0x40000, 0x4FFFD ),
   (0x50000, 0x5FFFD ),
   (0x60000, 0x6FFFD),
   (0x70000, 0x7FFFD ),
   (0x80000, 0x8FFFD ),
   (0x90000, 0x9FFFD),
   (0xA0000, 0xAFFFD ),
   (0xB0000, 0xBFFFD ),
   (0xC0000, 0xCFFFD),
   (0xD0000, 0xDFFFD ),
   (0xE1000, 0xEFFFD),
   (0xF0000, 0xFFFFD ),
   (0x100000, 0x10FFFD)
]
 
def encode(c):
    retval = c
    i = ord(c)
    for low, high in escape_range:
        if i < low:
            break
        if i >= low and i <= high:
            retval = "".join(["%%%2X" % ord(o) for o in c.encode('utf-8')])
            break
    return retval


def iri2uri(uri):
    """Convert an IRI to a URI. Note that IRIs must be 
    passed in a unicode strings. That is, do not utf-8 encode
    the IRI before passing it into the function.""" 
    if isinstance(uri ,unicode):
        (scheme, authority, path, query, fragment) = urlparse.urlsplit(uri)
        authority = authority.encode('idna')
        # For each character in 'ucschar' or 'iprivate'
        #  1. encode as utf-8
        #  2. then %-encode each octet of that utf-8 
        uri = urlparse.urlunsplit((scheme, authority, path, query, fragment))
        uri = "".join([encode(c) for c in uri])
    return uri
        
if __name__ == "__main__":
    import unittest

    class Test(unittest.TestCase):

        def test_uris(self):
            """Test that URIs are invariant under the transformation."""
            invariant = [ 
                u"ftp://ftp.is.co.za/rfc/rfc1808.txt",
                u"http://www.ietf.org/rfc/rfc2396.txt",
                u"ldap://[2001:db8::7]/c=GB?objectClass?one",
                u"mailto:John.Doe@example.com",
                u"news:comp.infosystems.www.servers.unix",
                u"tel:+1-816-555-1212",
                u"telnet://192.0.2.16:80/",
                u"urn:oasis:names:specification:docbook:dtd:xml:4.1.2" ]
            for uri in invariant:
                self.assertEqual(uri, iri2uri(uri))
            
        def test_iri(self):
            """ Test that the right type of escaping is done for each part of the URI."""
            self.assertEqual("http://xn--o3h.com/%E2%98%84", iri2uri(u"http://\N{COMET}.com/\N{COMET}"))
            self.assertEqual("http://bitworking.org/?fred=%E2%98%84", iri2uri(u"http://bitworking.org/?fred=\N{COMET}"))
            self.assertEqual("http://bitworking.org/#%E2%98%84", iri2uri(u"http://bitworking.org/#\N{COMET}"))
            self.assertEqual("#%E2%98%84", iri2uri(u"#\N{COMET}"))
            self.assertEqual("/fred?bar=%E2%98%9A#%E2%98%84", iri2uri(u"/fred?bar=\N{BLACK LEFT POINTING INDEX}#\N{COMET}"))
            self.assertEqual("/fred?bar=%E2%98%9A#%E2%98%84", iri2uri(iri2uri(u"/fred?bar=\N{BLACK LEFT POINTING INDEX}#\N{COMET}")))
            self.assertNotEqual("/fred?bar=%E2%98%9A#%E2%98%84", iri2uri(u"/fred?bar=\N{BLACK LEFT POINTING INDEX}#\N{COMET}".encode('utf-8')))

    unittest.main()