class NamePrep:
""" Implements preparation of internationalized domain names.
This class implements preparing internationalized domain names using the
rules defined in RFC 3491, section 4 (Conversion operations).
We do not perform step 4 since we deal with unicode representations of
domain names and do not convert from or to ASCII representations using
punycode encoding. When such a conversion is needed, the C{idna} standard
library provides the C{ToUnicode()} and C{ToASCII()} functions. Note that
C{idna} itself assumes UseSTD3ASCIIRules to be false.
The following steps are performed by C{prepare()}:
- Split the domain name in labels at the dots (RFC 3490, 3.1)
- Apply nameprep proper on each label (RFC 3491)
- Enforce the restrictions on ASCII characters in host names by
assuming STD3ASCIIRules to be true. (STD 3)
- Rejoin the labels using the label separator U+002E (full stop).
"""
# Prohibited characters.
prohibiteds = [
unichr(n)
for n in chain(range(0x00, 0x2c + 1), range(0x2e, 0x2f + 1),
range(0x3a, 0x40 + 1), range(0x5b, 0x60 +
1), range(0x7b, 0x7f + 1))
]
def prepare(self, string):
result = []
labels = idna.dots.split(string)
if labels and len(labels[-1]) == 0:
trailing_dot = u'.'
del labels[-1]
else:
trailing_dot = u''
for label in labels:
result.append(self.nameprep(label))
return u".".join(result) + trailing_dot
def check_prohibiteds(self, string):
for c in string:
if c in self.prohibiteds:
raise UnicodeError("Invalid character %s" % repr(c))
def nameprep(self, label):
label = idna.nameprep(label)
self.check_prohibiteds(label)
if label[0] == u'-':
raise UnicodeError("Invalid leading hyphen-minus")
if label[-1] == u'-':
raise UnicodeError("Invalid trailing hyphen-minus")
return label
ESCAPE_ASCII = re.compile(r'([\\"]|[^\ -~])')
HAS_UTF8 = re.compile(r'[\x80-\xff]')
ESCAPE_DCT = {
'\\': '\\\\',
'"': '\\"',
'\b': '\\b',
'\f': '\\f',
'\n': '\\n',
'\r': '\\r',
'\t': '\\t',
}
for i in range(0x20):
#ESCAPE_DCT.setdefault(chr(i), '\\u{0:04x}'.format(i))
ESCAPE_DCT.setdefault(chr(i), '\\u%04x' % (i,))
for i in [0x2028, 0x2029]:
ESCAPE_DCT.setdefault(unichr(i), '\\u%04x' % (i,))
FLOAT_REPR = repr
def encode_basestring(s, _PY3=PY3, _q=u('"')):
"""Return a JSON representation of a Python string
"""
if _PY3:
if isinstance(s, binary_type):
s = s.decode('utf-8')
else:
if isinstance(s, str) and HAS_UTF8.search(s) is not None:
s = s.decode('utf-8')
def replace(match):
return ESCAPE_DCT[match.group(0)]
def py_scanstring(s, end, encoding=None, strict=True,
_b=BACKSLASH, _m=STRINGCHUNK.match, _join=u('').join,
_PY3=PY3, _maxunicode=sys.maxunicode):
"""Scan the string s for a JSON string. End is the index of the
character in s after the quote that started the JSON string.
Unescapes all valid JSON string escape sequences and raises ValueError
on attempt to decode an invalid string. If strict is False then literal
control characters are allowed in the string.
Returns a tuple of the decoded string and the index of the character in s
after the end quote."""
if encoding is None:
encoding = DEFAULT_ENCODING
chunks = []
_append = chunks.append
begin = end - 1
while 1:
chunk = _m(s, end)
if chunk is None:
raise JSONDecodeError(
"Unterminated string starting at", s, begin)
end = chunk.end()
content, terminator = chunk.groups()
# Content is contains zero or more unescaped string characters
if content:
if not _PY3 and not isinstance(content, text_type):
content = text_type(content, encoding)
_append(content)
# Terminator is the end of string, a literal control character,
# or a backslash denoting that an escape sequence follows
if terminator == '"':
break
elif terminator != '\\':
if strict:
msg = "Invalid control character %r at"
raise JSONDecodeError(msg, s, end)
else:
_append(terminator)
continue
try:
esc = s[end]
except IndexError:
raise JSONDecodeError(
"Unterminated string starting at", s, begin)
# If not a unicode escape sequence, must be in the lookup table
if esc != 'u':
try:
char = _b[esc]
except KeyError:
msg = "Invalid \\X escape sequence %r"
raise JSONDecodeError(msg, s, end)
end += 1
else:
# Unicode escape sequence
msg = "Invalid \\uXXXX escape sequence"
esc = s[end + 1:end + 5]
escX = esc[1:2]
if len(esc) != 4 or escX == 'x' or escX == 'X':
raise JSONDecodeError(msg, s, end - 1)
try:
uni = int(esc, 16)
except ValueError:
raise JSONDecodeError(msg, s, end - 1)
end += 5
# Check for surrogate pair on UCS-4 systems
# Note that this will join high/low surrogate pairs
# but will also pass unpaired surrogates through
if (_maxunicode > 65535 and
uni & 0xfc00 == 0xd800 and
s[end:end + 2] == '\\u'):
esc2 = s[end + 2:end + 6]
escX = esc2[1:2]
if len(esc2) == 4 and not (escX == 'x' or escX == 'X'):
try:
uni2 = int(esc2, 16)
except ValueError:
raise JSONDecodeError(msg, s, end)
if uni2 & 0xfc00 == 0xdc00:
uni = 0x10000 + (((uni - 0xd800) << 10) |
(uni2 - 0xdc00))
end += 6
char = unichr(uni)
# Append the unescaped character
_append(char)
return _join(chunks), end
def py_scanstring(s,
end,
encoding=None,
strict=True,
_b=BACKSLASH,
_m=STRINGCHUNK.match,
_join=u('').join,
_PY3=PY3,
_maxunicode=sys.maxunicode):
"""Scan the string s for a JSON string. End is the index of the
character in s after the quote that started the JSON string.
Unescapes all valid JSON string escape sequences and raises ValueError
on attempt to decode an invalid string. If strict is False then literal
control characters are allowed in the string.
Returns a tuple of the decoded string and the index of the character in s
after the end quote."""
if encoding is None:
encoding = DEFAULT_ENCODING
chunks = []
_append = chunks.append
begin = end - 1
while 1:
chunk = _m(s, end)
if chunk is None:
raise JSONDecodeError("Unterminated string starting at", s, begin)
end = chunk.end()
content, terminator = chunk.groups()
# Content is contains zero or more unescaped string characters
if content:
if not _PY3 and not isinstance(content, text_type):
content = text_type(content, encoding)
_append(content)
# Terminator is the end of string, a literal control character,
# or a backslash denoting that an escape sequence follows
if terminator == '"':
break
elif terminator != '\\':
if strict:
msg = "Invalid control character %r at"
raise JSONDecodeError(msg, s, end)
else:
_append(terminator)
continue
try:
esc = s[end]
except IndexError:
raise JSONDecodeError("Unterminated string starting at", s, begin)
# If not a unicode escape sequence, must be in the lookup table
if esc != 'u':
try:
char = _b[esc]
except KeyError:
msg = "Invalid \\X escape sequence %r"
raise JSONDecodeError(msg, s, end)
end += 1
else:
# Unicode escape sequence
msg = "Invalid \\uXXXX escape sequence"
esc = s[end + 1:end + 5]
escX = esc[1:2]
if len(esc) != 4 or escX == 'x' or escX == 'X':
raise JSONDecodeError(msg, s, end - 1)
try:
uni = int(esc, 16)
except ValueError:
raise JSONDecodeError(msg, s, end - 1)
end += 5
# Check for surrogate pair on UCS-4 systems
# Note that this will join high/low surrogate pairs
# but will also pass unpaired surrogates through
if (_maxunicode > 65535 and uni & 0xfc00 == 0xd800
and s[end:end + 2] == '\\u'):
esc2 = s[end + 2:end + 6]
escX = esc2[1:2]
if len(esc2) == 4 and not (escX == 'x' or escX == 'X'):
try:
uni2 = int(esc2, 16)
except ValueError:
raise JSONDecodeError(msg, s, end)
if uni2 & 0xfc00 == 0xdc00:
uni = 0x10000 + (((uni - 0xd800) << 10) |
(uni2 - 0xdc00))
end += 6
char = unichr(uni)
# Append the unescaped character
_append(char)
return _join(chunks), end
ESCAPE_ASCII = re.compile(r'([\\"]|[^\ -~])')
HAS_UTF8 = re.compile(r'[\x80-\xff]')
ESCAPE_DCT = {
'\\': '\\\\',
'"': '\\"',
'\b': '\\b',
'\f': '\\f',
'\n': '\\n',
'\r': '\\r',
'\t': '\\t',
}
for i in range(0x20):
#ESCAPE_DCT.setdefault(chr(i), '\\u{0:04x}'.format(i))
ESCAPE_DCT.setdefault(chr(i), '\\u%04x' % (i, ))
for i in [0x2028, 0x2029]:
ESCAPE_DCT.setdefault(unichr(i), '\\u%04x' % (i, ))
FLOAT_REPR = repr
def encode_basestring(s, _PY3=PY3, _q=u('"')):
"""Return a JSON representation of a Python string
"""
if _PY3:
if isinstance(s, binary_type):
s = s.decode('utf-8')
else:
if isinstance(s, str) and HAS_UTF8.search(s) is not None:
s = s.decode('utf-8')
