straw/httplib2/iri2uri.py

   1 """
   2 iri2uri
   3
   4 Converts an IRI to a URI.
   5
   6 """
   7 __author__ = "Joe Gregorio (joe@bitworking.org)"
   8 __copyright__ = "Copyright 2006, Joe Gregorio"
   9 __contributors__ = []
  10 __version__ = "1.0.0"
  11 __license__ = "MIT"
  12 __history__ = """
  13 """
  14
  15 import urlparse
  16
  17
  18 # Convert an IRI to a URI following the rules in RFC 3987
  19 #
  20 # The characters we need to enocde and escape are defined in the spec:
  21 #
  22 # iprivate =  %xE000-F8FF / %xF0000-FFFFD / %x100000-10FFFD
  23 # ucschar = %xA0-D7FF / %xF900-FDCF / %xFDF0-FFEF
  24 #         / %x10000-1FFFD / %x20000-2FFFD / %x30000-3FFFD
  25 #         / %x40000-4FFFD / %x50000-5FFFD / %x60000-6FFFD
  26 #         / %x70000-7FFFD / %x80000-8FFFD / %x90000-9FFFD
  27 #         / %xA0000-AFFFD / %xB0000-BFFFD / %xC0000-CFFFD
  28 #         / %xD0000-DFFFD / %xE1000-EFFFD
  29
  30 escape_range = [
  31    (0xA0, 0xD7FF ),
  32    (0xE000, 0xF8FF ),
  33    (0xF900, 0xFDCF ),
  34    (0xFDF0, 0xFFEF),
  35    (0x10000, 0x1FFFD ),
  36    (0x20000, 0x2FFFD ),
  37    (0x30000, 0x3FFFD),
  38    (0x40000, 0x4FFFD ),
  39    (0x50000, 0x5FFFD ),
  40    (0x60000, 0x6FFFD),
  41    (0x70000, 0x7FFFD ),
  42    (0x80000, 0x8FFFD ),
  43    (0x90000, 0x9FFFD),
  44    (0xA0000, 0xAFFFD ),
  45    (0xB0000, 0xBFFFD ),
  46    (0xC0000, 0xCFFFD),
  47    (0xD0000, 0xDFFFD ),
  48    (0xE1000, 0xEFFFD),
  49    (0xF0000, 0xFFFFD ),
  50    (0x100000, 0x10FFFD)
  51 ]
  52
  53 def encode(c):
  54     retval = c
  55     i = ord(c)
  56     for low, high in escape_range:
  57         if i < low:
  58             break
  59         if i >= low and i <= high:
  60             retval = "".join(["%%%2X" % ord(o) for o in c.encode('utf-8')])
  61             break
  62     return retval
  63
  64
  65 def iri2uri(uri):
  66     """Convert an IRI to a URI. Note that IRIs must be
  67     passed in a unicode strings. That is, do not utf-8 encode
  68     the IRI before passing it into the function."""
  69     if isinstance(uri ,unicode):
  70         (scheme, authority, path, query, fragment) = urlparse.urlsplit(uri)
  71         authority = authority.encode('idna')
  72         # For each character in 'ucschar' or 'iprivate'
  73         #  1. encode as utf-8
  74         #  2. then %-encode each octet of that utf-8
  75         uri = urlparse.urlunsplit((scheme, authority, path, query, fragment))
  76         uri = "".join([encode(c) for c in uri])
  77     return uri
  78
  79 if __name__ == "__main__":
  80     import unittest
  81
  82     class Test(unittest.TestCase):
  83
  84         def test_uris(self):
  85             """Test that URIs are invariant under the transformation."""
  86             invariant = [
  87                 u"ftp://ftp.is.co.za/rfc/rfc1808.txt",
  88                 u"http://www.ietf.org/rfc/rfc2396.txt",
  89                 u"ldap://[2001:db8::7]/c=GB?objectClass?one",
  90                 u"mailto:John.Doe@example.com",
  91                 u"news:comp.infosystems.www.servers.unix",
  92                 u"tel:+1-816-555-1212",
  93                 u"telnet://192.0.2.16:80/",
  94                 u"urn:oasis:names:specification:docbook:dtd:xml:4.1.2" ]
  95             for uri in invariant:
  96                 self.assertEqual(uri, iri2uri(uri))
  97
  98         def test_iri(self):
  99             """ Test that the right type of escaping is done for each part of the URI."""
 100             self.assertEqual("http://xn--o3h.com/%E2%98%84", iri2uri(u"http://\N{COMET}.com/\N{COMET}"))
 101             self.assertEqual("http://bitworking.org/?fred=%E2%98%84", iri2uri(u"http://bitworking.org/?fred=\N{COMET}"))
 102             self.assertEqual("http://bitworking.org/#%E2%98%84", iri2uri(u"http://bitworking.org/#\N{COMET}"))
 103             self.assertEqual("#%E2%98%84", iri2uri(u"#\N{COMET}"))
 104             self.assertEqual("/fred?bar=%E2%98%9A#%E2%98%84", iri2uri(u"/fred?bar=\N{BLACK LEFT POINTING INDEX}#\N{COMET}"))
 105             self.assertEqual("/fred?bar=%E2%98%9A#%E2%98%84", iri2uri(iri2uri(u"/fred?bar=\N{BLACK LEFT POINTING INDEX}#\N{COMET}")))
 106             self.assertNotEqual("/fred?bar=%E2%98%9A#%E2%98%84", iri2uri(u"/fred?bar=\N{BLACK LEFT POINTING INDEX}#\N{COMET}".encode('utf-8')))
 107
 108     unittest.main()
 109
 110